You are viewing a plain text version of this content. The canonical link for it is here.
Posted to commits@accumulo.apache.org by kt...@apache.org on 2015/09/21 15:51:28 UTC

[3/7] accumulo git commit: ACCUMULO-3913 Added per table sampling

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/core/src/main/java/org/apache/accumulo/core/util/LocalityGroupUtil.java
----------------------------------------------------------------------
diff --git a/core/src/main/java/org/apache/accumulo/core/util/LocalityGroupUtil.java b/core/src/main/java/org/apache/accumulo/core/util/LocalityGroupUtil.java
index a4936cf..07757a6 100644
--- a/core/src/main/java/org/apache/accumulo/core/util/LocalityGroupUtil.java
+++ b/core/src/main/java/org/apache/accumulo/core/util/LocalityGroupUtil.java
@@ -186,11 +186,11 @@ public class LocalityGroupUtil {
     return ecf;
   }
 
-  private static class PartitionedMutation extends Mutation {
+  public static class PartitionedMutation extends Mutation {
     private byte[] row;
     private List<ColumnUpdate> updates;
 
-    PartitionedMutation(byte[] row, List<ColumnUpdate> updates) {
+    public PartitionedMutation(byte[] row, List<ColumnUpdate> updates) {
       this.row = row;
       this.updates = updates;
     }

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/core/src/main/thrift/tabletserver.thrift
----------------------------------------------------------------------
diff --git a/core/src/main/thrift/tabletserver.thrift b/core/src/main/thrift/tabletserver.thrift
index 051daee..27b72f2 100644
--- a/core/src/main/thrift/tabletserver.thrift
+++ b/core/src/main/thrift/tabletserver.thrift
@@ -31,6 +31,10 @@ exception TooManyFilesException {
   1:data.TKeyExtent extent
 }
 
+exception TSampleNotPresentException {
+  1:data.TKeyExtent extent
+}
+
 exception NoSuchScanIDException {
 }
 
@@ -136,6 +140,11 @@ struct IteratorConfig {
    1:list<TIteratorSetting> iterators;
 }
 
+struct TSamplerConfiguration {
+   1:string className
+   2:map<string, string> options
+}
+
 service TabletClientService extends client.ClientService {
   // scan a range of keys
   data.InitialScan startScan(11:trace.TInfo tinfo,
@@ -150,9 +159,10 @@ service TabletClientService extends client.ClientService {
                              9:bool waitForWrites,
                              10:bool isolated,
                              12:i64 readaheadThreshold,
-                             13:i64 batchTimeOut)  throws (1:client.ThriftSecurityException sec, 2:NotServingTabletException nste, 3:TooManyFilesException tmfe),
+                             13:TSamplerConfiguration samplerConfig,
+                             14:i64 batchTimeOut)  throws (1:client.ThriftSecurityException sec, 2:NotServingTabletException nste, 3:TooManyFilesException tmfe, 4:TSampleNotPresentException tsnpe),
                              
-  data.ScanResult continueScan(2:trace.TInfo tinfo, 1:data.ScanID scanID)  throws (1:NoSuchScanIDException nssi, 2:NotServingTabletException nste, 3:TooManyFilesException tmfe),
+  data.ScanResult continueScan(2:trace.TInfo tinfo, 1:data.ScanID scanID)  throws (1:NoSuchScanIDException nssi, 2:NotServingTabletException nste, 3:TooManyFilesException tmfe, 4:TSampleNotPresentException tsnpe),
   oneway void closeScan(2:trace.TInfo tinfo, 1:data.ScanID scanID),
 
   // scan over a series of ranges
@@ -164,8 +174,9 @@ service TabletClientService extends client.ClientService {
                                   5:map<string, map<string, string>> ssio,
                                   6:list<binary> authorizations,
                                   7:bool waitForWrites,
-                                  9:i64 batchTimeOut)  throws (1:client.ThriftSecurityException sec),
-  data.MultiScanResult continueMultiScan(2:trace.TInfo tinfo, 1:data.ScanID scanID) throws (1:NoSuchScanIDException nssi),
+                                  9:TSamplerConfiguration samplerConfig,
+                                  10:i64 batchTimeOut)  throws (1:client.ThriftSecurityException sec, 2:TSampleNotPresentException tsnpe),
+  data.MultiScanResult continueMultiScan(2:trace.TInfo tinfo, 1:data.ScanID scanID) throws (1:NoSuchScanIDException nssi, 2:TSampleNotPresentException tsnpe),
   void closeMultiScan(2:trace.TInfo tinfo, 1:data.ScanID scanID) throws (1:NoSuchScanIDException nssi),
   
   //the following calls support a batch update to multiple tablets on a tablet server

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/core/src/test/java/org/apache/accumulo/core/client/impl/TableOperationsHelperTest.java
----------------------------------------------------------------------
diff --git a/core/src/test/java/org/apache/accumulo/core/client/impl/TableOperationsHelperTest.java b/core/src/test/java/org/apache/accumulo/core/client/impl/TableOperationsHelperTest.java
index 7a56d1d..7bf9eb1 100644
--- a/core/src/test/java/org/apache/accumulo/core/client/impl/TableOperationsHelperTest.java
+++ b/core/src/test/java/org/apache/accumulo/core/client/impl/TableOperationsHelperTest.java
@@ -36,6 +36,7 @@ import org.apache.accumulo.core.client.TableNotFoundException;
 import org.apache.accumulo.core.client.admin.CompactionConfig;
 import org.apache.accumulo.core.client.admin.DiskUsage;
 import org.apache.accumulo.core.client.admin.NewTableConfiguration;
+import org.apache.accumulo.core.client.admin.SamplerConfiguration;
 import org.apache.accumulo.core.client.admin.TimeType;
 import org.apache.accumulo.core.data.Range;
 import org.apache.accumulo.core.iterators.IteratorUtil.IteratorScope;
@@ -226,6 +227,22 @@ public class TableOperationsHelperTest {
         TableNotFoundException {
       return false;
     }
+
+    @Override
+    public void setSamplerConfiguration(String tableName, SamplerConfiguration samplerConfiguration) throws TableNotFoundException, AccumuloException,
+        AccumuloSecurityException {
+      throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public void clearSamplerConfiguration(String tableName) throws TableNotFoundException, AccumuloException, AccumuloSecurityException {
+      throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public SamplerConfiguration getSamplerConfiguration(String tableName) throws TableNotFoundException, AccumuloException, AccumuloSecurityException {
+      throw new UnsupportedOperationException();
+    }
   }
 
   protected TableOperationsHelper getHelper() {

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/core/src/test/java/org/apache/accumulo/core/client/mapred/AccumuloFileOutputFormatTest.java
----------------------------------------------------------------------
diff --git a/core/src/test/java/org/apache/accumulo/core/client/mapred/AccumuloFileOutputFormatTest.java b/core/src/test/java/org/apache/accumulo/core/client/mapred/AccumuloFileOutputFormatTest.java
index bcf8a24..d88453e 100644
--- a/core/src/test/java/org/apache/accumulo/core/client/mapred/AccumuloFileOutputFormatTest.java
+++ b/core/src/test/java/org/apache/accumulo/core/client/mapred/AccumuloFileOutputFormatTest.java
@@ -20,9 +20,12 @@ import static org.junit.Assert.assertEquals;
 
 import java.io.IOException;
 
+import org.apache.accumulo.core.client.admin.SamplerConfiguration;
 import org.apache.accumulo.core.client.mapreduce.lib.impl.FileOutputConfigurator;
 import org.apache.accumulo.core.conf.AccumuloConfiguration;
 import org.apache.accumulo.core.conf.Property;
+import org.apache.accumulo.core.sample.RowSampler;
+import org.apache.accumulo.core.sample.impl.SamplerConfigurationImpl;
 import org.apache.hadoop.mapred.JobConf;
 import org.junit.Test;
 
@@ -36,6 +39,9 @@ public class AccumuloFileOutputFormatTest {
     long c = 50l;
     long d = 10l;
     String e = "snappy";
+    SamplerConfiguration samplerConfig = new SamplerConfiguration(RowSampler.class.getName());
+    samplerConfig.addOption("hasher", "murmur3_32");
+    samplerConfig.addOption("modulus", "109");
 
     JobConf job = new JobConf();
     AccumuloFileOutputFormat.setReplication(job, a);
@@ -43,6 +49,7 @@ public class AccumuloFileOutputFormatTest {
     AccumuloFileOutputFormat.setDataBlockSize(job, c);
     AccumuloFileOutputFormat.setIndexBlockSize(job, d);
     AccumuloFileOutputFormat.setCompressionType(job, e);
+    AccumuloFileOutputFormat.setSampler(job, samplerConfig);
 
     AccumuloConfiguration acuconf = FileOutputConfigurator.getAccumuloConfiguration(AccumuloFileOutputFormat.class, job);
 
@@ -51,12 +58,16 @@ public class AccumuloFileOutputFormatTest {
     assertEquals(50l, acuconf.getMemoryInBytes(Property.TABLE_FILE_COMPRESSED_BLOCK_SIZE));
     assertEquals(10l, acuconf.getMemoryInBytes(Property.TABLE_FILE_COMPRESSED_BLOCK_SIZE_INDEX));
     assertEquals("snappy", acuconf.get(Property.TABLE_FILE_COMPRESSION_TYPE));
+    assertEquals(new SamplerConfigurationImpl(samplerConfig), SamplerConfigurationImpl.newSamplerConfig(acuconf));
 
     a = 17;
     b = 1300l;
     c = 150l;
     d = 110l;
     e = "lzo";
+    samplerConfig = new SamplerConfiguration(RowSampler.class.getName());
+    samplerConfig.addOption("hasher", "md5");
+    samplerConfig.addOption("modulus", "100003");
 
     job = new JobConf();
     AccumuloFileOutputFormat.setReplication(job, a);
@@ -64,6 +75,7 @@ public class AccumuloFileOutputFormatTest {
     AccumuloFileOutputFormat.setDataBlockSize(job, c);
     AccumuloFileOutputFormat.setIndexBlockSize(job, d);
     AccumuloFileOutputFormat.setCompressionType(job, e);
+    AccumuloFileOutputFormat.setSampler(job, samplerConfig);
 
     acuconf = FileOutputConfigurator.getAccumuloConfiguration(AccumuloFileOutputFormat.class, job);
 
@@ -72,6 +84,6 @@ public class AccumuloFileOutputFormatTest {
     assertEquals(150l, acuconf.getMemoryInBytes(Property.TABLE_FILE_COMPRESSED_BLOCK_SIZE));
     assertEquals(110l, acuconf.getMemoryInBytes(Property.TABLE_FILE_COMPRESSED_BLOCK_SIZE_INDEX));
     assertEquals("lzo", acuconf.get(Property.TABLE_FILE_COMPRESSION_TYPE));
-
+    assertEquals(new SamplerConfigurationImpl(samplerConfig), SamplerConfigurationImpl.newSamplerConfig(acuconf));
   }
 }

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/core/src/test/java/org/apache/accumulo/core/client/mapreduce/AccumuloFileOutputFormatTest.java
----------------------------------------------------------------------
diff --git a/core/src/test/java/org/apache/accumulo/core/client/mapreduce/AccumuloFileOutputFormatTest.java b/core/src/test/java/org/apache/accumulo/core/client/mapreduce/AccumuloFileOutputFormatTest.java
index 3923566..cf0c8d6 100644
--- a/core/src/test/java/org/apache/accumulo/core/client/mapreduce/AccumuloFileOutputFormatTest.java
+++ b/core/src/test/java/org/apache/accumulo/core/client/mapreduce/AccumuloFileOutputFormatTest.java
@@ -20,9 +20,12 @@ import static org.junit.Assert.assertEquals;
 
 import java.io.IOException;
 
+import org.apache.accumulo.core.client.admin.SamplerConfiguration;
 import org.apache.accumulo.core.client.mapreduce.lib.impl.FileOutputConfigurator;
 import org.apache.accumulo.core.conf.AccumuloConfiguration;
 import org.apache.accumulo.core.conf.Property;
+import org.apache.accumulo.core.sample.RowSampler;
+import org.apache.accumulo.core.sample.impl.SamplerConfigurationImpl;
 import org.apache.hadoop.mapreduce.Job;
 import org.junit.Test;
 
@@ -36,6 +39,9 @@ public class AccumuloFileOutputFormatTest {
     long c = 50l;
     long d = 10l;
     String e = "snappy";
+    SamplerConfiguration samplerConfig = new SamplerConfiguration(RowSampler.class.getName());
+    samplerConfig.addOption("hasher", "murmur3_32");
+    samplerConfig.addOption("modulus", "109");
 
     Job job1 = Job.getInstance();
     AccumuloFileOutputFormat.setReplication(job1, a);
@@ -43,6 +49,7 @@ public class AccumuloFileOutputFormatTest {
     AccumuloFileOutputFormat.setDataBlockSize(job1, c);
     AccumuloFileOutputFormat.setIndexBlockSize(job1, d);
     AccumuloFileOutputFormat.setCompressionType(job1, e);
+    AccumuloFileOutputFormat.setSampler(job1, samplerConfig);
 
     AccumuloConfiguration acuconf = FileOutputConfigurator.getAccumuloConfiguration(AccumuloFileOutputFormat.class, job1.getConfiguration());
 
@@ -51,12 +58,16 @@ public class AccumuloFileOutputFormatTest {
     assertEquals(50l, acuconf.getMemoryInBytes(Property.TABLE_FILE_COMPRESSED_BLOCK_SIZE));
     assertEquals(10l, acuconf.getMemoryInBytes(Property.TABLE_FILE_COMPRESSED_BLOCK_SIZE_INDEX));
     assertEquals("snappy", acuconf.get(Property.TABLE_FILE_COMPRESSION_TYPE));
+    assertEquals(new SamplerConfigurationImpl(samplerConfig), SamplerConfigurationImpl.newSamplerConfig(acuconf));
 
     a = 17;
     b = 1300l;
     c = 150l;
     d = 110l;
     e = "lzo";
+    samplerConfig = new SamplerConfiguration(RowSampler.class.getName());
+    samplerConfig.addOption("hasher", "md5");
+    samplerConfig.addOption("modulus", "100003");
 
     Job job2 = Job.getInstance();
     AccumuloFileOutputFormat.setReplication(job2, a);
@@ -64,6 +75,7 @@ public class AccumuloFileOutputFormatTest {
     AccumuloFileOutputFormat.setDataBlockSize(job2, c);
     AccumuloFileOutputFormat.setIndexBlockSize(job2, d);
     AccumuloFileOutputFormat.setCompressionType(job2, e);
+    AccumuloFileOutputFormat.setSampler(job2, samplerConfig);
 
     acuconf = FileOutputConfigurator.getAccumuloConfiguration(AccumuloFileOutputFormat.class, job2.getConfiguration());
 
@@ -72,6 +84,7 @@ public class AccumuloFileOutputFormatTest {
     assertEquals(150l, acuconf.getMemoryInBytes(Property.TABLE_FILE_COMPRESSED_BLOCK_SIZE));
     assertEquals(110l, acuconf.getMemoryInBytes(Property.TABLE_FILE_COMPRESSED_BLOCK_SIZE_INDEX));
     assertEquals("lzo", acuconf.get(Property.TABLE_FILE_COMPRESSION_TYPE));
+    assertEquals(new SamplerConfigurationImpl(samplerConfig), SamplerConfigurationImpl.newSamplerConfig(acuconf));
 
   }
 }

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/core/src/test/java/org/apache/accumulo/core/file/rfile/MultiLevelIndexTest.java
----------------------------------------------------------------------
diff --git a/core/src/test/java/org/apache/accumulo/core/file/rfile/MultiLevelIndexTest.java b/core/src/test/java/org/apache/accumulo/core/file/rfile/MultiLevelIndexTest.java
index 6f89454..66978dd 100644
--- a/core/src/test/java/org/apache/accumulo/core/file/rfile/MultiLevelIndexTest.java
+++ b/core/src/test/java/org/apache/accumulo/core/file/rfile/MultiLevelIndexTest.java
@@ -21,7 +21,6 @@ import java.io.IOException;
 import java.util.Random;
 
 import junit.framework.TestCase;
-
 import org.apache.accumulo.core.conf.AccumuloConfiguration;
 import org.apache.accumulo.core.data.Key;
 import org.apache.accumulo.core.file.blockfile.ABlockWriter;
@@ -77,7 +76,7 @@ public class MultiLevelIndexTest extends TestCase {
     FSDataInputStream in = new FSDataInputStream(bais);
     CachableBlockFile.Reader _cbr = new CachableBlockFile.Reader(in, data.length, CachedConfiguration.getInstance(), aconf);
 
-    Reader reader = new Reader(_cbr, RFile.RINDEX_VER_7);
+    Reader reader = new Reader(_cbr, RFile.RINDEX_VER_8);
     BlockRead rootIn = _cbr.getMetaBlock("root");
     reader.readFields(rootIn);
     rootIn.close();

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/core/src/test/java/org/apache/accumulo/core/file/rfile/RFileTest.java
----------------------------------------------------------------------
diff --git a/core/src/test/java/org/apache/accumulo/core/file/rfile/RFileTest.java b/core/src/test/java/org/apache/accumulo/core/file/rfile/RFileTest.java
index 2e2b346..ab98f49 100644
--- a/core/src/test/java/org/apache/accumulo/core/file/rfile/RFileTest.java
+++ b/core/src/test/java/org/apache/accumulo/core/file/rfile/RFileTest.java
@@ -28,16 +28,21 @@ import java.io.File;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
+import java.util.AbstractMap;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
+import java.util.Comparator;
 import java.util.HashSet;
 import java.util.Iterator;
+import java.util.List;
 import java.util.Map.Entry;
 import java.util.Random;
 import java.util.Set;
 
 import org.apache.accumulo.core.Constants;
+import org.apache.accumulo.core.client.admin.SamplerConfiguration;
+import org.apache.accumulo.core.client.impl.BaseIteratorEnvironment;
 import org.apache.accumulo.core.conf.AccumuloConfiguration;
 import org.apache.accumulo.core.conf.ConfigurationCopy;
 import org.apache.accumulo.core.conf.Property;
@@ -57,6 +62,10 @@ import org.apache.accumulo.core.iterators.system.ColumnFamilySkippingIterator;
 import org.apache.accumulo.core.metadata.MetadataTable;
 import org.apache.accumulo.core.metadata.schema.MetadataSchema;
 import org.apache.accumulo.core.metadata.schema.MetadataSchema.TabletsSection;
+import org.apache.accumulo.core.sample.RowSampler;
+import org.apache.accumulo.core.sample.Sampler;
+import org.apache.accumulo.core.sample.impl.SamplerConfigurationImpl;
+import org.apache.accumulo.core.sample.impl.SamplerFactory;
 import org.apache.accumulo.core.security.crypto.CryptoTest;
 import org.apache.accumulo.core.util.CachedConfiguration;
 import org.apache.hadoop.conf.Configuration;
@@ -68,14 +77,37 @@ import org.apache.hadoop.fs.Seekable;
 import org.apache.hadoop.io.Text;
 import org.apache.log4j.Level;
 import org.apache.log4j.Logger;
+import org.junit.Assert;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.TemporaryFolder;
 
+import com.google.common.hash.HashCode;
+import com.google.common.hash.Hasher;
+import com.google.common.hash.Hashing;
 import com.google.common.primitives.Bytes;
 
 public class RFileTest {
 
+  public static class SampleIE extends BaseIteratorEnvironment {
+
+    private SamplerConfiguration samplerConfig;
+
+    SampleIE(SamplerConfiguration config) {
+      this.samplerConfig = config;
+    }
+
+    @Override
+    public boolean isSamplingEnabled() {
+      return samplerConfig != null;
+    }
+
+    @Override
+    public SamplerConfiguration getSamplerConfiguration() {
+      return samplerConfig;
+    }
+  }
+
   private static final Collection<ByteSequence> EMPTY_COL_FAMS = new ArrayList<ByteSequence>();
 
   @Rule
@@ -193,7 +225,15 @@ public class RFileTest {
       baos = new ByteArrayOutputStream();
       dos = new FSDataOutputStream(baos, new FileSystem.Statistics("a"));
       CachableBlockFile.Writer _cbw = new CachableBlockFile.Writer(dos, "gz", conf, accumuloConfiguration);
-      writer = new RFile.Writer(_cbw, blockSize, 1000);
+
+      SamplerConfigurationImpl samplerConfig = SamplerConfigurationImpl.newSamplerConfig(accumuloConfiguration);
+      Sampler sampler = null;
+
+      if (samplerConfig != null) {
+        sampler = SamplerFactory.newSampler(samplerConfig, accumuloConfiguration);
+      }
+
+      writer = new RFile.Writer(_cbw, blockSize, 1000, samplerConfig, sampler);
 
       if (startDLG)
         writer.startDefaultLocalityGroup();
@@ -221,7 +261,6 @@ public class RFileTest {
     }
 
     public void openReader(boolean cfsi) throws IOException {
-
       int fileLength = 0;
       byte[] data = null;
       data = baos.toByteArray();
@@ -1206,7 +1245,6 @@ public class RFileTest {
   @Test
   public void test14() throws IOException {
     // test starting locality group after default locality group was started
-
     TestRFile trf = new TestRFile(conf);
 
     trf.openWriter(false);
@@ -1558,6 +1596,7 @@ public class RFileTest {
     runVersionTest(3);
     runVersionTest(4);
     runVersionTest(6);
+    runVersionTest(7);
   }
 
   private void runVersionTest(int version) throws IOException {
@@ -1762,6 +1801,294 @@ public class RFileTest {
     conf = null;
   }
 
+  private Key nk(int r, int c) {
+    String row = String.format("r%06d", r);
+    switch (c) {
+      case 0:
+        return new Key(row, "user", "addr");
+      case 1:
+        return new Key(row, "user", "name");
+      default:
+        throw new IllegalArgumentException();
+    }
+  }
+
+  private Value nv(int r, int c) {
+    switch (c) {
+      case 0:
+        return new Value(("123" + r + " west st").getBytes());
+      case 1:
+        return new Value(("bob" + r).getBytes());
+      default:
+        throw new IllegalArgumentException();
+    }
+  }
+
+  private static void hash(Hasher hasher, Key key, Value val) {
+    hasher.putBytes(key.getRowData().toArray());
+    hasher.putBytes(key.getColumnFamilyData().toArray());
+    hasher.putBytes(key.getColumnQualifierData().toArray());
+    hasher.putBytes(key.getColumnVisibilityData().toArray());
+    hasher.putLong(key.getTimestamp());
+    hasher.putBoolean(key.isDeleted());
+    hasher.putBytes(val.get());
+  }
+
+  private static void add(TestRFile trf, Key key, Value val, Hasher dataHasher, List<Entry<Key,Value>> sample, Sampler sampler) throws IOException {
+    if (sampler.accept(key)) {
+      sample.add(new AbstractMap.SimpleImmutableEntry<Key,Value>(key, val));
+    }
+
+    hash(dataHasher, key, val);
+
+    trf.writer.append(key, val);
+  }
+
+  private List<Entry<Key,Value>> toList(SortedKeyValueIterator<Key,Value> sample) throws IOException {
+    ArrayList<Entry<Key,Value>> ret = new ArrayList<>();
+
+    while (sample.hasTop()) {
+      ret.add(new AbstractMap.SimpleImmutableEntry<Key,Value>(new Key(sample.getTopKey()), new Value(sample.getTopValue())));
+      sample.next();
+    }
+
+    return ret;
+  }
+
+  private void checkSample(SortedKeyValueIterator<Key,Value> sample, List<Entry<Key,Value>> sampleData) throws IOException {
+    checkSample(sample, sampleData, EMPTY_COL_FAMS, false);
+  }
+
+  private void checkSample(SortedKeyValueIterator<Key,Value> sample, List<Entry<Key,Value>> sampleData, Collection<ByteSequence> columnFamilies,
+      boolean inclusive) throws IOException {
+
+    sample.seek(new Range(), columnFamilies, inclusive);
+    Assert.assertEquals(sampleData, toList(sample));
+
+    Random rand = new Random();
+    long seed = rand.nextLong();
+    rand = new Random(seed);
+
+    // randomly seek sample iterator and verify
+    for (int i = 0; i < 33; i++) {
+      Key startKey = null;
+      boolean startInclusive = false;
+      int startIndex = 0;
+
+      Key endKey = null;
+      boolean endInclusive = false;
+      int endIndex = sampleData.size();
+
+      if (rand.nextBoolean()) {
+        startIndex = rand.nextInt(sampleData.size());
+        startKey = sampleData.get(startIndex).getKey();
+        startInclusive = rand.nextBoolean();
+        if (!startInclusive) {
+          startIndex++;
+        }
+      }
+
+      if (startIndex < endIndex && rand.nextBoolean()) {
+        endIndex -= rand.nextInt(endIndex - startIndex);
+        endKey = sampleData.get(endIndex - 1).getKey();
+        endInclusive = rand.nextBoolean();
+        if (!endInclusive) {
+          endIndex--;
+        }
+      } else if (startIndex == endIndex) {
+        endInclusive = rand.nextBoolean();
+      }
+
+      sample.seek(new Range(startKey, startInclusive, endKey, endInclusive), columnFamilies, inclusive);
+      Assert.assertEquals("seed: " + seed, sampleData.subList(startIndex, endIndex), toList(sample));
+    }
+  }
+
+  @Test
+  public void testSample() throws IOException {
+
+    int num = 10000;
+
+    for (int sampleBufferSize : new int[] {1 << 10, 1 << 20}) {
+      // force sample buffer to flush for smaller data
+      RFile.setSampleBufferSize(sampleBufferSize);
+
+      for (int modulus : new int[] {19, 103, 1019}) {
+        Hasher dataHasher = Hashing.md5().newHasher();
+        List<Entry<Key,Value>> sampleData = new ArrayList<Entry<Key,Value>>();
+
+        ConfigurationCopy sampleConf = new ConfigurationCopy(conf == null ? AccumuloConfiguration.getDefaultConfiguration() : conf);
+        sampleConf.set(Property.TABLE_SAMPLER, RowSampler.class.getName());
+        sampleConf.set(Property.TABLE_SAMPLER_OPTS + "hasher", "murmur3_32");
+        sampleConf.set(Property.TABLE_SAMPLER_OPTS + "modulus", modulus + "");
+
+        Sampler sampler = SamplerFactory.newSampler(SamplerConfigurationImpl.newSamplerConfig(sampleConf), sampleConf);
+
+        TestRFile trf = new TestRFile(sampleConf);
+
+        trf.openWriter();
+
+        for (int i = 0; i < num; i++) {
+          add(trf, nk(i, 0), nv(i, 0), dataHasher, sampleData, sampler);
+          add(trf, nk(i, 1), nv(i, 1), dataHasher, sampleData, sampler);
+        }
+
+        HashCode expectedDataHash = dataHasher.hash();
+
+        trf.closeWriter();
+
+        trf.openReader();
+
+        FileSKVIterator sample = trf.reader.getSample(SamplerConfigurationImpl.newSamplerConfig(sampleConf));
+
+        checkSample(sample, sampleData);
+
+        Assert.assertEquals(expectedDataHash, hash(trf.reader));
+
+        SampleIE ie = new SampleIE(SamplerConfigurationImpl.newSamplerConfig(sampleConf).toSamplerConfiguration());
+
+        for (int i = 0; i < 3; i++) {
+          // test opening and closing deep copies a few times.
+          trf.reader.closeDeepCopies();
+
+          sample = trf.reader.getSample(SamplerConfigurationImpl.newSamplerConfig(sampleConf));
+          SortedKeyValueIterator<Key,Value> sampleDC1 = sample.deepCopy(ie);
+          SortedKeyValueIterator<Key,Value> sampleDC2 = sample.deepCopy(ie);
+          SortedKeyValueIterator<Key,Value> sampleDC3 = trf.reader.deepCopy(ie);
+          SortedKeyValueIterator<Key,Value> allDC1 = sampleDC1.deepCopy(new SampleIE(null));
+          SortedKeyValueIterator<Key,Value> allDC2 = sample.deepCopy(new SampleIE(null));
+
+          Assert.assertEquals(expectedDataHash, hash(allDC1));
+          Assert.assertEquals(expectedDataHash, hash(allDC2));
+
+          checkSample(sample, sampleData);
+          checkSample(sampleDC1, sampleData);
+          checkSample(sampleDC2, sampleData);
+          checkSample(sampleDC3, sampleData);
+        }
+
+        trf.reader.closeDeepCopies();
+
+        trf.closeReader();
+      }
+    }
+  }
+
+  private HashCode hash(SortedKeyValueIterator<Key,Value> iter) throws IOException {
+    Hasher dataHasher = Hashing.md5().newHasher();
+    iter.seek(new Range(), EMPTY_COL_FAMS, false);
+    while (iter.hasTop()) {
+      hash(dataHasher, iter.getTopKey(), iter.getTopValue());
+      iter.next();
+    }
+
+    return dataHasher.hash();
+  }
+
+  @Test
+  public void testSampleLG() throws IOException {
+
+    int num = 5000;
+
+    for (int sampleBufferSize : new int[] {1 << 10, 1 << 20}) {
+      // force sample buffer to flush for smaller data
+      RFile.setSampleBufferSize(sampleBufferSize);
+
+      for (int modulus : new int[] {19, 103, 1019}) {
+        List<Entry<Key,Value>> sampleDataLG1 = new ArrayList<Entry<Key,Value>>();
+        List<Entry<Key,Value>> sampleDataLG2 = new ArrayList<Entry<Key,Value>>();
+
+        ConfigurationCopy sampleConf = new ConfigurationCopy(conf == null ? AccumuloConfiguration.getDefaultConfiguration() : conf);
+        sampleConf.set(Property.TABLE_SAMPLER, RowSampler.class.getName());
+        sampleConf.set(Property.TABLE_SAMPLER_OPTS + "hasher", "murmur3_32");
+        sampleConf.set(Property.TABLE_SAMPLER_OPTS + "modulus", modulus + "");
+
+        Sampler sampler = SamplerFactory.newSampler(SamplerConfigurationImpl.newSamplerConfig(sampleConf), sampleConf);
+
+        TestRFile trf = new TestRFile(sampleConf);
+
+        trf.openWriter(false, 1000);
+
+        trf.writer.startNewLocalityGroup("meta-lg", ncfs("metaA", "metaB"));
+        for (int r = 0; r < num; r++) {
+          String row = String.format("r%06d", r);
+          Key k1 = new Key(row, "metaA", "q9", 7);
+          Key k2 = new Key(row, "metaB", "q8", 7);
+          Key k3 = new Key(row, "metaB", "qA", 7);
+
+          Value v1 = new Value(("" + r).getBytes());
+          Value v2 = new Value(("" + r * 93).getBytes());
+          Value v3 = new Value(("" + r * 113).getBytes());
+
+          if (sampler.accept(k1)) {
+            sampleDataLG1.add(new AbstractMap.SimpleImmutableEntry<Key,Value>(k1, v1));
+            sampleDataLG1.add(new AbstractMap.SimpleImmutableEntry<Key,Value>(k2, v2));
+            sampleDataLG1.add(new AbstractMap.SimpleImmutableEntry<Key,Value>(k3, v3));
+          }
+
+          trf.writer.append(k1, v1);
+          trf.writer.append(k2, v2);
+          trf.writer.append(k3, v3);
+        }
+
+        trf.writer.startDefaultLocalityGroup();
+
+        for (int r = 0; r < num; r++) {
+          String row = String.format("r%06d", r);
+          Key k1 = new Key(row, "dataA", "q9", 7);
+
+          Value v1 = new Value(("" + r).getBytes());
+
+          if (sampler.accept(k1)) {
+            sampleDataLG2.add(new AbstractMap.SimpleImmutableEntry<Key,Value>(k1, v1));
+          }
+
+          trf.writer.append(k1, v1);
+        }
+
+        trf.closeWriter();
+
+        Assert.assertTrue(sampleDataLG1.size() > 0);
+        Assert.assertTrue(sampleDataLG2.size() > 0);
+
+        trf.openReader(false);
+        FileSKVIterator sample = trf.reader.getSample(SamplerConfigurationImpl.newSamplerConfig(sampleConf));
+
+        checkSample(sample, sampleDataLG1, ncfs("metaA", "metaB"), true);
+        checkSample(sample, sampleDataLG1, ncfs("metaA"), true);
+        checkSample(sample, sampleDataLG1, ncfs("metaB"), true);
+        checkSample(sample, sampleDataLG1, ncfs("dataA"), false);
+
+        checkSample(sample, sampleDataLG2, ncfs("metaA", "metaB"), false);
+        checkSample(sample, sampleDataLG2, ncfs("dataA"), true);
+
+        ArrayList<Entry<Key,Value>> allSampleData = new ArrayList<Entry<Key,Value>>();
+        allSampleData.addAll(sampleDataLG1);
+        allSampleData.addAll(sampleDataLG2);
+
+        Collections.sort(allSampleData, new Comparator<Entry<Key,Value>>() {
+          @Override
+          public int compare(Entry<Key,Value> o1, Entry<Key,Value> o2) {
+            return o1.getKey().compareTo(o2.getKey());
+          }
+        });
+
+        checkSample(sample, allSampleData, ncfs("dataA", "metaA"), true);
+        checkSample(sample, allSampleData, EMPTY_COL_FAMS, false);
+
+        trf.closeReader();
+      }
+    }
+  }
+
+  @Test
+  public void testEncSample() throws IOException {
+    conf = setAndGetAccumuloConfig(CryptoTest.CRYPTO_ON_CONF);
+    testSample();
+    testSampleLG();
+    conf = null;
+  }
+
   @Test
   public void testCryptoDoesntLeakSensitive() throws IOException {
     conf = setAndGetAccumuloConfig(CryptoTest.CRYPTO_ON_CONF);

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/core/src/test/java/org/apache/accumulo/core/iterators/DefaultIteratorEnvironment.java
----------------------------------------------------------------------
diff --git a/core/src/test/java/org/apache/accumulo/core/iterators/DefaultIteratorEnvironment.java b/core/src/test/java/org/apache/accumulo/core/iterators/DefaultIteratorEnvironment.java
index 316823c..3c68196 100644
--- a/core/src/test/java/org/apache/accumulo/core/iterators/DefaultIteratorEnvironment.java
+++ b/core/src/test/java/org/apache/accumulo/core/iterators/DefaultIteratorEnvironment.java
@@ -18,17 +18,16 @@ package org.apache.accumulo.core.iterators;
 
 import java.io.IOException;
 
+import org.apache.accumulo.core.client.impl.BaseIteratorEnvironment;
 import org.apache.accumulo.core.conf.AccumuloConfiguration;
 import org.apache.accumulo.core.data.Key;
 import org.apache.accumulo.core.data.Value;
-import org.apache.accumulo.core.iterators.IteratorUtil.IteratorScope;
 import org.apache.accumulo.core.iterators.system.MapFileIterator;
-import org.apache.accumulo.core.security.Authorizations;
 import org.apache.accumulo.core.util.CachedConfiguration;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FileSystem;
 
-public class DefaultIteratorEnvironment implements IteratorEnvironment {
+public class DefaultIteratorEnvironment extends BaseIteratorEnvironment {
 
   AccumuloConfiguration conf;
 
@@ -53,23 +52,7 @@ public class DefaultIteratorEnvironment implements IteratorEnvironment {
   }
 
   @Override
-  public IteratorScope getIteratorScope() {
-    throw new UnsupportedOperationException();
+  public boolean isSamplingEnabled() {
+    return false;
   }
-
-  @Override
-  public boolean isFullMajorCompaction() {
-    throw new UnsupportedOperationException();
-  }
-
-  @Override
-  public void registerSideChannel(SortedKeyValueIterator<Key,Value> iter) {
-    throw new UnsupportedOperationException();
-  }
-
-  @Override
-  public Authorizations getAuthorizations() {
-    throw new UnsupportedOperationException();
-  }
-
 }

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/core/src/test/java/org/apache/accumulo/core/iterators/FirstEntryInRowIteratorTest.java
----------------------------------------------------------------------
diff --git a/core/src/test/java/org/apache/accumulo/core/iterators/FirstEntryInRowIteratorTest.java b/core/src/test/java/org/apache/accumulo/core/iterators/FirstEntryInRowIteratorTest.java
index 74f7462..5455aa6 100644
--- a/core/src/test/java/org/apache/accumulo/core/iterators/FirstEntryInRowIteratorTest.java
+++ b/core/src/test/java/org/apache/accumulo/core/iterators/FirstEntryInRowIteratorTest.java
@@ -22,14 +22,12 @@ import java.io.IOException;
 import java.util.Collections;
 import java.util.TreeMap;
 
-import org.apache.accumulo.core.conf.AccumuloConfiguration;
+import org.apache.accumulo.core.client.impl.BaseIteratorEnvironment;
 import org.apache.accumulo.core.data.Key;
 import org.apache.accumulo.core.data.PartialKey;
 import org.apache.accumulo.core.data.Range;
 import org.apache.accumulo.core.data.Value;
-import org.apache.accumulo.core.iterators.IteratorUtil.IteratorScope;
 import org.apache.accumulo.core.iterators.system.CountingIterator;
-import org.apache.accumulo.core.security.Authorizations;
 import org.junit.Test;
 
 public class FirstEntryInRowIteratorTest {
@@ -39,38 +37,7 @@ public class FirstEntryInRowIteratorTest {
     org.apache.accumulo.core.iterators.SortedMapIterator source = new SortedMapIterator(sourceMap);
     CountingIterator counter = new CountingIterator(source);
     FirstEntryInRowIterator feiri = new FirstEntryInRowIterator();
-    IteratorEnvironment env = new IteratorEnvironment() {
-
-      @Override
-      public AccumuloConfiguration getConfig() {
-        return null;
-      }
-
-      @Override
-      public IteratorScope getIteratorScope() {
-        return null;
-      }
-
-      @Override
-      public boolean isFullMajorCompaction() {
-        return false;
-      }
-
-      @Override
-      public void registerSideChannel(SortedKeyValueIterator<Key,Value> arg0) {
-
-      }
-
-      @Override
-      public Authorizations getAuthorizations() {
-        return null;
-      }
-
-      @Override
-      public SortedKeyValueIterator<Key,Value> reserveMapFileReader(String arg0) throws IOException {
-        return null;
-      }
-    };
+    IteratorEnvironment env = new BaseIteratorEnvironment();
 
     feiri.init(counter, Collections.singletonMap(FirstEntryInRowIterator.NUM_SCANS_STRING_NAME, Integer.toString(numScans)), env);
 

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/core/src/test/java/org/apache/accumulo/core/iterators/SortedMapIteratorTest.java
----------------------------------------------------------------------
diff --git a/core/src/test/java/org/apache/accumulo/core/iterators/SortedMapIteratorTest.java b/core/src/test/java/org/apache/accumulo/core/iterators/SortedMapIteratorTest.java
new file mode 100644
index 0000000..7557b9a
--- /dev/null
+++ b/core/src/test/java/org/apache/accumulo/core/iterators/SortedMapIteratorTest.java
@@ -0,0 +1,46 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.accumulo.core.iterators;
+
+import java.util.TreeMap;
+
+import org.apache.accumulo.core.client.SampleNotPresentException;
+import org.apache.accumulo.core.client.admin.SamplerConfiguration;
+import org.apache.accumulo.core.client.impl.BaseIteratorEnvironment;
+import org.apache.accumulo.core.data.Key;
+import org.apache.accumulo.core.data.Value;
+import org.apache.accumulo.core.sample.RowSampler;
+import org.junit.Test;
+
+public class SortedMapIteratorTest {
+
+  @Test(expected = SampleNotPresentException.class)
+  public void testSampleNotPresent() {
+    SortedMapIterator smi = new SortedMapIterator(new TreeMap<Key,Value>());
+    smi.deepCopy(new BaseIteratorEnvironment() {
+      @Override
+      public boolean isSamplingEnabled() {
+        return true;
+      }
+
+      @Override
+      public SamplerConfiguration getSamplerConfiguration() {
+        return new SamplerConfiguration(RowSampler.class.getName());
+      }
+    });
+  }
+}

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/core/src/test/java/org/apache/accumulo/core/iterators/user/RowDeletingIteratorTest.java
----------------------------------------------------------------------
diff --git a/core/src/test/java/org/apache/accumulo/core/iterators/user/RowDeletingIteratorTest.java b/core/src/test/java/org/apache/accumulo/core/iterators/user/RowDeletingIteratorTest.java
index a3c1cca..bdaf112 100644
--- a/core/src/test/java/org/apache/accumulo/core/iterators/user/RowDeletingIteratorTest.java
+++ b/core/src/test/java/org/apache/accumulo/core/iterators/user/RowDeletingIteratorTest.java
@@ -16,30 +16,26 @@
  */
 package org.apache.accumulo.core.iterators.user;
 
-import java.io.IOException;
 import java.util.ArrayList;
 import java.util.HashSet;
 import java.util.TreeMap;
 
-import junit.framework.TestCase;
-
-import org.apache.accumulo.core.conf.AccumuloConfiguration;
+import org.apache.accumulo.core.client.impl.BaseIteratorEnvironment;
 import org.apache.accumulo.core.data.ArrayByteSequence;
 import org.apache.accumulo.core.data.ByteSequence;
 import org.apache.accumulo.core.data.Key;
 import org.apache.accumulo.core.data.Range;
 import org.apache.accumulo.core.data.Value;
-import org.apache.accumulo.core.iterators.IteratorEnvironment;
 import org.apache.accumulo.core.iterators.IteratorUtil.IteratorScope;
-import org.apache.accumulo.core.iterators.SortedKeyValueIterator;
 import org.apache.accumulo.core.iterators.SortedMapIterator;
 import org.apache.accumulo.core.iterators.system.ColumnFamilySkippingIterator;
-import org.apache.accumulo.core.security.Authorizations;
 import org.apache.hadoop.io.Text;
 
+import junit.framework.TestCase;
+
 public class RowDeletingIteratorTest extends TestCase {
 
-  public static class TestIE implements IteratorEnvironment {
+  public static class TestIE extends BaseIteratorEnvironment {
 
     private IteratorScope scope;
     private boolean fmc;
@@ -50,11 +46,6 @@ public class RowDeletingIteratorTest extends TestCase {
     }
 
     @Override
-    public AccumuloConfiguration getConfig() {
-      return null;
-    }
-
-    @Override
     public IteratorScope getIteratorScope() {
       return scope;
     }
@@ -63,19 +54,6 @@ public class RowDeletingIteratorTest extends TestCase {
     public boolean isFullMajorCompaction() {
       return fmc;
     }
-
-    @Override
-    public SortedKeyValueIterator<Key,Value> reserveMapFileReader(String mapFileName) throws IOException {
-      return null;
-    }
-
-    @Override
-    public void registerSideChannel(SortedKeyValueIterator<Key,Value> iter) {}
-
-    @Override
-    public Authorizations getAuthorizations() {
-      return null;
-    }
   }
 
   Key nk(String row, String cf, String cq, long time) {

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/core/src/test/java/org/apache/accumulo/core/iterators/user/RowEncodingIteratorTest.java
----------------------------------------------------------------------
diff --git a/core/src/test/java/org/apache/accumulo/core/iterators/user/RowEncodingIteratorTest.java b/core/src/test/java/org/apache/accumulo/core/iterators/user/RowEncodingIteratorTest.java
index 8f228f5..d9aa174 100644
--- a/core/src/test/java/org/apache/accumulo/core/iterators/user/RowEncodingIteratorTest.java
+++ b/core/src/test/java/org/apache/accumulo/core/iterators/user/RowEncodingIteratorTest.java
@@ -16,26 +16,15 @@
  */
 package org.apache.accumulo.core.iterators.user;
 
-import org.apache.accumulo.core.conf.AccumuloConfiguration;
-import org.apache.accumulo.core.data.ByteSequence;
-import org.apache.accumulo.core.data.Key;
-import org.apache.accumulo.core.data.Range;
-import org.apache.accumulo.core.data.Value;
-import org.apache.accumulo.core.iterators.IteratorEnvironment;
-import org.apache.accumulo.core.iterators.IteratorUtil;
-import org.apache.accumulo.core.iterators.SortedKeyValueIterator;
-import org.apache.accumulo.core.iterators.SortedMapIterator;
-import org.apache.accumulo.core.security.Authorizations;
-import org.apache.commons.collections.BufferOverflowException;
-import org.apache.hadoop.io.Text;
-import org.junit.Test;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
 
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.DataInputStream;
 import java.io.DataOutputStream;
 import java.io.IOException;
-
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
@@ -43,23 +32,20 @@ import java.util.Map;
 import java.util.SortedMap;
 import java.util.TreeMap;
 
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
+import org.apache.accumulo.core.client.impl.BaseIteratorEnvironment;
+import org.apache.accumulo.core.data.ByteSequence;
+import org.apache.accumulo.core.data.Key;
+import org.apache.accumulo.core.data.Range;
+import org.apache.accumulo.core.data.Value;
+import org.apache.accumulo.core.iterators.IteratorUtil;
+import org.apache.accumulo.core.iterators.SortedMapIterator;
+import org.apache.commons.collections.BufferOverflowException;
+import org.apache.hadoop.io.Text;
+import org.junit.Test;
 
 public class RowEncodingIteratorTest {
 
-  private static final class DummyIteratorEnv implements IteratorEnvironment {
-    @Override
-    public SortedKeyValueIterator<Key,Value> reserveMapFileReader(String mapFileName) throws IOException {
-      return null;
-    }
-
-    @Override
-    public AccumuloConfiguration getConfig() {
-      return null;
-    }
-
+  private static final class DummyIteratorEnv extends BaseIteratorEnvironment {
     @Override
     public IteratorUtil.IteratorScope getIteratorScope() {
       return IteratorUtil.IteratorScope.scan;
@@ -69,16 +55,6 @@ public class RowEncodingIteratorTest {
     public boolean isFullMajorCompaction() {
       return false;
     }
-
-    @Override
-    public void registerSideChannel(SortedKeyValueIterator<Key,Value> iter) {
-
-    }
-
-    @Override
-    public Authorizations getAuthorizations() {
-      return null;
-    }
   }
 
   private static final class RowEncodingIteratorImpl extends RowEncodingIterator {

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/core/src/test/java/org/apache/accumulo/core/iterators/user/TransformingIteratorTest.java
----------------------------------------------------------------------
diff --git a/core/src/test/java/org/apache/accumulo/core/iterators/user/TransformingIteratorTest.java b/core/src/test/java/org/apache/accumulo/core/iterators/user/TransformingIteratorTest.java
index 1f4d6e7..97ebe5c 100644
--- a/core/src/test/java/org/apache/accumulo/core/iterators/user/TransformingIteratorTest.java
+++ b/core/src/test/java/org/apache/accumulo/core/iterators/user/TransformingIteratorTest.java
@@ -34,7 +34,7 @@ import java.util.SortedMap;
 import java.util.TreeMap;
 
 import org.apache.accumulo.core.client.IteratorSetting;
-import org.apache.accumulo.core.conf.AccumuloConfiguration;
+import org.apache.accumulo.core.client.impl.BaseIteratorEnvironment;
 import org.apache.accumulo.core.data.ArrayByteSequence;
 import org.apache.accumulo.core.data.ByteSequence;
 import org.apache.accumulo.core.data.Key;
@@ -599,7 +599,7 @@ public class TransformingIteratorTest {
   public static class ColFamReversingCompactionKeyTransformingIterator extends ColFamReversingKeyTransformingIterator {
     @Override
     public void init(SortedKeyValueIterator<Key,Value> source, Map<String,String> options, IteratorEnvironment env) throws IOException {
-      env = new MajCIteratorEnvironmentAdapter(env);
+      env = new MajCIteratorEnvironmentAdapter();
       super.init(source, options, env);
     }
   }
@@ -639,7 +639,7 @@ public class TransformingIteratorTest {
   public static class IllegalVisCompactionKeyTransformingIterator extends IllegalVisKeyTransformingIterator {
     @Override
     public void init(SortedKeyValueIterator<Key,Value> source, Map<String,String> options, IteratorEnvironment env) throws IOException {
-      env = new MajCIteratorEnvironmentAdapter(env);
+      env = new MajCIteratorEnvironmentAdapter();
       super.init(source, options, env);
     }
   }
@@ -665,7 +665,7 @@ public class TransformingIteratorTest {
   public static class BadVisCompactionKeyTransformingIterator extends BadVisKeyTransformingIterator {
     @Override
     public void init(SortedKeyValueIterator<Key,Value> source, Map<String,String> options, IteratorEnvironment env) throws IOException {
-      env = new MajCIteratorEnvironmentAdapter(env);
+      env = new MajCIteratorEnvironmentAdapter();
       super.init(source, options, env);
     }
   }
@@ -711,41 +711,10 @@ public class TransformingIteratorTest {
     }
   }
 
-  private static class MajCIteratorEnvironmentAdapter implements IteratorEnvironment {
-    private IteratorEnvironment delegate;
-
-    public MajCIteratorEnvironmentAdapter(IteratorEnvironment delegate) {
-      this.delegate = delegate;
-    }
-
-    @Override
-    public SortedKeyValueIterator<Key,Value> reserveMapFileReader(String mapFileName) throws IOException {
-      return delegate.reserveMapFileReader(mapFileName);
-    }
-
-    @Override
-    public AccumuloConfiguration getConfig() {
-      return delegate.getConfig();
-    }
-
+  private static class MajCIteratorEnvironmentAdapter extends BaseIteratorEnvironment {
     @Override
     public IteratorScope getIteratorScope() {
       return IteratorScope.majc;
     }
-
-    @Override
-    public boolean isFullMajorCompaction() {
-      return delegate.isFullMajorCompaction();
-    }
-
-    @Override
-    public void registerSideChannel(SortedKeyValueIterator<Key,Value> iter) {
-      delegate.registerSideChannel(iter);
-    }
-
-    @Override
-    public Authorizations getAuthorizations() {
-      return null;
-    }
   }
 }

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/core/src/test/resources/org/apache/accumulo/core/file/rfile/ver_7.rf
----------------------------------------------------------------------
diff --git a/core/src/test/resources/org/apache/accumulo/core/file/rfile/ver_7.rf b/core/src/test/resources/org/apache/accumulo/core/file/rfile/ver_7.rf
new file mode 100644
index 0000000..7d2c9f7
Binary files /dev/null and b/core/src/test/resources/org/apache/accumulo/core/file/rfile/ver_7.rf differ

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/docs/src/main/asciidoc/accumulo_user_manual.asciidoc
----------------------------------------------------------------------
diff --git a/docs/src/main/asciidoc/accumulo_user_manual.asciidoc b/docs/src/main/asciidoc/accumulo_user_manual.asciidoc
index 32f19fe..b62983a 100644
--- a/docs/src/main/asciidoc/accumulo_user_manual.asciidoc
+++ b/docs/src/main/asciidoc/accumulo_user_manual.asciidoc
@@ -59,6 +59,8 @@ include::chapters/ssl.txt[]
 
 include::chapters/kerberos.txt[]
 
+include::chapters/sampling.txt[]
+
 include::chapters/administration.txt[]
 
 include::chapters/multivolume.txt[]

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/docs/src/main/asciidoc/chapters/sampling.txt
----------------------------------------------------------------------
diff --git a/docs/src/main/asciidoc/chapters/sampling.txt b/docs/src/main/asciidoc/chapters/sampling.txt
new file mode 100644
index 0000000..f035c56
--- /dev/null
+++ b/docs/src/main/asciidoc/chapters/sampling.txt
@@ -0,0 +1,86 @@
+// Licensed to the Apache Software Foundation (ASF) under one or more
+// contributor license agreements.  See the NOTICE file distributed with
+// this work for additional information regarding copyright ownership.
+// The ASF licenses this file to You under the Apache License, Version 2.0
+// (the "License"); you may not use this file except in compliance with
+// the License.  You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+== Sampling
+
+=== Overview
+
+Accumulo has the ability to generate and scan a per table set of sample data.
+This sample data is kept up to date as a table is mutated.  What key values are
+placed in the sample data is configurable per table.
+
+This feature can be used for query estimation and optimization.  For an example
+of estimaiton assume an Accumulo table is configured to generate a sample
+containing one millionth of a tables data.   If a query is executed against the
+sample and returns one thousand results, then the same query against all the
+data would probably return a billion results.  A nice property of having
+Accumulo generate the sample is that its always up to date.  So estimations
+will be accurate even when querying the most recently written data.
+
+An example of a query optimization is an iterator using sample data to get an
+estimate, and then making decisions based on the estimate.
+
+=== Configuring
+
+Inorder to use sampling, an Accumulo table must be configured with a class that
+implements +org.apache.accumulo.core.sample.Sampler+ along with options for
+that class.  For guidance on implementing a Sampler see that interface's
+javadoc.  Accumulo provides a few implementations out of the box.   For
+information on how to use the samplers that ship with Accumulo look in the
+package `org.apache.accumulo.core.sample` and consult the javadoc of the
+classes there.  See +README.sample+ and +SampleExample.java+ for examples of
+how to configure a Sampler on a table.
+
+Once a table is configured with a sampler all writes after that point will
+generate sample data.  For data written before sampling was configured sample
+data will not be present.  A compaction can be initiated that only compacts the
+files in the table that do not have sample data.   The example readme shows how
+to do this.
+
+If the sampling configuration of a table is changed, then Accumulo will start
+generating new sample data with the new configuration.   However old data will
+still have sample data generated with the previous configuration.  A selective
+compaction can also be issued in this case to regenerate the sample data.
+
+=== Scanning sample data
+
+Inorder to scan sample data, use the +setSamplerConfiguration(...)+  method on
++Scanner+ or +BatchScanner+.  Please consult this methods javadocs for more
+information.
+
+Sample data can also be scanned from within an Accumulo
++SortedKeyValueIterator+.  To see how to do this look at the example iterator
+referenced in README.sample.  Also, consult the javadoc on
++org.apache.accumulo.core.iterators.IteratorEnvironment.cloneWithSamplingEnabled()+.
+
+Map reduce jobs using the +AccumuloInputFormat+ can also read sample data.  See
+the javadoc for the +setSamplerConfiguration()+ method on
++AccumuloInputFormat+.
+
+Scans over sample data will throw a +SampleNotPresentException+ in the following cases :
+
+. sample data is not present,
+. sample data is present but was generated with multiple configurations
+. sample data is partially present
+
+So a scan over sample data can only succeed if all data written has sample data
+generated with the same configuration.
+
+=== Bulk import
+
+When generating rfiles to bulk import into Accumulo, those rfiles can contain
+sample data.  To use this feature, look at the javadoc on the
++AccumuloFileOutputFormat.setSampler(...)+ method.
+

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/docs/src/main/resources/examples/README
----------------------------------------------------------------------
diff --git a/docs/src/main/resources/examples/README b/docs/src/main/resources/examples/README
index 4211050..03c2e05 100644
--- a/docs/src/main/resources/examples/README
+++ b/docs/src/main/resources/examples/README
@@ -80,6 +80,8 @@ features of Apache Accumulo.
    README.rowhash:     Using MapReduce to read a table and write to a new
                        column in the same table.
 
+   README.sample:      Building and using sample data in Accumulo.
+
    README.shard:       Using the intersecting iterator with a term index
                        partitioned by document.
 

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/docs/src/main/resources/examples/README.sample
----------------------------------------------------------------------
diff --git a/docs/src/main/resources/examples/README.sample b/docs/src/main/resources/examples/README.sample
new file mode 100644
index 0000000..15288aa
--- /dev/null
+++ b/docs/src/main/resources/examples/README.sample
@@ -0,0 +1,192 @@
+Title: Apache Accumulo Batch Writing and Scanning Example
+Notice:    Licensed to the Apache Software Foundation (ASF) under one
+           or more contributor license agreements.  See the NOTICE file
+           distributed with this work for additional information
+           regarding copyright ownership.  The ASF licenses this file
+           to you under the Apache License, Version 2.0 (the
+           "License"); you may not use this file except in compliance
+           with the License.  You may obtain a copy of the License at
+           .
+             http://www.apache.org/licenses/LICENSE-2.0
+           .
+           Unless required by applicable law or agreed to in writing,
+           software distributed under the License is distributed on an
+           "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+           KIND, either express or implied.  See the License for the
+           specific language governing permissions and limitations
+           under the License.
+
+
+Basic Sampling Example
+----------------------
+
+Accumulo supports building a set of sample data that can be efficiently
+accessed by scanners.  What data is included in the sample set is configurable.
+Below, some data representing documents are inserted.  
+
+    root@instance sampex> createtable sampex
+    root@instance sampex> insert 9255 doc content 'abcde'
+    root@instance sampex> insert 9255 doc url file://foo.txt
+    root@instance sampex> insert 8934 doc content 'accumulo scales'
+    root@instance sampex> insert 8934 doc url file://accumulo_notes.txt
+    root@instance sampex> insert 2317 doc content 'milk, eggs, bread, parmigiano-reggiano'
+    root@instance sampex> insert 2317 doc url file://groceries/9.txt
+    root@instance sampex> insert 3900 doc content 'EC2 ate my homework'
+    root@instance sampex> insert 3900 doc uril file://final_project.txt
+
+Below the table sampex is configured to build a sample set.  The configuration
+causes Accumulo to include any row where `murmur3_32(row) % 3 ==0` in the
+tables sample data.
+
+    root@instance sampex> config -t sampex -s table.sampler.opt.hasher=murmur3_32
+    root@instance sampex> config -t sampex -s table.sampler.opt.modulus=3
+    root@instance sampex> config -t sampex -s table.sampler=org.apache.accumulo.core.sample.RowSampler
+
+Below, attempting to scan the sample returns an error.  This is because data
+was inserted before the sample set was configured.
+
+    root@instance sampex> scan --sample
+    2015-09-09 12:21:50,643 [shell.Shell] ERROR: org.apache.accumulo.core.client.SampleNotPresentException: Table sampex(ID:2) does not have sampling configured or built
+
+To remedy this problem, the following command will flush in memory data and
+compact any files that do not contain the correct sample data.   
+
+    root@instance sampex> compact -t sampex --sf-no-sample
+
+After the compaction, the sample scan works.  
+
+    root@instance sampex> scan --sample
+    2317 doc:content []    milk, eggs, bread, parmigiano-reggiano
+    2317 doc:url []    file://groceries/9.txt
+
+The commands below show that updates to data in the sample are seen when
+scanning the sample.
+
+    root@instance sampex> insert 2317 doc content 'milk, eggs, bread, parmigiano-reggiano, butter'
+    root@instance sampex> scan --sample
+    2317 doc:content []    milk, eggs, bread, parmigiano-reggiano, butter
+    2317 doc:url []    file://groceries/9.txt
+
+Inorder to make scanning the sample fast, sample data is partitioned as data is
+written to Accumulo.  This means if the sample configuration is changed, that
+data written previously is partitioned using a different criteria.  Accumulo
+will detect this situation and fail sample scans.  The commands below show this
+failure and fixiing the problem with a compaction.
+
+    root@instance sampex> config -t sampex -s table.sampler.opt.modulus=2
+    root@instance sampex> scan --sample
+    2015-09-09 12:22:51,058 [shell.Shell] ERROR: org.apache.accumulo.core.client.SampleNotPresentException: Table sampex(ID:2) does not have sampling configured or built
+    root@instance sampex> compact -t sampex --sf-no-sample
+    2015-09-09 12:23:07,242 [shell.Shell] INFO : Compaction of table sampex started for given range
+    root@instance sampex> scan --sample
+    2317 doc:content []    milk, eggs, bread, parmigiano-reggiano
+    2317 doc:url []    file://groceries/9.txt
+    3900 doc:content []    EC2 ate my homework
+    3900 doc:uril []    file://final_project.txt
+    9255 doc:content []    abcde
+    9255 doc:url []    file://foo.txt
+
+The example above is replicated in a java program using the Accumulo API.
+Below is the program name and the command to run it.
+
+    ./bin/accumulo org.apache.accumulo.examples.simple.sample.SampleExample -i instance -z localhost -u root -p secret
+
+The commands below look under the hood to give some insight into how this
+feature works.  The commands determine what files the sampex table is using.
+
+    root@instance sampex> tables -l
+    accumulo.metadata    =>        !0
+    accumulo.replication =>      +rep
+    accumulo.root        =>        +r
+    sampex               =>         2
+    trace                =>         1
+    root@instance sampex> scan -t accumulo.metadata -c file -b 2 -e 2<
+    2< file:hdfs://localhost:10000/accumulo/tables/2/default_tablet/A000000s.rf []    702,8
+
+Below shows running `accumulo rfile-info` on the file above.  This shows the
+rfile has a normal default locality group and a sample default locality group.
+The output also shows the configuration used to create the sample locality
+group.  The sample configuration within a rfile must match the tables sample
+configuration for sample scan to work.
+
+    $ ./bin/accumulo rfile-info hdfs://localhost:10000/accumulo/tables/2/default_tablet/A000000s.rf
+    Reading file: hdfs://localhost:10000/accumulo/tables/2/default_tablet/A000000s.rf
+    RFile Version            : 8
+    
+    Locality group           : <DEFAULT>
+    	Start block            : 0
+    	Num   blocks           : 1
+    	Index level 0          : 35 bytes  1 blocks
+    	First key              : 2317 doc:content [] 1437672014986 false
+    	Last key               : 9255 doc:url [] 1437672014875 false
+    	Num entries            : 8
+    	Column families        : [doc]
+    
+    Sample Configuration     :
+    	Sampler class          : org.apache.accumulo.core.sample.RowSampler
+    	Sampler options        : {hasher=murmur3_32, modulus=2}
+
+    Sample Locality group    : <DEFAULT>
+    	Start block            : 0
+    	Num   blocks           : 1
+    	Index level 0          : 36 bytes  1 blocks
+    	First key              : 2317 doc:content [] 1437672014986 false
+    	Last key               : 9255 doc:url [] 1437672014875 false
+    	Num entries            : 6
+    	Column families        : [doc]
+    
+    Meta block     : BCFile.index
+          Raw size             : 4 bytes
+          Compressed size      : 12 bytes
+          Compression type     : gz
+
+    Meta block     : RFile.index
+          Raw size             : 309 bytes
+          Compressed size      : 176 bytes
+          Compression type     : gz
+
+
+Shard Sampling Example
+-------------------------
+
+`README.shard` shows how to index and search files using Accumulo.  That
+example indexes documents into a table named `shard`.  The indexing scheme used
+in that example places the document name in the column qualifier.  A useful
+sample of this indexing scheme should contain all data for any document in the
+sample.   To accomplish this, the following commands build a sample for the
+shard table based on the column qualifier.
+
+    root@instance shard> config -t shard -s table.sampler.opt.hasher=murmur3_32
+    root@instance shard> config -t shard -s table.sampler.opt.modulus=101
+    root@instance shard> config -t shard -s table.sampler.opt.qualifier=true
+    root@instance shard> config -t shard -s table.sampler=org.apache.accumulo.core.sample.RowColumnSampler
+    root@instance shard> compact -t shard --sf-no-sample -w
+    2015-07-23 15:00:09,280 [shell.Shell] INFO : Compacting table ...
+    2015-07-23 15:00:10,134 [shell.Shell] INFO : Compaction of table shard completed for given range
+
+After enabling sampling, the command below counts the number of documents in
+the sample containing the words `import` and `int`.     
+
+    $ ./bin/accumulo org.apache.accumulo.examples.simple.shard.Query --sample -i instance16 -z localhost -t shard -u root -p secret import int | fgrep '.java' | wc
+         11      11    1246
+
+The command below counts the total number of documents containing the words
+`import` and `int`.
+
+    $ ./bin/accumulo org.apache.accumulo.examples.simple.shard.Query -i instance16 -z localhost -t shard -u root -p secret import int | fgrep '.java' | wc
+       1085    1085  118175
+
+The counts 11 out of 1085 total are around what would be expected for a modulus
+of 101.  Querying the sample first provides a quick way to estimate how much data
+the real query will bring back. 
+
+Another way sample data could be used with the shard example is with a
+specialized iterator.  In the examples source code there is an iterator named
+CutoffIntersectingIterator.  This iterator first checks how many documents are
+found in the sample data.  If too many documents are found in the sample data,
+then it returns nothing.   Otherwise it proceeds to query the full data set.
+To experiment with this iterator, use the following command.  The
+`--sampleCutoff` option below will cause the query to return nothing if based
+on the sample it appears a query would return more than 1000 documents.
+
+    $ ./bin/accumulo org.apache.accumulo.examples.simple.shard.Query --sampleCutoff 1000 -i instance16 -z localhost -t shard -u root -p secret import int | fgrep '.java' | wc

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/examples/simple/src/main/java/org/apache/accumulo/examples/simple/sample/SampleExample.java
----------------------------------------------------------------------
diff --git a/examples/simple/src/main/java/org/apache/accumulo/examples/simple/sample/SampleExample.java b/examples/simple/src/main/java/org/apache/accumulo/examples/simple/sample/SampleExample.java
new file mode 100644
index 0000000..57d77b1
--- /dev/null
+++ b/examples/simple/src/main/java/org/apache/accumulo/examples/simple/sample/SampleExample.java
@@ -0,0 +1,150 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.accumulo.examples.simple.sample;
+
+import java.util.Collections;
+import java.util.Map.Entry;
+
+import org.apache.accumulo.core.cli.BatchWriterOpts;
+import org.apache.accumulo.core.cli.ClientOnDefaultTable;
+import org.apache.accumulo.core.client.BatchWriter;
+import org.apache.accumulo.core.client.Connector;
+import org.apache.accumulo.core.client.SampleNotPresentException;
+import org.apache.accumulo.core.client.Scanner;
+import org.apache.accumulo.core.client.admin.CompactionConfig;
+import org.apache.accumulo.core.client.admin.CompactionStrategyConfig;
+import org.apache.accumulo.core.client.admin.SamplerConfiguration;
+import org.apache.accumulo.core.data.Key;
+import org.apache.accumulo.core.data.Mutation;
+import org.apache.accumulo.core.data.Value;
+import org.apache.accumulo.core.sample.RowSampler;
+import org.apache.accumulo.core.security.Authorizations;
+import org.apache.accumulo.examples.simple.client.RandomBatchWriter;
+import org.apache.accumulo.examples.simple.shard.CutoffIntersectingIterator;
+
+import com.google.common.collect.ImmutableMap;
+
+/**
+ * A simple example of using Accumulo's sampling feature. This example does something similar to what README.sample shows using the shell. Also see
+ * {@link CutoffIntersectingIterator} and README.sample for an example of how to use sample data from within an iterator.
+ */
+public class SampleExample {
+
+  // a compaction strategy that only selects files for compaction that have no sample data or sample data created in a different way than the tables
+  static final CompactionStrategyConfig NO_SAMPLE_STRATEGY = new CompactionStrategyConfig(
+      "org.apache.accumulo.tserver.compaction.strategies.ConfigurableCompactionStrategy").setOptions(Collections.singletonMap("SF_NO_SAMPLE", ""));
+
+  static class Opts extends ClientOnDefaultTable {
+    public Opts() {
+      super("sampex");
+    }
+  }
+
+  public static void main(String[] args) throws Exception {
+    Opts opts = new Opts();
+    BatchWriterOpts bwOpts = new BatchWriterOpts();
+    opts.parseArgs(RandomBatchWriter.class.getName(), args, bwOpts);
+
+    Connector conn = opts.getConnector();
+
+    if (!conn.tableOperations().exists(opts.getTableName())) {
+      conn.tableOperations().create(opts.getTableName());
+    } else {
+      System.out.println("Table exists, not doing anything.");
+      return;
+    }
+
+    // write some data
+    BatchWriter bw = conn.createBatchWriter(opts.getTableName(), bwOpts.getBatchWriterConfig());
+    bw.addMutation(createMutation("9225", "abcde", "file://foo.txt"));
+    bw.addMutation(createMutation("8934", "accumulo scales", "file://accumulo_notes.txt"));
+    bw.addMutation(createMutation("2317", "milk, eggs, bread, parmigiano-reggiano", "file://groceries/9/txt"));
+    bw.addMutation(createMutation("3900", "EC2 ate my homework", "file://final_project.txt"));
+    bw.flush();
+
+    SamplerConfiguration sc1 = new SamplerConfiguration(RowSampler.class.getName());
+    sc1.setOptions(ImmutableMap.of("hasher", "murmur3_32", "modulus", "3"));
+
+    conn.tableOperations().setSamplerConfiguration(opts.getTableName(), sc1);
+
+    Scanner scanner = conn.createScanner(opts.getTableName(), Authorizations.EMPTY);
+    System.out.println("Scanning all data :");
+    print(scanner);
+    System.out.println();
+
+    System.out.println("Scanning with sampler configuration.  Data was written before sampler was set on table, scan should fail.");
+    scanner.setSamplerConfiguration(sc1);
+    try {
+      print(scanner);
+    } catch (SampleNotPresentException e) {
+      System.out.println("  Saw sample not present exception as expected.");
+    }
+    System.out.println();
+
+    // compact table to recreate sample data
+    conn.tableOperations().compact(opts.getTableName(), new CompactionConfig().setCompactionStrategy(NO_SAMPLE_STRATEGY));
+
+    System.out.println("Scanning after compaction (compaction should have created sample data) : ");
+    print(scanner);
+    System.out.println();
+
+    // update a document in the sample data
+    bw.addMutation(createMutation("2317", "milk, eggs, bread, parmigiano-reggiano, butter", "file://groceries/9/txt"));
+    bw.close();
+    System.out.println("Scanning sample after updating content for docId 2317 (should see content change in sample data) : ");
+    print(scanner);
+    System.out.println();
+
+    // change tables sampling configuration...
+    SamplerConfiguration sc2 = new SamplerConfiguration(RowSampler.class.getName());
+    sc2.setOptions(ImmutableMap.of("hasher", "murmur3_32", "modulus", "2"));
+    conn.tableOperations().setSamplerConfiguration(opts.getTableName(), sc2);
+    // compact table to recreate sample data using new configuration
+    conn.tableOperations().compact(opts.getTableName(), new CompactionConfig().setCompactionStrategy(NO_SAMPLE_STRATEGY));
+
+    System.out.println("Scanning with old sampler configuration.  Sample data was created using new configuration with a compaction.  Scan should fail.");
+    try {
+      // try scanning with old sampler configuration
+      print(scanner);
+    } catch (SampleNotPresentException e) {
+      System.out.println("  Saw sample not present exception as expected ");
+    }
+    System.out.println();
+
+    // update expected sampler configuration on scanner
+    scanner.setSamplerConfiguration(sc2);
+
+    System.out.println("Scanning with new sampler configuration : ");
+    print(scanner);
+    System.out.println();
+
+  }
+
+  private static void print(Scanner scanner) {
+    for (Entry<Key,Value> entry : scanner) {
+      System.out.println("  " + entry.getKey() + " " + entry.getValue());
+    }
+  }
+
+  private static Mutation createMutation(String docId, String content, String url) {
+    Mutation m = new Mutation(docId);
+    m.put("doc", "context", content);
+    m.put("doc", "url", url);
+    return m;
+  }
+}

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/examples/simple/src/main/java/org/apache/accumulo/examples/simple/shard/CutoffIntersectingIterator.java
----------------------------------------------------------------------
diff --git a/examples/simple/src/main/java/org/apache/accumulo/examples/simple/shard/CutoffIntersectingIterator.java b/examples/simple/src/main/java/org/apache/accumulo/examples/simple/shard/CutoffIntersectingIterator.java
new file mode 100644
index 0000000..133e8ae
--- /dev/null
+++ b/examples/simple/src/main/java/org/apache/accumulo/examples/simple/shard/CutoffIntersectingIterator.java
@@ -0,0 +1,123 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.accumulo.examples.simple.shard;
+
+import java.io.IOException;
+import java.util.Collection;
+import java.util.Map;
+
+import org.apache.accumulo.core.client.IteratorSetting;
+import org.apache.accumulo.core.client.admin.SamplerConfiguration;
+import org.apache.accumulo.core.data.ByteSequence;
+import org.apache.accumulo.core.data.Key;
+import org.apache.accumulo.core.data.Range;
+import org.apache.accumulo.core.data.Value;
+import org.apache.accumulo.core.iterators.IteratorEnvironment;
+import org.apache.accumulo.core.iterators.SortedKeyValueIterator;
+import org.apache.accumulo.core.iterators.user.IntersectingIterator;
+import org.apache.accumulo.core.sample.RowColumnSampler;
+
+import com.google.common.base.Preconditions;
+
+/**
+ * This iterator uses a sample built from the Column Qualifier to quickly avoid intersecting iterator queries that may return too many documents.
+ */
+
+public class CutoffIntersectingIterator extends IntersectingIterator {
+
+  private IntersectingIterator sampleII;
+  private int sampleMax;
+  private boolean hasTop;
+
+  public static void setCutoff(IteratorSetting iterCfg, int cutoff) {
+    Preconditions.checkArgument(cutoff >= 0);
+    iterCfg.addOption("cutoff", cutoff + "");
+  }
+
+  @Override
+  public boolean hasTop() {
+    return hasTop && super.hasTop();
+  }
+
+  @Override
+  public void seek(Range range, Collection<ByteSequence> seekColumnFamilies, boolean inclusive) throws IOException {
+
+    sampleII.seek(range, seekColumnFamilies, inclusive);
+
+    // this check will be redone whenever iterator stack is torn down and recreated.
+    int count = 0;
+    while (count <= sampleMax && sampleII.hasTop()) {
+      sampleII.next();
+      count++;
+    }
+
+    if (count > sampleMax) {
+      // In a real application would probably want to return a key value that indicates too much data. Since this would execute for each tablet, some tablets
+      // may return data. For tablets that did not return data, would want an indication.
+      hasTop = false;
+    } else {
+      hasTop = true;
+      super.seek(range, seekColumnFamilies, inclusive);
+    }
+  }
+
+  @Override
+  public void init(SortedKeyValueIterator<Key,Value> source, Map<String,String> options, IteratorEnvironment env) throws IOException {
+    super.init(source, options, env);
+
+    IteratorEnvironment sampleEnv = env.cloneWithSamplingEnabled();
+
+    setMax(sampleEnv, options);
+
+    SortedKeyValueIterator<Key,Value> sampleDC = source.deepCopy(sampleEnv);
+    sampleII = new IntersectingIterator();
+    sampleII.init(sampleDC, options, env);
+
+  }
+
+  static void validateSamplerConfig(SamplerConfiguration sampleConfig) {
+    Preconditions.checkNotNull(sampleConfig);
+    Preconditions.checkArgument(sampleConfig.getSamplerClassName().equals(RowColumnSampler.class.getName()),
+        "Unexpected Sampler " + sampleConfig.getSamplerClassName());
+    Preconditions.checkArgument(sampleConfig.getOptions().get("qualifier").equals("true"), "Expected sample on column qualifier");
+    Preconditions.checkArgument(isNullOrFalse(sampleConfig.getOptions(), "row", "family", "visibility"), "Expected sample on column qualifier only");
+  }
+
+  private void setMax(IteratorEnvironment sampleEnv, Map<String,String> options) {
+    String cutoffValue = options.get("cutoff");
+    SamplerConfiguration sampleConfig = sampleEnv.getSamplerConfiguration();
+
+    // Ensure the sample was constructed in an expected way. If the sample is not built as expected, then can not draw conclusions based on sample.
+    Preconditions.checkNotNull(cutoffValue, "Expected cutoff option is missing");
+    validateSamplerConfig(sampleConfig);
+
+    int modulus = Integer.parseInt(sampleConfig.getOptions().get("modulus"));
+
+    sampleMax = Math.round(Float.parseFloat(cutoffValue) / modulus);
+  }
+
+  private static boolean isNullOrFalse(Map<String,String> options, String... keys) {
+    for (String key : keys) {
+      String val = options.get(key);
+      if (val != null && val.equals("true")) {
+        return false;
+      }
+    }
+    return true;
+  }
+}

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/examples/simple/src/main/java/org/apache/accumulo/examples/simple/shard/Query.java
----------------------------------------------------------------------
diff --git a/examples/simple/src/main/java/org/apache/accumulo/examples/simple/shard/Query.java b/examples/simple/src/main/java/org/apache/accumulo/examples/simple/shard/Query.java
index 41d5dc7..7925855 100644
--- a/examples/simple/src/main/java/org/apache/accumulo/examples/simple/shard/Query.java
+++ b/examples/simple/src/main/java/org/apache/accumulo/examples/simple/shard/Query.java
@@ -27,6 +27,7 @@ import org.apache.accumulo.core.cli.ClientOnRequiredTable;
 import org.apache.accumulo.core.client.BatchScanner;
 import org.apache.accumulo.core.client.Connector;
 import org.apache.accumulo.core.client.IteratorSetting;
+import org.apache.accumulo.core.client.admin.SamplerConfiguration;
 import org.apache.accumulo.core.data.Key;
 import org.apache.accumulo.core.data.Range;
 import org.apache.accumulo.core.data.Value;
@@ -46,16 +47,32 @@ public class Query {
   static class Opts extends ClientOnRequiredTable {
     @Parameter(description = " term { <term> ... }")
     List<String> terms = new ArrayList<String>();
+
+    @Parameter(names = {"--sample"}, description = "Do queries against sample, useful when sample is built using column qualifier")
+    private boolean useSample = false;
+
+    @Parameter(names = {"--sampleCutoff"},
+        description = "Use sample data to determine if a query might return a number of documents over the cutoff.  This check is per tablet.")
+    private Integer sampleCutoff = null;
   }
 
-  public static List<String> query(BatchScanner bs, List<String> terms) {
+  public static List<String> query(BatchScanner bs, List<String> terms, Integer cutoff) {
 
     Text columns[] = new Text[terms.size()];
     int i = 0;
     for (String term : terms) {
       columns[i++] = new Text(term);
     }
-    IteratorSetting ii = new IteratorSetting(20, "ii", IntersectingIterator.class);
+
+    IteratorSetting ii;
+
+    if (cutoff != null) {
+      ii = new IteratorSetting(20, "ii", CutoffIntersectingIterator.class);
+      CutoffIntersectingIterator.setCutoff(ii, cutoff);
+    } else {
+      ii = new IteratorSetting(20, "ii", IntersectingIterator.class);
+    }
+
     IntersectingIterator.setColumnFamilies(ii, columns);
     bs.addScanIterator(ii);
     bs.setRanges(Collections.singleton(new Range()));
@@ -73,9 +90,15 @@ public class Query {
     Connector conn = opts.getConnector();
     BatchScanner bs = conn.createBatchScanner(opts.getTableName(), opts.auths, bsOpts.scanThreads);
     bs.setTimeout(bsOpts.scanTimeout, TimeUnit.MILLISECONDS);
-
-    for (String entry : query(bs, opts.terms))
+    if (opts.useSample) {
+      SamplerConfiguration samplerConfig = conn.tableOperations().getSamplerConfiguration(opts.getTableName());
+      CutoffIntersectingIterator.validateSamplerConfig(conn.tableOperations().getSamplerConfiguration(opts.getTableName()));
+      bs.setSamplerConfiguration(samplerConfig);
+    }
+    for (String entry : query(bs, opts.terms, opts.sampleCutoff))
       System.out.println("  " + entry);
+
+    bs.close();
   }
 
 }

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/server/base/src/main/java/org/apache/accumulo/server/util/VerifyTabletAssignments.java
----------------------------------------------------------------------
diff --git a/server/base/src/main/java/org/apache/accumulo/server/util/VerifyTabletAssignments.java b/server/base/src/main/java/org/apache/accumulo/server/util/VerifyTabletAssignments.java
index 0d7ade8..d2d6664 100644
--- a/server/base/src/main/java/org/apache/accumulo/server/util/VerifyTabletAssignments.java
+++ b/server/base/src/main/java/org/apache/accumulo/server/util/VerifyTabletAssignments.java
@@ -189,7 +189,7 @@ public class VerifyTabletAssignments {
     List<IterInfo> emptyListIterInfo = Collections.emptyList();
     List<TColumn> emptyListColumn = Collections.emptyList();
     InitialMultiScan is = client.startMultiScan(tinfo, context.rpcCreds(), batch, emptyListColumn, emptyListIterInfo, emptyMapSMapSS,
-        Authorizations.EMPTY.getAuthorizationsBB(), false, 0L);
+        Authorizations.EMPTY.getAuthorizationsBB(), false, null, 0L);
     if (is.result.more) {
       MultiScanResult result = client.continueMultiScan(tinfo, is.scanID);
       checkFailures(entry.getKey(), failures, result);

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/server/base/src/test/java/org/apache/accumulo/server/iterators/MetadataBulkLoadFilterTest.java
----------------------------------------------------------------------
diff --git a/server/base/src/test/java/org/apache/accumulo/server/iterators/MetadataBulkLoadFilterTest.java b/server/base/src/test/java/org/apache/accumulo/server/iterators/MetadataBulkLoadFilterTest.java
index 7e9543f..1b30530 100644
--- a/server/base/src/test/java/org/apache/accumulo/server/iterators/MetadataBulkLoadFilterTest.java
+++ b/server/base/src/test/java/org/apache/accumulo/server/iterators/MetadataBulkLoadFilterTest.java
@@ -21,18 +21,15 @@ import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.TreeMap;
 
-import org.apache.accumulo.core.conf.AccumuloConfiguration;
+import org.apache.accumulo.core.client.impl.BaseIteratorEnvironment;
 import org.apache.accumulo.core.data.ByteSequence;
 import org.apache.accumulo.core.data.Key;
 import org.apache.accumulo.core.data.Range;
 import org.apache.accumulo.core.data.Value;
-import org.apache.accumulo.core.iterators.IteratorEnvironment;
 import org.apache.accumulo.core.iterators.IteratorUtil.IteratorScope;
-import org.apache.accumulo.core.iterators.SortedKeyValueIterator;
 import org.apache.accumulo.core.iterators.SortedMapIterator;
 import org.apache.accumulo.core.metadata.schema.MetadataSchema.TabletsSection;
 import org.apache.accumulo.core.metadata.schema.MetadataSchema.TabletsSection.DataFileColumnFamily;
-import org.apache.accumulo.core.security.Authorizations;
 import org.apache.accumulo.core.util.ColumnFQ;
 import org.apache.accumulo.fate.zookeeper.TransactionWatcher.Arbitrator;
 import org.apache.hadoop.io.Text;
@@ -104,20 +101,7 @@ public class MetadataBulkLoadFilterTest {
     put(tm1, "2<", TabletsSection.BulkFileColumnFamily.NAME, "/t2/fileA", "2");
 
     TestMetadataBulkLoadFilter iter = new TestMetadataBulkLoadFilter();
-    iter.init(new SortedMapIterator(tm1), new HashMap<String,String>(), new IteratorEnvironment() {
-
-      @Override
-      public SortedKeyValueIterator<Key,Value> reserveMapFileReader(String mapFileName) throws IOException {
-        return null;
-      }
-
-      @Override
-      public void registerSideChannel(SortedKeyValueIterator<Key,Value> iter) {}
-
-      @Override
-      public Authorizations getAuthorizations() {
-        return null;
-      }
+    iter.init(new SortedMapIterator(tm1), new HashMap<String,String>(), new BaseIteratorEnvironment() {
 
       @Override
       public boolean isFullMajorCompaction() {
@@ -128,11 +112,6 @@ public class MetadataBulkLoadFilterTest {
       public IteratorScope getIteratorScope() {
         return IteratorScope.majc;
       }
-
-      @Override
-      public AccumuloConfiguration getConfig() {
-        return null;
-      }
     });
 
     iter.seek(new Range(), new ArrayList<ByteSequence>(), false);

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/server/base/src/test/java/org/apache/accumulo/server/replication/StatusCombinerTest.java
----------------------------------------------------------------------
diff --git a/server/base/src/test/java/org/apache/accumulo/server/replication/StatusCombinerTest.java b/server/base/src/test/java/org/apache/accumulo/server/replication/StatusCombinerTest.java
index f4d5a9b..26ad8de 100644
--- a/server/base/src/test/java/org/apache/accumulo/server/replication/StatusCombinerTest.java
+++ b/server/base/src/test/java/org/apache/accumulo/server/replication/StatusCombinerTest.java
@@ -24,16 +24,10 @@ import java.util.List;
 
 import org.apache.accumulo.core.client.IteratorSetting;
 import org.apache.accumulo.core.client.IteratorSetting.Column;
-import org.apache.accumulo.core.conf.AccumuloConfiguration;
 import org.apache.accumulo.core.data.Key;
-import org.apache.accumulo.core.data.Value;
 import org.apache.accumulo.core.iterators.Combiner;
 import org.apache.accumulo.core.iterators.DevNull;
-import org.apache.accumulo.core.iterators.IteratorEnvironment;
-import org.apache.accumulo.core.iterators.IteratorUtil.IteratorScope;
-import org.apache.accumulo.core.iterators.SortedKeyValueIterator;
 import org.apache.accumulo.core.replication.ReplicationSchema.StatusSection;
-import org.apache.accumulo.core.security.Authorizations;
 import org.apache.accumulo.server.replication.proto.Replication.Status;
 import org.junit.Assert;
 import org.junit.Before;
@@ -52,38 +46,7 @@ public class StatusCombinerTest {
     builder = Status.newBuilder();
     IteratorSetting cfg = new IteratorSetting(50, StatusCombiner.class);
     Combiner.setColumns(cfg, Collections.singletonList(new Column(StatusSection.NAME)));
-    combiner.init(new DevNull(), cfg.getOptions(), new IteratorEnvironment() {
-
-      @Override
-      public AccumuloConfiguration getConfig() {
-        return null;
-      }
-
-      @Override
-      public IteratorScope getIteratorScope() {
-        return null;
-      }
-
-      @Override
-      public boolean isFullMajorCompaction() {
-        return false;
-      }
-
-      @Override
-      public void registerSideChannel(SortedKeyValueIterator<Key,Value> arg0) {
-
-      }
-
-      @Override
-      public Authorizations getAuthorizations() {
-        return null;
-      }
-
-      @Override
-      public SortedKeyValueIterator<Key,Value> reserveMapFileReader(String arg0) throws IOException {
-        return null;
-      }
-    });
+    combiner.init(new DevNull(), cfg.getOptions(), null);
   }
 
   @Test

http://git-wip-us.apache.org/repos/asf/accumulo/blob/45f18c17/server/monitor/src/main/java/org/apache/accumulo/monitor/servlets/trace/NullScanner.java
----------------------------------------------------------------------
diff --git a/server/monitor/src/main/java/org/apache/accumulo/monitor/servlets/trace/NullScanner.java b/server/monitor/src/main/java/org/apache/accumulo/monitor/servlets/trace/NullScanner.java
index 750ad8e..2c46835 100644
--- a/server/monitor/src/main/java/org/apache/accumulo/monitor/servlets/trace/NullScanner.java
+++ b/server/monitor/src/main/java/org/apache/accumulo/monitor/servlets/trace/NullScanner.java
@@ -23,6 +23,7 @@ import java.util.concurrent.TimeUnit;
 import org.apache.accumulo.core.client.IteratorSetting;
 import org.apache.accumulo.core.client.IteratorSetting.Column;
 import org.apache.accumulo.core.client.Scanner;
+import org.apache.accumulo.core.client.admin.SamplerConfiguration;
 import org.apache.accumulo.core.data.Key;
 import org.apache.accumulo.core.data.Range;
 import org.apache.accumulo.core.data.Value;
@@ -134,4 +135,14 @@ public class NullScanner implements Scanner {
     return 0;
   }
 
+  @Override
+  public void setSamplerConfiguration(SamplerConfiguration samplerConfig) {}
+
+  @Override
+  public SamplerConfiguration getSamplerConfiguration() {
+    return null;
+  }
+
+  @Override
+  public void clearSamplerConfiguration() {}
 }