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Posted to dev@drill.apache.org by ja...@apache.org on 2014/05/04 18:55:32 UTC
[10/21] git commit: DRILL-578: Performance fixes in Hash Join.
DRILL-578: Performance fixes in Hash Join.
Includes a few minor fixes when hash join receives empty batches on build / probe side
Project: http://git-wip-us.apache.org/repos/asf/incubator-drill/repo
Commit: http://git-wip-us.apache.org/repos/asf/incubator-drill/commit/5603a633
Tree: http://git-wip-us.apache.org/repos/asf/incubator-drill/tree/5603a633
Diff: http://git-wip-us.apache.org/repos/asf/incubator-drill/diff/5603a633
Branch: refs/heads/master
Commit: 5603a633f1de15af05e011ab6216300c6b0bd775
Parents: beeaf9e
Author: Mehant Baid <me...@gmail.com>
Authored: Wed Apr 23 16:12:04 2014 -0700
Committer: Jacques Nadeau <ja...@apache.org>
Committed: Sat May 3 18:48:08 2014 -0700
----------------------------------------------------------------------
.../drill/exec/physical/config/HashJoinPOP.java | 22 ----
.../exec/physical/impl/join/HashJoinBatch.java | 115 +++++++++++++------
.../exec/physical/impl/join/HashJoinHelper.java | 38 +++---
.../exec/physical/impl/join/HashJoinProbe.java | 3 +-
.../impl/join/HashJoinProbeTemplate.java | 6 +-
.../exec/physical/impl/join/TestHashJoin.java | 26 +++++
.../src/test/resources/join/hj_exchanges.json | 96 ++++++++++++++++
7 files changed, 231 insertions(+), 75 deletions(-)
----------------------------------------------------------------------
http://git-wip-us.apache.org/repos/asf/incubator-drill/blob/5603a633/exec/java-exec/src/main/java/org/apache/drill/exec/physical/config/HashJoinPOP.java
----------------------------------------------------------------------
diff --git a/exec/java-exec/src/main/java/org/apache/drill/exec/physical/config/HashJoinPOP.java b/exec/java-exec/src/main/java/org/apache/drill/exec/physical/config/HashJoinPOP.java
index 0718bff..c3e74cf 100644
--- a/exec/java-exec/src/main/java/org/apache/drill/exec/physical/config/HashJoinPOP.java
+++ b/exec/java-exec/src/main/java/org/apache/drill/exec/physical/config/HashJoinPOP.java
@@ -51,7 +51,6 @@ public class HashJoinPOP extends AbstractBase {
private final PhysicalOperator right;
private final List<JoinCondition> conditions;
private final JoinRelType joinType;
- private final HashTableConfig htConfig;
@Override
public OperatorCost getCost() {
@@ -69,23 +68,6 @@ public class HashJoinPOP extends AbstractBase {
this.right = right;
this.conditions = conditions;
this.joinType = joinType;
-
- int conditionsSize = conditions.size();
-
- NamedExpression rightExpr[] = new NamedExpression[conditionsSize];
- NamedExpression leftExpr[] = new NamedExpression[conditionsSize];
-
- for (int i = 0; i < conditionsSize; i++) {
- rightExpr[i] = new NamedExpression(conditions.get(i).getRight(), new FieldReference("build_side_" + i ));
- leftExpr[i] = new NamedExpression(conditions.get(i).getLeft(), new FieldReference("probe_side_" + i));
-
- // Hash join only supports equality currently.
- assert conditions.get(i).getRelationship().equals("==");
- }
-
- this.htConfig = new HashTableConfig(HashTable.DEFAULT_INITIAL_CAPACITY,
- HashTable.DEFAULT_LOAD_FACTOR,
- rightExpr, leftExpr);
}
@Override
@@ -125,10 +107,6 @@ public class HashJoinPOP extends AbstractBase {
return conditions;
}
- public HashTableConfig getHtConfig() {
- return htConfig;
- }
-
public HashJoinPOP flipIfRight(){
if(joinType == JoinRelType.RIGHT){
List<JoinCondition> flippedConditions = Lists.newArrayList(conditions.size());
http://git-wip-us.apache.org/repos/asf/incubator-drill/blob/5603a633/exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/join/HashJoinBatch.java
----------------------------------------------------------------------
diff --git a/exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/join/HashJoinBatch.java b/exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/join/HashJoinBatch.java
index 7ada651..5f0cc94 100644
--- a/exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/join/HashJoinBatch.java
+++ b/exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/join/HashJoinBatch.java
@@ -17,6 +17,9 @@
*/
package org.apache.drill.exec.physical.impl.join;
+import org.apache.drill.common.expression.FieldReference;
+import org.apache.drill.common.logical.data.JoinCondition;
+import org.apache.drill.common.logical.data.NamedExpression;
import org.apache.drill.exec.record.*;
import org.eigenbase.rel.JoinRelType;
@@ -56,8 +59,8 @@ public class HashJoinBatch extends AbstractRecordBatch<HashJoinPOP> {
// Join type, INNER, LEFT, RIGHT or OUTER
private final JoinRelType joinType;
- // hash table configuration, created in HashJoinPOP
- private HashTableConfig htConfig;
+ // Join conditions
+ private final List<JoinCondition> conditions;
// Runtime generated class implementing HashJoinProbe interface
private HashJoinProbe hashJoinProbe = null;
@@ -112,6 +115,11 @@ public class HashJoinBatch extends AbstractRecordBatch<HashJoinPOP> {
"outgoing" /* write container */,
PROJECT_PROBE, PROJECT_PROBE);
+ // indicates if we have previously returned an output batch
+ boolean firstOutputBatch = true;
+
+ IterOutcome leftUpstream = IterOutcome.NONE;
+
@Override
public int getRecordCount() {
return outputRecords;
@@ -136,7 +144,7 @@ public class HashJoinBatch extends AbstractRecordBatch<HashJoinPOP> {
* as well, for the materialization to be successful. This batch will not be used
* till we complete the build phase.
*/
- left.next();
+ leftUpstream = left.next();
// Build the hash table, using the build side record batches.
executeBuildPhase();
@@ -166,7 +174,14 @@ public class HashJoinBatch extends AbstractRecordBatch<HashJoinPOP> {
v.getValueVector().getMutator().setValueCount(outputRecords);
}
- return IterOutcome.OK_NEW_SCHEMA;
+ // First output batch, return OK_NEW_SCHEMA
+ if (firstOutputBatch == true) {
+ firstOutputBatch = false;
+ return IterOutcome.OK_NEW_SCHEMA;
+ }
+
+ // Not the first output batch
+ return IterOutcome.OK;
}
// No more output records, clean up and return
@@ -183,12 +198,32 @@ public class HashJoinBatch extends AbstractRecordBatch<HashJoinPOP> {
public void setupHashTable() throws IOException, SchemaChangeException, ClassTransformationException {
- // Shouldn't be recreating the hash table, this should be done only once
- assert hashTable == null;
+ // Setup the hash table configuration object
+ int conditionsSize = conditions.size();
+
+ NamedExpression rightExpr[] = new NamedExpression[conditionsSize];
+ NamedExpression leftExpr[] = new NamedExpression[conditionsSize];
+
+ // Create named expressions from the conditions
+ for (int i = 0; i < conditionsSize; i++) {
+ rightExpr[i] = new NamedExpression(conditions.get(i).getRight(), new FieldReference("build_side_" + i ));
+ leftExpr[i] = new NamedExpression(conditions.get(i).getLeft(), new FieldReference("probe_side_" + i));
+
+ // Hash join only supports equality currently.
+ assert conditions.get(i).getRelationship().equals("==");
+ }
+
+ // Set the left named expression to be null if the probe batch is empty.
+ if (leftUpstream != IterOutcome.OK_NEW_SCHEMA && leftUpstream != IterOutcome.OK) {
+ leftExpr = null;
+ }
+
+ HashTableConfig htConfig = new HashTableConfig(HashTable.DEFAULT_INITIAL_CAPACITY, HashTable.DEFAULT_LOAD_FACTOR, rightExpr, leftExpr);
+
+ // Create the chained hash table
ChainedHashTable ht = new ChainedHashTable(htConfig, context, this.right, this.left, null);
hashTable = ht.createAndSetupHashTable(null);
-
}
public void executeBuildPhase() throws SchemaChangeException, ClassTransformationException, IOException {
@@ -198,8 +233,6 @@ public class HashJoinBatch extends AbstractRecordBatch<HashJoinPOP> {
boolean moreData = true;
- setupHashTable();
-
while (moreData) {
switch (rightUpstream) {
@@ -213,6 +246,7 @@ public class HashJoinBatch extends AbstractRecordBatch<HashJoinPOP> {
case OK_NEW_SCHEMA:
if (rightSchema == null) {
rightSchema = right.getSchema();
+ setupHashTable();
} else {
throw new SchemaChangeException("Hash join does not support schema changes");
}
@@ -277,22 +311,25 @@ public class HashJoinBatch extends AbstractRecordBatch<HashJoinPOP> {
JExpression buildIndex = JExpr.direct("buildIndex");
JExpression outIndex = JExpr.direct("outIndex");
g.rotateBlock();
- for(VectorWrapper<?> vv : hyperContainer) {
- // Add the vector to our output container
- ValueVector v = TypeHelper.getNewVector(vv.getField(), context.getAllocator());
- container.add(v);
- allocators.add(RemovingRecordBatch.getAllocator4(v));
+ if (hyperContainer != null) {
+ for(VectorWrapper<?> vv : hyperContainer) {
- JVar inVV = g.declareVectorValueSetupAndMember("buildBatch", new TypedFieldId(vv.getField().getType(), fieldId, true));
- JVar outVV = g.declareVectorValueSetupAndMember("outgoing", new TypedFieldId(vv.getField().getType(), fieldId, false));
+ // Add the vector to our output container
+ ValueVector v = TypeHelper.getNewVector(vv.getField(), context.getAllocator());
+ container.add(v);
+ allocators.add(RemovingRecordBatch.getAllocator4(v));
- g.getEvalBlock().add(outVV.invoke("copyFrom")
- .arg(buildIndex.band(JExpr.lit((int) Character.MAX_VALUE)))
- .arg(outIndex)
- .arg(inVV.component(buildIndex.shrz(JExpr.lit(16)))));
+ JVar inVV = g.declareVectorValueSetupAndMember("buildBatch", new TypedFieldId(vv.getField().getType(), fieldId, true));
+ JVar outVV = g.declareVectorValueSetupAndMember("outgoing", new TypedFieldId(vv.getField().getType(), fieldId, false));
- fieldId++;
+ g.getEvalBlock().add(outVV.invoke("copyFrom")
+ .arg(buildIndex.band(JExpr.lit((int) Character.MAX_VALUE)))
+ .arg(outIndex)
+ .arg(inVV.component(buildIndex.shrz(JExpr.lit(16)))));
+
+ fieldId++;
+ }
}
// Generate the code to project probe side records
@@ -301,23 +338,29 @@ public class HashJoinBatch extends AbstractRecordBatch<HashJoinPOP> {
int outputFieldId = fieldId;
fieldId = 0;
JExpression probeIndex = JExpr.direct("probeIndex");
- for (VectorWrapper<?> vv : left) {
+ int recordCount = 0;
- ValueVector v = TypeHelper.getNewVector(vv.getField(), context.getAllocator());
- container.add(v);
- allocators.add(RemovingRecordBatch.getAllocator4(v));
+ if (leftUpstream == IterOutcome.OK || leftUpstream == IterOutcome.OK_NEW_SCHEMA) {
+ for (VectorWrapper<?> vv : left) {
- JVar inVV = g.declareVectorValueSetupAndMember("probeBatch", new TypedFieldId(vv.getField().getType(), fieldId, false));
- JVar outVV = g.declareVectorValueSetupAndMember("outgoing", new TypedFieldId(vv.getField().getType(), outputFieldId, false));
+ ValueVector v = TypeHelper.getNewVector(vv.getField(), context.getAllocator());
+ container.add(v);
+ allocators.add(RemovingRecordBatch.getAllocator4(v));
- g.getEvalBlock().add(outVV.invoke("copyFrom").arg(probeIndex).arg(outIndex).arg(inVV));
+ JVar inVV = g.declareVectorValueSetupAndMember("probeBatch", new TypedFieldId(vv.getField().getType(), fieldId, false));
+ JVar outVV = g.declareVectorValueSetupAndMember("outgoing", new TypedFieldId(vv.getField().getType(), outputFieldId, false));
- fieldId++;
- outputFieldId++;
+ g.getEvalBlock().add(outVV.invoke("copyFrom").arg(probeIndex).arg(outIndex).arg(inVV));
+
+ fieldId++;
+ outputFieldId++;
+ }
+ recordCount = left.getRecordCount();
}
HashJoinProbe hj = context.getImplementationClass(cg);
- hj.setupHashJoinProbe(context, hyperContainer, left, this, hashTable, hjHelper, joinType);
+
+ hj.setupHashJoinProbe(context, hyperContainer, left, recordCount, this, hashTable, hjHelper, joinType);
return hj;
}
@@ -332,7 +375,7 @@ public class HashJoinBatch extends AbstractRecordBatch<HashJoinPOP> {
this.left = left;
this.right = right;
this.joinType = popConfig.getJoinType();
- this.htConfig = popConfig.getHtConfig();
+ this.conditions = popConfig.getConditions();
}
@Override
@@ -346,10 +389,14 @@ public class HashJoinBatch extends AbstractRecordBatch<HashJoinPOP> {
public void cleanup() {
left.cleanup();
right.cleanup();
- hyperContainer.clear();
hjHelper.clear();
container.clear();
- hashTable.clear();
+
+ // If we didn't receive any data, hyperContainer may be null, check before clearing
+ if (hyperContainer != null) {
+ hyperContainer.clear();
+ hashTable.clear();
+ }
super.cleanup();
}
}
http://git-wip-us.apache.org/repos/asf/incubator-drill/blob/5603a633/exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/join/HashJoinHelper.java
----------------------------------------------------------------------
diff --git a/exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/join/HashJoinHelper.java b/exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/join/HashJoinHelper.java
index e0098b1..0728ac9 100644
--- a/exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/join/HashJoinHelper.java
+++ b/exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/join/HashJoinHelper.java
@@ -187,25 +187,33 @@ public class HashJoinHelper {
SelectionVector4 startIndex = startIndices.get(batchIdx);
int linkIndex;
- // If its the first value for this key
+ // If head of the list is empty, insert current index at this position
if ((linkIndex = (startIndex.get(offsetIdx))) == INDEX_EMPTY) {
startIndex.set(offsetIdx, batchIndex, recordIndex);
} else {
- /* we already have encountered a record with the same key
- * use links to store this value
+ /* Head of this list is not empty, if the first link
+ * is empty insert there
*/
- SelectionVector4 link;
- do {
- //Traverse the links to get an empty slot to insert the current index
- batchIdx = linkIndex >>> SHIFT_SIZE;
- offsetIdx = linkIndex & Character.MAX_VALUE;
-
- // get the next link
- link = buildInfoList.get(batchIdx).getLinks();
- } while ((linkIndex = link.get(offsetIdx)) != INDEX_EMPTY);
-
- // We have the correct batchIdx and offset within the batch to store the next link
- link.set(offsetIdx, batchIndex, recordIndex);
+ batchIdx = linkIndex >>> SHIFT_SIZE;
+ offsetIdx = linkIndex & Character.MAX_VALUE;
+
+ SelectionVector4 link = buildInfoList.get(batchIdx).getLinks();
+ int firstLink = link.get(offsetIdx);
+
+ if (firstLink == INDEX_EMPTY) {
+ link.set(offsetIdx, batchIndex, recordIndex);
+ } else {
+ /* Insert the current value as the first link and
+ * make the current first link as its next
+ */
+ int firstLinkBatchIdx = firstLink >>> SHIFT_SIZE;
+ int firstLinkOffsetIDx = firstLink & Character.MAX_VALUE;
+
+ SelectionVector4 nextLink = buildInfoList.get(batchIndex).getLinks();
+ nextLink.set(recordIndex, firstLinkBatchIdx, firstLinkOffsetIDx);
+
+ link.set(offsetIdx, batchIndex, recordIndex);
+ }
}
}
http://git-wip-us.apache.org/repos/asf/incubator-drill/blob/5603a633/exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/join/HashJoinProbe.java
----------------------------------------------------------------------
diff --git a/exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/join/HashJoinProbe.java b/exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/join/HashJoinProbe.java
index c99f2a6..0ffdf52 100644
--- a/exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/join/HashJoinProbe.java
+++ b/exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/join/HashJoinProbe.java
@@ -48,7 +48,8 @@ public interface HashJoinProbe {
}
public abstract void setupHashJoinProbe(FragmentContext context, VectorContainer buildBatch, RecordBatch probeBatch,
- RecordBatch outgoing, HashTable hashTable, HashJoinHelper hjHelper, JoinRelType joinRelType);
+ int probeRecordCount, RecordBatch outgoing, HashTable hashTable, HashJoinHelper hjHelper,
+ JoinRelType joinRelType);
public abstract void doSetup(FragmentContext context, VectorContainer buildBatch, RecordBatch probeBatch, RecordBatch outgoing);
public abstract int probeAndProject() throws SchemaChangeException, ClassTransformationException, IOException;
public abstract void projectBuildRecord(int buildIndex, int outIndex);
http://git-wip-us.apache.org/repos/asf/incubator-drill/blob/5603a633/exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/join/HashJoinProbeTemplate.java
----------------------------------------------------------------------
diff --git a/exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/join/HashJoinProbeTemplate.java b/exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/join/HashJoinProbeTemplate.java
index cc1a257..3d6f4d6 100644
--- a/exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/join/HashJoinProbeTemplate.java
+++ b/exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/join/HashJoinProbeTemplate.java
@@ -80,12 +80,12 @@ public abstract class HashJoinProbeTemplate implements HashJoinProbe {
@Override
public void setupHashJoinProbe(FragmentContext context, VectorContainer buildBatch, RecordBatch probeBatch,
- RecordBatch outgoing, HashTable hashTable, HashJoinHelper hjHelper,
- JoinRelType joinRelType) {
+ int probeRecordCount, RecordBatch outgoing, HashTable hashTable,
+ HashJoinHelper hjHelper, JoinRelType joinRelType) {
this.probeBatch = probeBatch;
this.joinType = joinRelType;
- this.recordsToProcess = probeBatch.getRecordCount();
+ this.recordsToProcess = probeRecordCount;
this.hashTable = hashTable;
this.hjHelper = hjHelper;
http://git-wip-us.apache.org/repos/asf/incubator-drill/blob/5603a633/exec/java-exec/src/test/java/org/apache/drill/exec/physical/impl/join/TestHashJoin.java
----------------------------------------------------------------------
diff --git a/exec/java-exec/src/test/java/org/apache/drill/exec/physical/impl/join/TestHashJoin.java b/exec/java-exec/src/test/java/org/apache/drill/exec/physical/impl/join/TestHashJoin.java
index ba067e2..f98015b 100644
--- a/exec/java-exec/src/test/java/org/apache/drill/exec/physical/impl/join/TestHashJoin.java
+++ b/exec/java-exec/src/test/java/org/apache/drill/exec/physical/impl/join/TestHashJoin.java
@@ -180,6 +180,32 @@ public class TestHashJoin extends PopUnitTestBase{
}
@Test
+ public void hjWithExchange(@Injectable final DrillbitContext bitContext,
+ @Injectable UserServer.UserClientConnection connection) throws Throwable {
+
+ // Function checks for casting from Float, Double to Decimal data types
+ try (RemoteServiceSet serviceSet = RemoteServiceSet.getLocalServiceSet();
+ Drillbit bit = new Drillbit(CONFIG, serviceSet);
+ DrillClient client = new DrillClient(CONFIG, serviceSet.getCoordinator())) {
+
+ // run query.
+ bit.run();
+ client.connect();
+ List<QueryResultBatch> results = client.runQuery(UserProtos.QueryType.PHYSICAL,
+ Files.toString(FileUtils.getResourceAsFile("/join/hj_exchanges.json"), Charsets.UTF_8));
+
+ int count = 0;
+ for(QueryResultBatch b : results) {
+ if (b.getHeader().getRowCount() != 0)
+ count += b.getHeader().getRowCount();
+ }
+
+ System.out.println("Total records: " + count);
+ assertEquals(25, count);
+ }
+ }
+
+ @Test
public void multipleConditionJoin(@Injectable final DrillbitContext bitContext,
@Injectable UserServer.UserClientConnection connection) throws Throwable {
http://git-wip-us.apache.org/repos/asf/incubator-drill/blob/5603a633/exec/java-exec/src/test/resources/join/hj_exchanges.json
----------------------------------------------------------------------
diff --git a/exec/java-exec/src/test/resources/join/hj_exchanges.json b/exec/java-exec/src/test/resources/join/hj_exchanges.json
new file mode 100644
index 0000000..2ad1cb4
--- /dev/null
+++ b/exec/java-exec/src/test/resources/join/hj_exchanges.json
@@ -0,0 +1,96 @@
+{
+ "head" : {
+ "version" : 1,
+ "generator" : {
+ "type" : "DefaultSqlHandler",
+ "info" : ""
+ },
+ "type" : "APACHE_DRILL_PHYSICAL",
+ "resultMode" : "EXEC"
+ },
+ "graph" : [ {
+ "pop" : "parquet-scan",
+ "@id" : 1,
+ "entries" : [ {
+ "path" : "/tpch/region.parquet"
+ } ],
+ "storage" : {
+ "type" : "file",
+ "connection" : "classpath:///",
+ "workspaces" : {
+ "default" : "/",
+ "home" : "/"
+ },
+ "formats" : null
+ },
+ "format" : {
+ "type" : "parquet"
+ }
+ }, {
+ "pop" : "hash-to-random-exchange",
+ "@id" : 2,
+ "child" : 1,
+ "expr" : "hash(`R_REGIONKEY`) "
+ }, {
+ "pop" : "parquet-scan",
+ "@id" : 3,
+ "entries" : [ {
+ "path" : "/tpch/nation.parquet"
+ } ],
+ "storage" : {
+ "type" : "file",
+ "connection" : "classpath:///",
+ "workspaces" : {
+ "default" : "/",
+ "home" : "/"
+ },
+ "formats" : null
+ },
+ "format" : {
+ "type" : "parquet"
+ }
+ }, {
+ "pop" : "hash-to-random-exchange",
+ "@id" : 4,
+ "child" : 3,
+ "expr" : "hash(`N_REGIONKEY`) "
+ }, {
+ "pop" : "project",
+ "@id" : 5,
+ "exprs" : [ {
+ "ref" : "`*0`",
+ "expr" : "`*`"
+ }, {
+ "ref" : "`N_REGIONKEY`",
+ "expr" : "`N_REGIONKEY`"
+ } ],
+ "child" : 4
+ }, {
+ "pop" : "hash-join",
+ "@id" : 6,
+ "left" : 2,
+ "right" : 5,
+ "conditions" : [ {
+ "relationship" : "==",
+ "left" : "`R_REGIONKEY`",
+ "right" : "`N_REGIONKEY`"
+ } ],
+ "joinType" : "INNER"
+ }, {
+ "pop" : "project",
+ "@id" : 9,
+ "exprs" : [ {
+ "ref" : "`R_REGIONKEY`",
+ "expr" : "`R_REGIONKEY`"
+ } ],
+ "child" : 6
+ }, {
+ "pop" : "union-exchange",
+ "@id" : 10,
+ "child" : 9
+ }, {
+ "pop" : "screen",
+ "@id" : 11,
+ "child" : 10
+ } ]
+}