[GitHub] [iceberg] szehon-ho commented on a diff in pull request #7175: Core, Spark 3.3: Add FileRewriter API

["szehon-ho (via GitHub)" <gi...@apache.org>]

szehon-ho commented on code in PR #7175:
URL: https://github.com/apache/iceberg/pull/7175#discussion_r1160954691


##########
core/src/main/java/org/apache/iceberg/actions/FileRewriter.java:
##########
@@ -0,0 +1,81 @@
+/*
+ * 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.iceberg.actions;
+
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import org.apache.iceberg.ContentFile;
+import org.apache.iceberg.ContentScanTask;
+
+/**
+ * A class for rewriting content files.
+ *
+ * @param <T> the Java type of tasks to read content files
+ * @param <F> the Java type of content files
+ */
+public interface FileRewriter<T extends ContentScanTask<F>, F extends ContentFile<F>> {
+  /** Returns a description for this rewriter. */
+  default String description() {
+    return getClass().getName();
+  }
+
+  /**
+   * Returns a set of supported options for this rewriter. This is an allowed-list and any options
+   * not specified here will be rejected at runtime.
+   *
+   * @return returns a set of supported options

Review Comment:
   Nit: extra "returns"



##########
core/src/main/java/org/apache/iceberg/actions/SizeBasedDataRewriter.java:
##########
@@ -0,0 +1,110 @@
+/*
+ * 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.iceberg.actions;
+
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.stream.Collectors;
+import org.apache.iceberg.DataFile;
+import org.apache.iceberg.FileScanTask;
+import org.apache.iceberg.Table;
+import org.apache.iceberg.TableProperties;
+import org.apache.iceberg.relocated.com.google.common.base.Preconditions;
+import org.apache.iceberg.relocated.com.google.common.collect.ImmutableSet;
+import org.apache.iceberg.relocated.com.google.common.collect.Iterables;
+import org.apache.iceberg.util.PropertyUtil;
+
+public abstract class SizeBasedDataRewriter extends SizeBasedFileRewriter<FileScanTask, DataFile> {
+
+  /**
+   * The minimum number of deletes that needs to be associated with a data file for it to be
+   * considered for rewriting. If a data file has this number of deletes or more, it will be
+   * rewritten regardless of its file size determined by {@link #MIN_FILE_SIZE_BYTES} and {@link
+   * #MAX_FILE_SIZE_BYTES}. If a file group contains a file that satisfies this condition, the file
+   * group will be rewritten regardless of the number of files in the file group determined by
+   * {@link #MIN_INPUT_FILES}
+   *
+   * <p>Defaults to Integer.MAX_VALUE, which means this feature is not enabled by default.
+   */
+  public static final String DELETE_FILE_THRESHOLD = "delete-file-threshold";
+
+  public static final int DELETE_FILE_THRESHOLD_DEFAULT = Integer.MAX_VALUE;
+
+  private int deleteFileThreshold;
+
+  protected SizeBasedDataRewriter(Table table) {
+    super(table);
+  }
+
+  @Override
+  public Set<String> validOptions() {
+    return ImmutableSet.<String>builder()
+        .addAll(super.validOptions())
+        .add(DELETE_FILE_THRESHOLD)
+        .build();
+  }
+
+  @Override
+  public void init(Map<String, String> options) {
+    super.init(options);
+    this.deleteFileThreshold = deleteFileThreshold(options);
+  }
+
+  @Override
+  protected Iterable<FileScanTask> doSelectFiles(Iterable<FileScanTask> tasks) {
+    return Iterables.filter(tasks, task -> hasSuboptimalSize(task) || hasTooManyDeletes(task));
+  }
+
+  private boolean hasTooManyDeletes(FileScanTask task) {

Review Comment:
   Remove 'has' to just 'tooManyDeletes' ?



##########
core/src/main/java/org/apache/iceberg/actions/SizeBasedFileRewriter.java:
##########
@@ -0,0 +1,320 @@
+/*
+ * 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.iceberg.actions;
+
+import java.math.RoundingMode;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import org.apache.iceberg.ContentFile;
+import org.apache.iceberg.ContentScanTask;
+import org.apache.iceberg.Table;
+import org.apache.iceberg.relocated.com.google.common.base.Preconditions;
+import org.apache.iceberg.relocated.com.google.common.collect.ImmutableSet;
+import org.apache.iceberg.relocated.com.google.common.collect.Maps;
+import org.apache.iceberg.relocated.com.google.common.math.LongMath;
+import org.apache.iceberg.util.BinPacking;
+import org.apache.iceberg.util.PropertyUtil;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * A file rewriter that determines which files to rewrite based on their size.
+ *
+ * <p>If files are smaller than the {@link #MIN_FILE_SIZE_BYTES} threshold or larger than the {@link
+ * #MAX_FILE_SIZE_BYTES} threshold, they are considered targets for being rewritten.
+ *
+ * <p>Once selected, files are grouped based on the {@link BinPacking bin-packing algorithm} into
+ * groups of no more than {@link #MAX_FILE_GROUP_SIZE_BYTES}. Groups will be actually rewritten if
+ * they contain more than {@link #MIN_INPUT_FILES} or if they would produce at least one file of
+ * {@link #TARGET_FILE_SIZE_BYTES}.
+ *
+ * <p>Note that implementations may add extra conditions for selecting files or filtering groups.
+ */
+abstract class SizeBasedFileRewriter<T extends ContentScanTask<F>, F extends ContentFile<F>>
+    implements FileRewriter<T, F> {
+
+  private static final Logger LOG = LoggerFactory.getLogger(SizeBasedFileRewriter.class);
+
+  /** The target output file size that this file rewriter will attempt to generate. */
+  public static final String TARGET_FILE_SIZE_BYTES = "target-file-size-bytes";
+
+  /**
+   * Adjusts files which will be considered for rewriting. Files smaller than this value will be

Review Comment:
   The word 'adjusts' seems strange here.  (file is not changed?)   
   
   Also 'functions independently' seems not clear.  Can we clarify, ex : 
   
   Any file with size under this threshold will be re-written, regardless of ...
   
   Also, one thought, as here we mention regardless of "MAX_FILE_SIZE_BYTES".  Does it make sense to just say "regardless of any other criteria", as there is also the question of whether we need to check tooManyDeletes as well.



##########
core/src/main/java/org/apache/iceberg/actions/SizeBasedFileRewriter.java:
##########
@@ -0,0 +1,320 @@
+/*
+ * 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.iceberg.actions;
+
+import java.math.RoundingMode;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import org.apache.iceberg.ContentFile;
+import org.apache.iceberg.ContentScanTask;
+import org.apache.iceberg.Table;
+import org.apache.iceberg.relocated.com.google.common.base.Preconditions;
+import org.apache.iceberg.relocated.com.google.common.collect.ImmutableSet;
+import org.apache.iceberg.relocated.com.google.common.collect.Maps;
+import org.apache.iceberg.relocated.com.google.common.math.LongMath;
+import org.apache.iceberg.util.BinPacking;
+import org.apache.iceberg.util.PropertyUtil;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * A file rewriter that determines which files to rewrite based on their size.
+ *
+ * <p>If files are smaller than the {@link #MIN_FILE_SIZE_BYTES} threshold or larger than the {@link
+ * #MAX_FILE_SIZE_BYTES} threshold, they are considered targets for being rewritten.
+ *
+ * <p>Once selected, files are grouped based on the {@link BinPacking bin-packing algorithm} into
+ * groups of no more than {@link #MAX_FILE_GROUP_SIZE_BYTES}. Groups will be actually rewritten if
+ * they contain more than {@link #MIN_INPUT_FILES} or if they would produce at least one file of
+ * {@link #TARGET_FILE_SIZE_BYTES}.
+ *
+ * <p>Note that implementations may add extra conditions for selecting files or filtering groups.
+ */
+abstract class SizeBasedFileRewriter<T extends ContentScanTask<F>, F extends ContentFile<F>>
+    implements FileRewriter<T, F> {
+
+  private static final Logger LOG = LoggerFactory.getLogger(SizeBasedFileRewriter.class);
+
+  /** The target output file size that this file rewriter will attempt to generate. */
+  public static final String TARGET_FILE_SIZE_BYTES = "target-file-size-bytes";
+
+  /**
+   * Adjusts files which will be considered for rewriting. Files smaller than this value will be
+   * considered for rewriting. This functions independently of {@link #MAX_FILE_SIZE_BYTES}.
+   *
+   * <p>Defaults to 75% of the target file size.
+   */
+  public static final String MIN_FILE_SIZE_BYTES = "min-file-size-bytes";
+
+  public static final double MIN_FILE_SIZE_DEFAULT_RATIO = 0.75;
+
+  /**
+   * Adjusts files which will be considered for rewriting. Files larger than this value will be
+   * considered for rewriting. This functions independently of {@link #MIN_FILE_SIZE_BYTES}.
+   *
+   * <p>Defaults to 180% of the target file size.
+   */
+  public static final String MAX_FILE_SIZE_BYTES = "max-file-size-bytes";
+
+  public static final double MAX_FILE_SIZE_DEFAULT_RATIO = 1.80;
+
+  /**
+   * The minimum number of files that need to be in a file group for it to be considered for
+   * compaction if the total size of that group is less than the target file size. This can also be

Review Comment:
   Is it true:
   
   ```
     private boolean shouldRewrite(List<FileScanTask> group) {
       return hasEnoughInputFiles(group)
           || hasEnoughData(group)
           || hasTooMuchData(group)
           || anyTaskHasTooManyDeletes(group);
   ```
   
   Shouldn't it be "any file group exceeding this number of files will be rewritten regardless of other criteria"



##########
core/src/main/java/org/apache/iceberg/actions/SizeBasedFileRewriter.java:
##########
@@ -0,0 +1,320 @@
+/*
+ * 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.iceberg.actions;
+
+import java.math.RoundingMode;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import org.apache.iceberg.ContentFile;
+import org.apache.iceberg.ContentScanTask;
+import org.apache.iceberg.Table;
+import org.apache.iceberg.relocated.com.google.common.base.Preconditions;
+import org.apache.iceberg.relocated.com.google.common.collect.ImmutableSet;
+import org.apache.iceberg.relocated.com.google.common.collect.Maps;
+import org.apache.iceberg.relocated.com.google.common.math.LongMath;
+import org.apache.iceberg.util.BinPacking;
+import org.apache.iceberg.util.PropertyUtil;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * A file rewriter that determines which files to rewrite based on their size.
+ *
+ * <p>If files are smaller than the {@link #MIN_FILE_SIZE_BYTES} threshold or larger than the {@link
+ * #MAX_FILE_SIZE_BYTES} threshold, they are considered targets for being rewritten.
+ *
+ * <p>Once selected, files are grouped based on the {@link BinPacking bin-packing algorithm} into
+ * groups of no more than {@link #MAX_FILE_GROUP_SIZE_BYTES}. Groups will be actually rewritten if
+ * they contain more than {@link #MIN_INPUT_FILES} or if they would produce at least one file of
+ * {@link #TARGET_FILE_SIZE_BYTES}.
+ *
+ * <p>Note that implementations may add extra conditions for selecting files or filtering groups.
+ */
+abstract class SizeBasedFileRewriter<T extends ContentScanTask<F>, F extends ContentFile<F>>
+    implements FileRewriter<T, F> {
+
+  private static final Logger LOG = LoggerFactory.getLogger(SizeBasedFileRewriter.class);
+
+  /** The target output file size that this file rewriter will attempt to generate. */
+  public static final String TARGET_FILE_SIZE_BYTES = "target-file-size-bytes";
+
+  /**
+   * Adjusts files which will be considered for rewriting. Files smaller than this value will be
+   * considered for rewriting. This functions independently of {@link #MAX_FILE_SIZE_BYTES}.
+   *
+   * <p>Defaults to 75% of the target file size.
+   */
+  public static final String MIN_FILE_SIZE_BYTES = "min-file-size-bytes";
+
+  public static final double MIN_FILE_SIZE_DEFAULT_RATIO = 0.75;
+
+  /**
+   * Adjusts files which will be considered for rewriting. Files larger than this value will be
+   * considered for rewriting. This functions independently of {@link #MIN_FILE_SIZE_BYTES}.
+   *
+   * <p>Defaults to 180% of the target file size.
+   */
+  public static final String MAX_FILE_SIZE_BYTES = "max-file-size-bytes";
+
+  public static final double MAX_FILE_SIZE_DEFAULT_RATIO = 1.80;
+
+  /**
+   * The minimum number of files that need to be in a file group for it to be considered for
+   * compaction if the total size of that group is less than the target file size. This can also be
+   * thought of as the maximum number of wrongly sized files that could remain in a partition after
+   * rewriting.
+   */
+  public static final String MIN_INPUT_FILES = "min-input-files";
+
+  public static final int MIN_INPUT_FILES_DEFAULT = 5;
+
+  /** Overrides other options and forces rewriting of all files. */
+  public static final String REWRITE_ALL = "rewrite-all";
+
+  public static final boolean REWRITE_ALL_DEFAULT = false;
+
+  /**
+   * The entire rewrite operation is broken down into pieces based on partitioning and within
+   * partitions based on size into groups. These subunits of the rewrite are referred to as file
+   * groups. This option controls the largest amount of data that should be rewritten in a single
+   * group. It helps with breaking down the rewriting of very large partitions which may not be
+   * rewritable otherwise due to the resource constraints of the cluster. For example, a sort-based
+   * rewrite may not scale to TB sized partitions, those partitions need to be worked on in small
+   * subsections to avoid exhaustion of resources.
+   *
+   * <p>When grouping files, the file rewriter will use this value to limit the files which will be
+   * included in a single file group. A group will be processed by a single framework "action". For
+   * example, in Spark this means that each group would be rewritten in its own Spark job. A group
+   * will never contain files for multiple output partitions.
+   */
+  public static final String MAX_FILE_GROUP_SIZE_BYTES = "max-file-group-size-bytes";
+
+  public static final long MAX_FILE_GROUP_SIZE_BYTES_DEFAULT = 100L * 1024 * 1024 * 1024; // 100 GB
+
+  private final Table table;
+  private long targetFileSize;
+  private long minFileSize;
+  private long maxFileSize;
+  private int minInputFiles;
+  private boolean rewriteAll;
+  private long maxGroupSize;
+
+  protected SizeBasedFileRewriter(Table table) {
+    this.table = table;
+  }
+
+  protected abstract long defaultTargetFileSize();
+
+  protected abstract Iterable<T> doSelectFiles(Iterable<T> tasks);
+
+  protected abstract List<List<T>> filterFileGroups(List<List<T>> groups);
+
+  protected Table table() {
+    return table;
+  }
+
+  @Override
+  public Set<String> validOptions() {
+    return ImmutableSet.of(
+        TARGET_FILE_SIZE_BYTES,
+        MIN_FILE_SIZE_BYTES,
+        MAX_FILE_SIZE_BYTES,
+        MIN_INPUT_FILES,
+        REWRITE_ALL,
+        MAX_FILE_GROUP_SIZE_BYTES);
+  }
+
+  @Override
+  public void init(Map<String, String> options) {
+    Map<String, Long> sizeThresholds = sizeThresholds(options);
+    this.targetFileSize = sizeThresholds.get(TARGET_FILE_SIZE_BYTES);
+    this.minFileSize = sizeThresholds.get(MIN_FILE_SIZE_BYTES);
+    this.maxFileSize = sizeThresholds.get(MAX_FILE_SIZE_BYTES);
+
+    this.minInputFiles = minInputFiles(options);
+    this.rewriteAll = rewriteAll(options);
+    this.maxGroupSize = maxGroupSize(options);
+
+    if (rewriteAll) {
+      LOG.info("Configured to rewrite all provided files in table {}", table.name());
+    }
+  }
+
+  @Override
+  public Iterable<T> selectFiles(Iterable<T> tasks) {
+    return rewriteAll ? tasks : doSelectFiles(tasks);
+  }
+
+  protected boolean hasSuboptimalSize(T task) {
+    return task.length() < minFileSize || task.length() > maxFileSize;
+  }
+
+  @Override
+  public Iterable<List<T>> planFileGroups(Iterable<T> tasks) {
+    BinPacking.ListPacker<T> packer = new BinPacking.ListPacker<>(maxGroupSize, 1, false);
+    List<List<T>> groups = packer.pack(tasks, ContentScanTask::length);
+    return rewriteAll ? groups : filterFileGroups(groups);
+  }
+
+  protected boolean hasEnoughInputFiles(List<T> group) {
+    return group.size() > 1 && group.size() >= minInputFiles;
+  }
+
+  protected boolean hasEnoughData(List<T> group) {
+    return group.size() > 1 && inputSize(group) > targetFileSize;
+  }
+
+  protected boolean hasTooMuchData(List<T> group) {
+    return inputSize(group) > maxFileSize;
+  }
+
+  protected long inputSize(List<T> group) {
+    return group.stream().mapToLong(ContentScanTask::length).sum();
+  }
+
+  /**
+   * Determines the preferable number of output files when rewriting a particular file group.
+   *
+   * <p>If the rewriter is handling 10.1 GB of data with a target file size of 1 GB, it could
+   * produce 11 files, one of which would only have 0.1 GB. This would most likely be less
+   * preferable to 10 files with 1.01 GB each. So this method decides whether to round up or round
+   * down based on what the estimated average file size will be if the remainder (0.1 GB) is
+   * distributed amongst other files. If the new average file size is no more than 10% greater than
+   * the target file size, then this method will round down when determining the number of output
+   * files. Otherwise, the remainder will be written into a separate file.
+   *
+   * @param inputSize a total input size for a file group
+   * @return the number of files this rewriter should create
+   */
+  protected long numOutputFiles(long inputSize) {
+    if (inputSize < targetFileSize) {
+      return 1;
+    }
+
+    long numFilesWithRemainder = LongMath.divide(inputSize, targetFileSize, RoundingMode.CEILING);
+    long numFilesWithoutRemainder = LongMath.divide(inputSize, targetFileSize, RoundingMode.FLOOR);
+    long avgFileSizeWithoutRemainder = inputSize / numFilesWithoutRemainder;
+
+    if (LongMath.mod(inputSize, targetFileSize) > minFileSize) {
+      // the remainder file is of a valid size for this rewrite so keep it
+      return numFilesWithRemainder;
+
+    } else if (avgFileSizeWithoutRemainder < Math.min(1.1 * targetFileSize, writeMaxFileSize())) {
+      // if the reminder is distributed amongst other files,
+      // the average file size will be no more than 10% bigger than the target file size
+      // so round down and distribute remainder amongst other files
+      return numFilesWithoutRemainder;
+
+    } else {
+      // keep the remainder file as it is not OK to distribute it amongst other files
+      return numFilesWithRemainder;
+    }
+  }
+
+  /**
+   * Estimates a larger max target file size than the target size used in task creation to avoid
+   * tasks which are predicted to have a certain size, but exceed that target size when serde is
+   * complete creating tiny remainder files.

Review Comment:
   Hard to read, a comma may help:
   
   "when serde is complete, creating tiny remainder files"



##########
core/src/main/java/org/apache/iceberg/actions/SizeBasedFileRewriter.java:
##########
@@ -0,0 +1,320 @@
+/*
+ * 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.iceberg.actions;
+
+import java.math.RoundingMode;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import org.apache.iceberg.ContentFile;
+import org.apache.iceberg.ContentScanTask;
+import org.apache.iceberg.Table;
+import org.apache.iceberg.relocated.com.google.common.base.Preconditions;
+import org.apache.iceberg.relocated.com.google.common.collect.ImmutableSet;
+import org.apache.iceberg.relocated.com.google.common.collect.Maps;
+import org.apache.iceberg.relocated.com.google.common.math.LongMath;
+import org.apache.iceberg.util.BinPacking;
+import org.apache.iceberg.util.PropertyUtil;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * A file rewriter that determines which files to rewrite based on their size.
+ *
+ * <p>If files are smaller than the {@link #MIN_FILE_SIZE_BYTES} threshold or larger than the {@link
+ * #MAX_FILE_SIZE_BYTES} threshold, they are considered targets for being rewritten.
+ *
+ * <p>Once selected, files are grouped based on the {@link BinPacking bin-packing algorithm} into
+ * groups of no more than {@link #MAX_FILE_GROUP_SIZE_BYTES}. Groups will be actually rewritten if
+ * they contain more than {@link #MIN_INPUT_FILES} or if they would produce at least one file of
+ * {@link #TARGET_FILE_SIZE_BYTES}.
+ *
+ * <p>Note that implementations may add extra conditions for selecting files or filtering groups.
+ */
+abstract class SizeBasedFileRewriter<T extends ContentScanTask<F>, F extends ContentFile<F>>
+    implements FileRewriter<T, F> {
+
+  private static final Logger LOG = LoggerFactory.getLogger(SizeBasedFileRewriter.class);
+
+  /** The target output file size that this file rewriter will attempt to generate. */
+  public static final String TARGET_FILE_SIZE_BYTES = "target-file-size-bytes";
+
+  /**
+   * Adjusts files which will be considered for rewriting. Files smaller than this value will be
+   * considered for rewriting. This functions independently of {@link #MAX_FILE_SIZE_BYTES}.
+   *
+   * <p>Defaults to 75% of the target file size.
+   */
+  public static final String MIN_FILE_SIZE_BYTES = "min-file-size-bytes";
+
+  public static final double MIN_FILE_SIZE_DEFAULT_RATIO = 0.75;
+
+  /**
+   * Adjusts files which will be considered for rewriting. Files larger than this value will be
+   * considered for rewriting. This functions independently of {@link #MIN_FILE_SIZE_BYTES}.
+   *
+   * <p>Defaults to 180% of the target file size.
+   */
+  public static final String MAX_FILE_SIZE_BYTES = "max-file-size-bytes";
+
+  public static final double MAX_FILE_SIZE_DEFAULT_RATIO = 1.80;
+
+  /**
+   * The minimum number of files that need to be in a file group for it to be considered for
+   * compaction if the total size of that group is less than the target file size. This can also be
+   * thought of as the maximum number of wrongly sized files that could remain in a partition after
+   * rewriting.
+   */
+  public static final String MIN_INPUT_FILES = "min-input-files";
+
+  public static final int MIN_INPUT_FILES_DEFAULT = 5;
+
+  /** Overrides other options and forces rewriting of all files. */
+  public static final String REWRITE_ALL = "rewrite-all";
+
+  public static final boolean REWRITE_ALL_DEFAULT = false;
+
+  /**
+   * The entire rewrite operation is broken down into pieces based on partitioning and within
+   * partitions based on size into groups. These subunits of the rewrite are referred to as file
+   * groups. This option controls the largest amount of data that should be rewritten in a single
+   * group. It helps with breaking down the rewriting of very large partitions which may not be
+   * rewritable otherwise due to the resource constraints of the cluster. For example, a sort-based
+   * rewrite may not scale to TB sized partitions, those partitions need to be worked on in small
+   * subsections to avoid exhaustion of resources.
+   *
+   * <p>When grouping files, the file rewriter will use this value to limit the files which will be
+   * included in a single file group. A group will be processed by a single framework "action". For
+   * example, in Spark this means that each group would be rewritten in its own Spark job. A group
+   * will never contain files for multiple output partitions.
+   */
+  public static final String MAX_FILE_GROUP_SIZE_BYTES = "max-file-group-size-bytes";
+
+  public static final long MAX_FILE_GROUP_SIZE_BYTES_DEFAULT = 100L * 1024 * 1024 * 1024; // 100 GB
+
+  private final Table table;
+  private long targetFileSize;
+  private long minFileSize;
+  private long maxFileSize;
+  private int minInputFiles;
+  private boolean rewriteAll;
+  private long maxGroupSize;
+
+  protected SizeBasedFileRewriter(Table table) {
+    this.table = table;
+  }
+
+  protected abstract long defaultTargetFileSize();
+
+  protected abstract Iterable<T> doSelectFiles(Iterable<T> tasks);
+
+  protected abstract List<List<T>> filterFileGroups(List<List<T>> groups);
+
+  protected Table table() {
+    return table;
+  }
+
+  @Override
+  public Set<String> validOptions() {
+    return ImmutableSet.of(
+        TARGET_FILE_SIZE_BYTES,
+        MIN_FILE_SIZE_BYTES,
+        MAX_FILE_SIZE_BYTES,
+        MIN_INPUT_FILES,
+        REWRITE_ALL,
+        MAX_FILE_GROUP_SIZE_BYTES);
+  }
+
+  @Override
+  public void init(Map<String, String> options) {
+    Map<String, Long> sizeThresholds = sizeThresholds(options);
+    this.targetFileSize = sizeThresholds.get(TARGET_FILE_SIZE_BYTES);
+    this.minFileSize = sizeThresholds.get(MIN_FILE_SIZE_BYTES);
+    this.maxFileSize = sizeThresholds.get(MAX_FILE_SIZE_BYTES);
+
+    this.minInputFiles = minInputFiles(options);
+    this.rewriteAll = rewriteAll(options);
+    this.maxGroupSize = maxGroupSize(options);
+
+    if (rewriteAll) {
+      LOG.info("Configured to rewrite all provided files in table {}", table.name());
+    }
+  }
+
+  @Override
+  public Iterable<T> selectFiles(Iterable<T> tasks) {
+    return rewriteAll ? tasks : doSelectFiles(tasks);
+  }
+
+  protected boolean hasSuboptimalSize(T task) {
+    return task.length() < minFileSize || task.length() > maxFileSize;
+  }
+
+  @Override
+  public Iterable<List<T>> planFileGroups(Iterable<T> tasks) {
+    BinPacking.ListPacker<T> packer = new BinPacking.ListPacker<>(maxGroupSize, 1, false);
+    List<List<T>> groups = packer.pack(tasks, ContentScanTask::length);
+    return rewriteAll ? groups : filterFileGroups(groups);
+  }
+
+  protected boolean hasEnoughInputFiles(List<T> group) {
+    return group.size() > 1 && group.size() >= minInputFiles;
+  }
+
+  protected boolean hasEnoughData(List<T> group) {
+    return group.size() > 1 && inputSize(group) > targetFileSize;
+  }
+
+  protected boolean hasTooMuchData(List<T> group) {
+    return inputSize(group) > maxFileSize;
+  }
+
+  protected long inputSize(List<T> group) {
+    return group.stream().mapToLong(ContentScanTask::length).sum();
+  }
+
+  /**
+   * Determines the preferable number of output files when rewriting a particular file group.
+   *
+   * <p>If the rewriter is handling 10.1 GB of data with a target file size of 1 GB, it could
+   * produce 11 files, one of which would only have 0.1 GB. This would most likely be less
+   * preferable to 10 files with 1.01 GB each. So this method decides whether to round up or round
+   * down based on what the estimated average file size will be if the remainder (0.1 GB) is
+   * distributed amongst other files. If the new average file size is no more than 10% greater than
+   * the target file size, then this method will round down when determining the number of output
+   * files. Otherwise, the remainder will be written into a separate file.
+   *
+   * @param inputSize a total input size for a file group
+   * @return the number of files this rewriter should create
+   */
+  protected long numOutputFiles(long inputSize) {
+    if (inputSize < targetFileSize) {
+      return 1;
+    }
+
+    long numFilesWithRemainder = LongMath.divide(inputSize, targetFileSize, RoundingMode.CEILING);
+    long numFilesWithoutRemainder = LongMath.divide(inputSize, targetFileSize, RoundingMode.FLOOR);
+    long avgFileSizeWithoutRemainder = inputSize / numFilesWithoutRemainder;
+
+    if (LongMath.mod(inputSize, targetFileSize) > minFileSize) {
+      // the remainder file is of a valid size for this rewrite so keep it
+      return numFilesWithRemainder;
+
+    } else if (avgFileSizeWithoutRemainder < Math.min(1.1 * targetFileSize, writeMaxFileSize())) {
+      // if the reminder is distributed amongst other files,
+      // the average file size will be no more than 10% bigger than the target file size
+      // so round down and distribute remainder amongst other files
+      return numFilesWithoutRemainder;
+
+    } else {
+      // keep the remainder file as it is not OK to distribute it amongst other files
+      return numFilesWithRemainder;
+    }
+  }
+
+  /**
+   * Estimates a larger max target file size than the target size used in task creation to avoid
+   * tasks which are predicted to have a certain size, but exceed that target size when serde is
+   * complete creating tiny remainder files.
+   *
+   * <p>While we create tasks that should all be smaller than our target size, there is a chance
+   * that the actual data will end up being larger than our target size due to various factors of
+   * compression, serialization and other factors outside our control. If this occurs, instead of
+   * making a single file that is close in size to our target, we would end up producing one file of
+   * the target size, and then a small extra file with the remaining data. For example, if our
+   * target is 512 MB, we may generate a rewrite task that should be 500 MB. When we write the data
+   * we may find we actually have to write out 530 MB. If we use the target size while writing we

Review Comment:
   nit: comma before we
   
   "while writing, we..."



##########
core/src/main/java/org/apache/iceberg/actions/FileRewriter.java:
##########
@@ -0,0 +1,81 @@
+/*
+ * 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.iceberg.actions;
+
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import org.apache.iceberg.ContentFile;
+import org.apache.iceberg.ContentScanTask;
+
+/**
+ * A class for rewriting content files.
+ *
+ * @param <T> the Java type of tasks to read content files
+ * @param <F> the Java type of content files
+ */
+public interface FileRewriter<T extends ContentScanTask<F>, F extends ContentFile<F>> {
+  /** Returns a description for this rewriter. */

Review Comment:
   Nit: newline before this class



##########
core/src/main/java/org/apache/iceberg/actions/SizeBasedFileRewriter.java:
##########
@@ -0,0 +1,320 @@
+/*
+ * 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.iceberg.actions;
+
+import java.math.RoundingMode;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import org.apache.iceberg.ContentFile;
+import org.apache.iceberg.ContentScanTask;
+import org.apache.iceberg.Table;
+import org.apache.iceberg.relocated.com.google.common.base.Preconditions;
+import org.apache.iceberg.relocated.com.google.common.collect.ImmutableSet;
+import org.apache.iceberg.relocated.com.google.common.collect.Maps;
+import org.apache.iceberg.relocated.com.google.common.math.LongMath;
+import org.apache.iceberg.util.BinPacking;
+import org.apache.iceberg.util.PropertyUtil;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * A file rewriter that determines which files to rewrite based on their size.
+ *
+ * <p>If files are smaller than the {@link #MIN_FILE_SIZE_BYTES} threshold or larger than the {@link
+ * #MAX_FILE_SIZE_BYTES} threshold, they are considered targets for being rewritten.
+ *
+ * <p>Once selected, files are grouped based on the {@link BinPacking bin-packing algorithm} into
+ * groups of no more than {@link #MAX_FILE_GROUP_SIZE_BYTES}. Groups will be actually rewritten if
+ * they contain more than {@link #MIN_INPUT_FILES} or if they would produce at least one file of
+ * {@link #TARGET_FILE_SIZE_BYTES}.
+ *
+ * <p>Note that implementations may add extra conditions for selecting files or filtering groups.
+ */
+abstract class SizeBasedFileRewriter<T extends ContentScanTask<F>, F extends ContentFile<F>>
+    implements FileRewriter<T, F> {
+
+  private static final Logger LOG = LoggerFactory.getLogger(SizeBasedFileRewriter.class);
+
+  /** The target output file size that this file rewriter will attempt to generate. */
+  public static final String TARGET_FILE_SIZE_BYTES = "target-file-size-bytes";
+
+  /**
+   * Adjusts files which will be considered for rewriting. Files smaller than this value will be
+   * considered for rewriting. This functions independently of {@link #MAX_FILE_SIZE_BYTES}.
+   *
+   * <p>Defaults to 75% of the target file size.
+   */
+  public static final String MIN_FILE_SIZE_BYTES = "min-file-size-bytes";
+
+  public static final double MIN_FILE_SIZE_DEFAULT_RATIO = 0.75;
+
+  /**
+   * Adjusts files which will be considered for rewriting. Files larger than this value will be
+   * considered for rewriting. This functions independently of {@link #MIN_FILE_SIZE_BYTES}.
+   *
+   * <p>Defaults to 180% of the target file size.
+   */
+  public static final String MAX_FILE_SIZE_BYTES = "max-file-size-bytes";
+
+  public static final double MAX_FILE_SIZE_DEFAULT_RATIO = 1.80;
+
+  /**
+   * The minimum number of files that need to be in a file group for it to be considered for
+   * compaction if the total size of that group is less than the target file size. This can also be
+   * thought of as the maximum number of wrongly sized files that could remain in a partition after
+   * rewriting.
+   */
+  public static final String MIN_INPUT_FILES = "min-input-files";
+
+  public static final int MIN_INPUT_FILES_DEFAULT = 5;
+
+  /** Overrides other options and forces rewriting of all files. */
+  public static final String REWRITE_ALL = "rewrite-all";
+
+  public static final boolean REWRITE_ALL_DEFAULT = false;
+
+  /**
+   * The entire rewrite operation is broken down into pieces based on partitioning and within

Review Comment:
   Also it's easier to read with a comma:
   
   The entire rewrite operation is broken down into pieces based on partitioning, and size-based groups within a partition.



##########
core/src/main/java/org/apache/iceberg/actions/FileRewriter.java:
##########
@@ -0,0 +1,81 @@
+/*
+ * 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.iceberg.actions;
+
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import org.apache.iceberg.ContentFile;
+import org.apache.iceberg.ContentScanTask;
+
+/**
+ * A class for rewriting content files.
+ *
+ * @param <T> the Java type of tasks to read content files
+ * @param <F> the Java type of content files
+ */
+public interface FileRewriter<T extends ContentScanTask<F>, F extends ContentFile<F>> {
+  /** Returns a description for this rewriter. */
+  default String description() {
+    return getClass().getName();
+  }
+
+  /**
+   * Returns a set of supported options for this rewriter. This is an allowed-list and any options
+   * not specified here will be rejected at runtime.
+   *
+   * @return returns a set of supported options
+   */
+  Set<String> validOptions();
+
+  /**
+   * Initializes this rewriter using provided options.
+   *
+   * @param options options to initialize this rewriter
+   */
+  void init(Map<String, String> options);
+
+  /**
+   * Selects files which this rewriter believes are valid targets to be rewritten.
+   *
+   * @param tasks an iterable of scan task for files in a partition
+   * @return the iterable containing only scan task for files to be rewritten
+   */
+  Iterable<T> selectFiles(Iterable<T> tasks);
+
+  /**
+   * Groups scan tasks into lists which will be processed in a single executable unit. Each group
+   * will end up being rewritten as an independent set of changes. This creates the jobs which will
+   * eventually be run by the underlying action.
+   *
+   * @param tasks an iterable of scan tasks for files to be rewritten
+   * @return the iterable of lists of scan tasks for files which will be processed together
+   */
+  Iterable<List<T>> planFileGroups(Iterable<T> tasks);

Review Comment:
   
   
   Optional: do you think 'plan' is necessary, or can we call it 'groupFiles'
   
   Also, it wasnt immediately clear, that not all tasks need to in a returned group.  I think we can document it.  Another option, going with this approach (having this interface define methods that filter/aggregate files), would it make sense  to make selectGroups into a separate API for clarity?
   
   



##########
core/src/main/java/org/apache/iceberg/actions/SizeBasedFileRewriter.java:
##########
@@ -0,0 +1,320 @@
+/*
+ * 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.iceberg.actions;
+
+import java.math.RoundingMode;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import org.apache.iceberg.ContentFile;
+import org.apache.iceberg.ContentScanTask;
+import org.apache.iceberg.Table;
+import org.apache.iceberg.relocated.com.google.common.base.Preconditions;
+import org.apache.iceberg.relocated.com.google.common.collect.ImmutableSet;
+import org.apache.iceberg.relocated.com.google.common.collect.Maps;
+import org.apache.iceberg.relocated.com.google.common.math.LongMath;
+import org.apache.iceberg.util.BinPacking;
+import org.apache.iceberg.util.PropertyUtil;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * A file rewriter that determines which files to rewrite based on their size.
+ *
+ * <p>If files are smaller than the {@link #MIN_FILE_SIZE_BYTES} threshold or larger than the {@link
+ * #MAX_FILE_SIZE_BYTES} threshold, they are considered targets for being rewritten.
+ *
+ * <p>Once selected, files are grouped based on the {@link BinPacking bin-packing algorithm} into
+ * groups of no more than {@link #MAX_FILE_GROUP_SIZE_BYTES}. Groups will be actually rewritten if
+ * they contain more than {@link #MIN_INPUT_FILES} or if they would produce at least one file of
+ * {@link #TARGET_FILE_SIZE_BYTES}.
+ *
+ * <p>Note that implementations may add extra conditions for selecting files or filtering groups.
+ */
+abstract class SizeBasedFileRewriter<T extends ContentScanTask<F>, F extends ContentFile<F>>
+    implements FileRewriter<T, F> {
+
+  private static final Logger LOG = LoggerFactory.getLogger(SizeBasedFileRewriter.class);
+
+  /** The target output file size that this file rewriter will attempt to generate. */
+  public static final String TARGET_FILE_SIZE_BYTES = "target-file-size-bytes";
+
+  /**
+   * Adjusts files which will be considered for rewriting. Files smaller than this value will be
+   * considered for rewriting. This functions independently of {@link #MAX_FILE_SIZE_BYTES}.
+   *
+   * <p>Defaults to 75% of the target file size.
+   */
+  public static final String MIN_FILE_SIZE_BYTES = "min-file-size-bytes";
+
+  public static final double MIN_FILE_SIZE_DEFAULT_RATIO = 0.75;
+
+  /**
+   * Adjusts files which will be considered for rewriting. Files larger than this value will be

Review Comment:
   Same comment as above



##########
core/src/main/java/org/apache/iceberg/actions/SizeBasedFileRewriter.java:
##########
@@ -0,0 +1,320 @@
+/*
+ * 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.iceberg.actions;
+
+import java.math.RoundingMode;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import org.apache.iceberg.ContentFile;
+import org.apache.iceberg.ContentScanTask;
+import org.apache.iceberg.Table;
+import org.apache.iceberg.relocated.com.google.common.base.Preconditions;
+import org.apache.iceberg.relocated.com.google.common.collect.ImmutableSet;
+import org.apache.iceberg.relocated.com.google.common.collect.Maps;
+import org.apache.iceberg.relocated.com.google.common.math.LongMath;
+import org.apache.iceberg.util.BinPacking;
+import org.apache.iceberg.util.PropertyUtil;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * A file rewriter that determines which files to rewrite based on their size.
+ *
+ * <p>If files are smaller than the {@link #MIN_FILE_SIZE_BYTES} threshold or larger than the {@link
+ * #MAX_FILE_SIZE_BYTES} threshold, they are considered targets for being rewritten.
+ *
+ * <p>Once selected, files are grouped based on the {@link BinPacking bin-packing algorithm} into
+ * groups of no more than {@link #MAX_FILE_GROUP_SIZE_BYTES}. Groups will be actually rewritten if
+ * they contain more than {@link #MIN_INPUT_FILES} or if they would produce at least one file of
+ * {@link #TARGET_FILE_SIZE_BYTES}.
+ *
+ * <p>Note that implementations may add extra conditions for selecting files or filtering groups.
+ */
+abstract class SizeBasedFileRewriter<T extends ContentScanTask<F>, F extends ContentFile<F>>
+    implements FileRewriter<T, F> {
+
+  private static final Logger LOG = LoggerFactory.getLogger(SizeBasedFileRewriter.class);
+
+  /** The target output file size that this file rewriter will attempt to generate. */
+  public static final String TARGET_FILE_SIZE_BYTES = "target-file-size-bytes";
+
+  /**
+   * Adjusts files which will be considered for rewriting. Files smaller than this value will be
+   * considered for rewriting. This functions independently of {@link #MAX_FILE_SIZE_BYTES}.
+   *
+   * <p>Defaults to 75% of the target file size.
+   */
+  public static final String MIN_FILE_SIZE_BYTES = "min-file-size-bytes";
+
+  public static final double MIN_FILE_SIZE_DEFAULT_RATIO = 0.75;
+
+  /**
+   * Adjusts files which will be considered for rewriting. Files larger than this value will be
+   * considered for rewriting. This functions independently of {@link #MIN_FILE_SIZE_BYTES}.
+   *
+   * <p>Defaults to 180% of the target file size.
+   */
+  public static final String MAX_FILE_SIZE_BYTES = "max-file-size-bytes";
+
+  public static final double MAX_FILE_SIZE_DEFAULT_RATIO = 1.80;
+
+  /**
+   * The minimum number of files that need to be in a file group for it to be considered for
+   * compaction if the total size of that group is less than the target file size. This can also be
+   * thought of as the maximum number of wrongly sized files that could remain in a partition after
+   * rewriting.
+   */
+  public static final String MIN_INPUT_FILES = "min-input-files";
+
+  public static final int MIN_INPUT_FILES_DEFAULT = 5;
+
+  /** Overrides other options and forces rewriting of all files. */
+  public static final String REWRITE_ALL = "rewrite-all";
+
+  public static final boolean REWRITE_ALL_DEFAULT = false;
+
+  /**
+   * The entire rewrite operation is broken down into pieces based on partitioning and within

Review Comment:
   This definition/context of 'file groups' is good, but shouldn't it be higher (maybe the class level?)  Some options higher up like MIN_INPUT_FILES already talk about file groups, and it misses this context.  (Up to ... refered to as file groups).



##########
core/src/main/java/org/apache/iceberg/actions/SizeBasedFileRewriter.java:
##########
@@ -0,0 +1,320 @@
+/*
+ * 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.iceberg.actions;
+
+import java.math.RoundingMode;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import org.apache.iceberg.ContentFile;
+import org.apache.iceberg.ContentScanTask;
+import org.apache.iceberg.Table;
+import org.apache.iceberg.relocated.com.google.common.base.Preconditions;
+import org.apache.iceberg.relocated.com.google.common.collect.ImmutableSet;
+import org.apache.iceberg.relocated.com.google.common.collect.Maps;
+import org.apache.iceberg.relocated.com.google.common.math.LongMath;
+import org.apache.iceberg.util.BinPacking;
+import org.apache.iceberg.util.PropertyUtil;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * A file rewriter that determines which files to rewrite based on their size.
+ *
+ * <p>If files are smaller than the {@link #MIN_FILE_SIZE_BYTES} threshold or larger than the {@link
+ * #MAX_FILE_SIZE_BYTES} threshold, they are considered targets for being rewritten.
+ *
+ * <p>Once selected, files are grouped based on the {@link BinPacking bin-packing algorithm} into
+ * groups of no more than {@link #MAX_FILE_GROUP_SIZE_BYTES}. Groups will be actually rewritten if
+ * they contain more than {@link #MIN_INPUT_FILES} or if they would produce at least one file of
+ * {@link #TARGET_FILE_SIZE_BYTES}.
+ *
+ * <p>Note that implementations may add extra conditions for selecting files or filtering groups.
+ */
+abstract class SizeBasedFileRewriter<T extends ContentScanTask<F>, F extends ContentFile<F>>
+    implements FileRewriter<T, F> {
+
+  private static final Logger LOG = LoggerFactory.getLogger(SizeBasedFileRewriter.class);
+
+  /** The target output file size that this file rewriter will attempt to generate. */
+  public static final String TARGET_FILE_SIZE_BYTES = "target-file-size-bytes";
+
+  /**
+   * Adjusts files which will be considered for rewriting. Files smaller than this value will be
+   * considered for rewriting. This functions independently of {@link #MAX_FILE_SIZE_BYTES}.
+   *
+   * <p>Defaults to 75% of the target file size.
+   */
+  public static final String MIN_FILE_SIZE_BYTES = "min-file-size-bytes";
+
+  public static final double MIN_FILE_SIZE_DEFAULT_RATIO = 0.75;
+
+  /**
+   * Adjusts files which will be considered for rewriting. Files larger than this value will be
+   * considered for rewriting. This functions independently of {@link #MIN_FILE_SIZE_BYTES}.
+   *
+   * <p>Defaults to 180% of the target file size.
+   */
+  public static final String MAX_FILE_SIZE_BYTES = "max-file-size-bytes";
+
+  public static final double MAX_FILE_SIZE_DEFAULT_RATIO = 1.80;
+
+  /**
+   * The minimum number of files that need to be in a file group for it to be considered for
+   * compaction if the total size of that group is less than the target file size. This can also be
+   * thought of as the maximum number of wrongly sized files that could remain in a partition after
+   * rewriting.
+   */
+  public static final String MIN_INPUT_FILES = "min-input-files";
+
+  public static final int MIN_INPUT_FILES_DEFAULT = 5;
+
+  /** Overrides other options and forces rewriting of all files. */
+  public static final String REWRITE_ALL = "rewrite-all";
+
+  public static final boolean REWRITE_ALL_DEFAULT = false;
+
+  /**
+   * The entire rewrite operation is broken down into pieces based on partitioning and within
+   * partitions based on size into groups. These subunits of the rewrite are referred to as file
+   * groups. This option controls the largest amount of data that should be rewritten in a single
+   * group. It helps with breaking down the rewriting of very large partitions which may not be
+   * rewritable otherwise due to the resource constraints of the cluster. For example, a sort-based
+   * rewrite may not scale to TB sized partitions, those partitions need to be worked on in small
+   * subsections to avoid exhaustion of resources.
+   *
+   * <p>When grouping files, the file rewriter will use this value to limit the files which will be

Review Comment:
   Same, I feel this context is more useful in class level.



##########
core/src/main/java/org/apache/iceberg/actions/SizeBasedFileRewriter.java:
##########
@@ -0,0 +1,320 @@
+/*
+ * 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.iceberg.actions;
+
+import java.math.RoundingMode;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import org.apache.iceberg.ContentFile;
+import org.apache.iceberg.ContentScanTask;
+import org.apache.iceberg.Table;
+import org.apache.iceberg.relocated.com.google.common.base.Preconditions;
+import org.apache.iceberg.relocated.com.google.common.collect.ImmutableSet;
+import org.apache.iceberg.relocated.com.google.common.collect.Maps;
+import org.apache.iceberg.relocated.com.google.common.math.LongMath;
+import org.apache.iceberg.util.BinPacking;
+import org.apache.iceberg.util.PropertyUtil;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * A file rewriter that determines which files to rewrite based on their size.
+ *
+ * <p>If files are smaller than the {@link #MIN_FILE_SIZE_BYTES} threshold or larger than the {@link
+ * #MAX_FILE_SIZE_BYTES} threshold, they are considered targets for being rewritten.
+ *
+ * <p>Once selected, files are grouped based on the {@link BinPacking bin-packing algorithm} into
+ * groups of no more than {@link #MAX_FILE_GROUP_SIZE_BYTES}. Groups will be actually rewritten if
+ * they contain more than {@link #MIN_INPUT_FILES} or if they would produce at least one file of
+ * {@link #TARGET_FILE_SIZE_BYTES}.
+ *
+ * <p>Note that implementations may add extra conditions for selecting files or filtering groups.
+ */
+abstract class SizeBasedFileRewriter<T extends ContentScanTask<F>, F extends ContentFile<F>>
+    implements FileRewriter<T, F> {
+
+  private static final Logger LOG = LoggerFactory.getLogger(SizeBasedFileRewriter.class);
+
+  /** The target output file size that this file rewriter will attempt to generate. */
+  public static final String TARGET_FILE_SIZE_BYTES = "target-file-size-bytes";
+
+  /**
+   * Adjusts files which will be considered for rewriting. Files smaller than this value will be
+   * considered for rewriting. This functions independently of {@link #MAX_FILE_SIZE_BYTES}.
+   *
+   * <p>Defaults to 75% of the target file size.
+   */
+  public static final String MIN_FILE_SIZE_BYTES = "min-file-size-bytes";
+
+  public static final double MIN_FILE_SIZE_DEFAULT_RATIO = 0.75;
+
+  /**
+   * Adjusts files which will be considered for rewriting. Files larger than this value will be
+   * considered for rewriting. This functions independently of {@link #MIN_FILE_SIZE_BYTES}.
+   *
+   * <p>Defaults to 180% of the target file size.
+   */
+  public static final String MAX_FILE_SIZE_BYTES = "max-file-size-bytes";
+
+  public static final double MAX_FILE_SIZE_DEFAULT_RATIO = 1.80;
+
+  /**
+   * The minimum number of files that need to be in a file group for it to be considered for
+   * compaction if the total size of that group is less than the target file size. This can also be
+   * thought of as the maximum number of wrongly sized files that could remain in a partition after
+   * rewriting.
+   */
+  public static final String MIN_INPUT_FILES = "min-input-files";
+
+  public static final int MIN_INPUT_FILES_DEFAULT = 5;
+
+  /** Overrides other options and forces rewriting of all files. */
+  public static final String REWRITE_ALL = "rewrite-all";
+
+  public static final boolean REWRITE_ALL_DEFAULT = false;
+
+  /**
+   * The entire rewrite operation is broken down into pieces based on partitioning and within
+   * partitions based on size into groups. These subunits of the rewrite are referred to as file
+   * groups. This option controls the largest amount of data that should be rewritten in a single
+   * group. It helps with breaking down the rewriting of very large partitions which may not be
+   * rewritable otherwise due to the resource constraints of the cluster. For example, a sort-based
+   * rewrite may not scale to TB sized partitions, those partitions need to be worked on in small
+   * subsections to avoid exhaustion of resources.
+   *
+   * <p>When grouping files, the file rewriter will use this value to limit the files which will be
+   * included in a single file group. A group will be processed by a single framework "action". For
+   * example, in Spark this means that each group would be rewritten in its own Spark job. A group
+   * will never contain files for multiple output partitions.
+   */
+  public static final String MAX_FILE_GROUP_SIZE_BYTES = "max-file-group-size-bytes";
+
+  public static final long MAX_FILE_GROUP_SIZE_BYTES_DEFAULT = 100L * 1024 * 1024 * 1024; // 100 GB
+
+  private final Table table;
+  private long targetFileSize;
+  private long minFileSize;
+  private long maxFileSize;
+  private int minInputFiles;
+  private boolean rewriteAll;
+  private long maxGroupSize;
+
+  protected SizeBasedFileRewriter(Table table) {
+    this.table = table;
+  }
+
+  protected abstract long defaultTargetFileSize();
+
+  protected abstract Iterable<T> doSelectFiles(Iterable<T> tasks);
+
+  protected abstract List<List<T>> filterFileGroups(List<List<T>> groups);
+
+  protected Table table() {
+    return table;
+  }
+
+  @Override
+  public Set<String> validOptions() {
+    return ImmutableSet.of(
+        TARGET_FILE_SIZE_BYTES,
+        MIN_FILE_SIZE_BYTES,
+        MAX_FILE_SIZE_BYTES,
+        MIN_INPUT_FILES,
+        REWRITE_ALL,
+        MAX_FILE_GROUP_SIZE_BYTES);
+  }
+
+  @Override
+  public void init(Map<String, String> options) {
+    Map<String, Long> sizeThresholds = sizeThresholds(options);
+    this.targetFileSize = sizeThresholds.get(TARGET_FILE_SIZE_BYTES);
+    this.minFileSize = sizeThresholds.get(MIN_FILE_SIZE_BYTES);
+    this.maxFileSize = sizeThresholds.get(MAX_FILE_SIZE_BYTES);
+
+    this.minInputFiles = minInputFiles(options);
+    this.rewriteAll = rewriteAll(options);
+    this.maxGroupSize = maxGroupSize(options);
+
+    if (rewriteAll) {
+      LOG.info("Configured to rewrite all provided files in table {}", table.name());
+    }
+  }
+
+  @Override
+  public Iterable<T> selectFiles(Iterable<T> tasks) {
+    return rewriteAll ? tasks : doSelectFiles(tasks);
+  }
+
+  protected boolean hasSuboptimalSize(T task) {
+    return task.length() < minFileSize || task.length() > maxFileSize;
+  }
+
+  @Override
+  public Iterable<List<T>> planFileGroups(Iterable<T> tasks) {
+    BinPacking.ListPacker<T> packer = new BinPacking.ListPacker<>(maxGroupSize, 1, false);
+    List<List<T>> groups = packer.pack(tasks, ContentScanTask::length);
+    return rewriteAll ? groups : filterFileGroups(groups);
+  }
+
+  protected boolean hasEnoughInputFiles(List<T> group) {
+    return group.size() > 1 && group.size() >= minInputFiles;
+  }
+
+  protected boolean hasEnoughData(List<T> group) {
+    return group.size() > 1 && inputSize(group) > targetFileSize;
+  }
+
+  protected boolean hasTooMuchData(List<T> group) {
+    return inputSize(group) > maxFileSize;
+  }
+
+  protected long inputSize(List<T> group) {
+    return group.stream().mapToLong(ContentScanTask::length).sum();
+  }
+
+  /**
+   * Determines the preferable number of output files when rewriting a particular file group.
+   *
+   * <p>If the rewriter is handling 10.1 GB of data with a target file size of 1 GB, it could
+   * produce 11 files, one of which would only have 0.1 GB. This would most likely be less
+   * preferable to 10 files with 1.01 GB each. So this method decides whether to round up or round
+   * down based on what the estimated average file size will be if the remainder (0.1 GB) is
+   * distributed amongst other files. If the new average file size is no more than 10% greater than
+   * the target file size, then this method will round down when determining the number of output
+   * files. Otherwise, the remainder will be written into a separate file.
+   *
+   * @param inputSize a total input size for a file group
+   * @return the number of files this rewriter should create
+   */
+  protected long numOutputFiles(long inputSize) {
+    if (inputSize < targetFileSize) {
+      return 1;
+    }
+
+    long numFilesWithRemainder = LongMath.divide(inputSize, targetFileSize, RoundingMode.CEILING);
+    long numFilesWithoutRemainder = LongMath.divide(inputSize, targetFileSize, RoundingMode.FLOOR);
+    long avgFileSizeWithoutRemainder = inputSize / numFilesWithoutRemainder;
+
+    if (LongMath.mod(inputSize, targetFileSize) > minFileSize) {
+      // the remainder file is of a valid size for this rewrite so keep it
+      return numFilesWithRemainder;
+
+    } else if (avgFileSizeWithoutRemainder < Math.min(1.1 * targetFileSize, writeMaxFileSize())) {
+      // if the reminder is distributed amongst other files,
+      // the average file size will be no more than 10% bigger than the target file size
+      // so round down and distribute remainder amongst other files
+      return numFilesWithoutRemainder;
+
+    } else {
+      // keep the remainder file as it is not OK to distribute it amongst other files
+      return numFilesWithRemainder;
+    }
+  }
+
+  /**
+   * Estimates a larger max target file size than the target size used in task creation to avoid
+   * tasks which are predicted to have a certain size, but exceed that target size when serde is
+   * complete creating tiny remainder files.
+   *
+   * <p>While we create tasks that should all be smaller than our target size, there is a chance
+   * that the actual data will end up being larger than our target size due to various factors of
+   * compression, serialization and other factors outside our control. If this occurs, instead of
+   * making a single file that is close in size to our target, we would end up producing one file of
+   * the target size, and then a small extra file with the remaining data. For example, if our

Review Comment:
   Suggest to put "For example" on new paragraph



##########
core/src/main/java/org/apache/iceberg/actions/SizeBasedFileRewriter.java:
##########
@@ -0,0 +1,320 @@
+/*
+ * 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.iceberg.actions;
+
+import java.math.RoundingMode;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import org.apache.iceberg.ContentFile;
+import org.apache.iceberg.ContentScanTask;
+import org.apache.iceberg.Table;
+import org.apache.iceberg.relocated.com.google.common.base.Preconditions;
+import org.apache.iceberg.relocated.com.google.common.collect.ImmutableSet;
+import org.apache.iceberg.relocated.com.google.common.collect.Maps;
+import org.apache.iceberg.relocated.com.google.common.math.LongMath;
+import org.apache.iceberg.util.BinPacking;
+import org.apache.iceberg.util.PropertyUtil;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * A file rewriter that determines which files to rewrite based on their size.
+ *
+ * <p>If files are smaller than the {@link #MIN_FILE_SIZE_BYTES} threshold or larger than the {@link
+ * #MAX_FILE_SIZE_BYTES} threshold, they are considered targets for being rewritten.
+ *
+ * <p>Once selected, files are grouped based on the {@link BinPacking bin-packing algorithm} into
+ * groups of no more than {@link #MAX_FILE_GROUP_SIZE_BYTES}. Groups will be actually rewritten if
+ * they contain more than {@link #MIN_INPUT_FILES} or if they would produce at least one file of
+ * {@link #TARGET_FILE_SIZE_BYTES}.
+ *
+ * <p>Note that implementations may add extra conditions for selecting files or filtering groups.
+ */
+abstract class SizeBasedFileRewriter<T extends ContentScanTask<F>, F extends ContentFile<F>>
+    implements FileRewriter<T, F> {
+
+  private static final Logger LOG = LoggerFactory.getLogger(SizeBasedFileRewriter.class);
+
+  /** The target output file size that this file rewriter will attempt to generate. */
+  public static final String TARGET_FILE_SIZE_BYTES = "target-file-size-bytes";
+
+  /**
+   * Adjusts files which will be considered for rewriting. Files smaller than this value will be
+   * considered for rewriting. This functions independently of {@link #MAX_FILE_SIZE_BYTES}.
+   *
+   * <p>Defaults to 75% of the target file size.
+   */
+  public static final String MIN_FILE_SIZE_BYTES = "min-file-size-bytes";
+
+  public static final double MIN_FILE_SIZE_DEFAULT_RATIO = 0.75;
+
+  /**
+   * Adjusts files which will be considered for rewriting. Files larger than this value will be
+   * considered for rewriting. This functions independently of {@link #MIN_FILE_SIZE_BYTES}.
+   *
+   * <p>Defaults to 180% of the target file size.
+   */
+  public static final String MAX_FILE_SIZE_BYTES = "max-file-size-bytes";
+
+  public static final double MAX_FILE_SIZE_DEFAULT_RATIO = 1.80;
+
+  /**
+   * The minimum number of files that need to be in a file group for it to be considered for
+   * compaction if the total size of that group is less than the target file size. This can also be
+   * thought of as the maximum number of wrongly sized files that could remain in a partition after
+   * rewriting.
+   */
+  public static final String MIN_INPUT_FILES = "min-input-files";
+
+  public static final int MIN_INPUT_FILES_DEFAULT = 5;
+
+  /** Overrides other options and forces rewriting of all files. */
+  public static final String REWRITE_ALL = "rewrite-all";
+
+  public static final boolean REWRITE_ALL_DEFAULT = false;
+
+  /**
+   * The entire rewrite operation is broken down into pieces based on partitioning and within
+   * partitions based on size into groups. These subunits of the rewrite are referred to as file
+   * groups. This option controls the largest amount of data that should be rewritten in a single
+   * group. It helps with breaking down the rewriting of very large partitions which may not be
+   * rewritable otherwise due to the resource constraints of the cluster. For example, a sort-based
+   * rewrite may not scale to TB sized partitions, those partitions need to be worked on in small

Review Comment:
   Nit: missing and
   
   ``` TB-sized partitions, and those partitions```



##########
core/src/main/java/org/apache/iceberg/actions/FileRewriter.java:
##########
@@ -0,0 +1,81 @@
+/*
+ * 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.iceberg.actions;
+
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import org.apache.iceberg.ContentFile;
+import org.apache.iceberg.ContentScanTask;
+
+/**
+ * A class for rewriting content files.
+ *
+ * @param <T> the Java type of tasks to read content files
+ * @param <F> the Java type of content files
+ */
+public interface FileRewriter<T extends ContentScanTask<F>, F extends ContentFile<F>> {
+  /** Returns a description for this rewriter. */
+  default String description() {
+    return getClass().getName();
+  }
+
+  /**
+   * Returns a set of supported options for this rewriter. This is an allowed-list and any options
+   * not specified here will be rejected at runtime.
+   *
+   * @return returns a set of supported options

Review Comment:
   Is return annotation  redundant? (comparing with other javadoc comments)



##########
core/src/main/java/org/apache/iceberg/actions/SizeBasedFileRewriter.java:
##########
@@ -0,0 +1,320 @@
+/*
+ * 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.iceberg.actions;
+
+import java.math.RoundingMode;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import org.apache.iceberg.ContentFile;
+import org.apache.iceberg.ContentScanTask;
+import org.apache.iceberg.Table;
+import org.apache.iceberg.relocated.com.google.common.base.Preconditions;
+import org.apache.iceberg.relocated.com.google.common.collect.ImmutableSet;
+import org.apache.iceberg.relocated.com.google.common.collect.Maps;
+import org.apache.iceberg.relocated.com.google.common.math.LongMath;
+import org.apache.iceberg.util.BinPacking;
+import org.apache.iceberg.util.PropertyUtil;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * A file rewriter that determines which files to rewrite based on their size.
+ *
+ * <p>If files are smaller than the {@link #MIN_FILE_SIZE_BYTES} threshold or larger than the {@link
+ * #MAX_FILE_SIZE_BYTES} threshold, they are considered targets for being rewritten.
+ *
+ * <p>Once selected, files are grouped based on the {@link BinPacking bin-packing algorithm} into
+ * groups of no more than {@link #MAX_FILE_GROUP_SIZE_BYTES}. Groups will be actually rewritten if
+ * they contain more than {@link #MIN_INPUT_FILES} or if they would produce at least one file of
+ * {@link #TARGET_FILE_SIZE_BYTES}.
+ *
+ * <p>Note that implementations may add extra conditions for selecting files or filtering groups.
+ */
+abstract class SizeBasedFileRewriter<T extends ContentScanTask<F>, F extends ContentFile<F>>
+    implements FileRewriter<T, F> {
+
+  private static final Logger LOG = LoggerFactory.getLogger(SizeBasedFileRewriter.class);
+
+  /** The target output file size that this file rewriter will attempt to generate. */
+  public static final String TARGET_FILE_SIZE_BYTES = "target-file-size-bytes";
+
+  /**
+   * Adjusts files which will be considered for rewriting. Files smaller than this value will be
+   * considered for rewriting. This functions independently of {@link #MAX_FILE_SIZE_BYTES}.
+   *
+   * <p>Defaults to 75% of the target file size.
+   */
+  public static final String MIN_FILE_SIZE_BYTES = "min-file-size-bytes";
+
+  public static final double MIN_FILE_SIZE_DEFAULT_RATIO = 0.75;
+
+  /**
+   * Adjusts files which will be considered for rewriting. Files larger than this value will be
+   * considered for rewriting. This functions independently of {@link #MIN_FILE_SIZE_BYTES}.
+   *
+   * <p>Defaults to 180% of the target file size.
+   */
+  public static final String MAX_FILE_SIZE_BYTES = "max-file-size-bytes";
+
+  public static final double MAX_FILE_SIZE_DEFAULT_RATIO = 1.80;
+
+  /**
+   * The minimum number of files that need to be in a file group for it to be considered for
+   * compaction if the total size of that group is less than the target file size. This can also be
+   * thought of as the maximum number of wrongly sized files that could remain in a partition after
+   * rewriting.
+   */
+  public static final String MIN_INPUT_FILES = "min-input-files";
+
+  public static final int MIN_INPUT_FILES_DEFAULT = 5;
+
+  /** Overrides other options and forces rewriting of all files. */
+  public static final String REWRITE_ALL = "rewrite-all";
+
+  public static final boolean REWRITE_ALL_DEFAULT = false;
+
+  /**
+   * The entire rewrite operation is broken down into pieces based on partitioning and within
+   * partitions based on size into groups. These subunits of the rewrite are referred to as file
+   * groups. This option controls the largest amount of data that should be rewritten in a single
+   * group. It helps with breaking down the rewriting of very large partitions which may not be
+   * rewritable otherwise due to the resource constraints of the cluster. For example, a sort-based
+   * rewrite may not scale to TB sized partitions, those partitions need to be worked on in small
+   * subsections to avoid exhaustion of resources.
+   *
+   * <p>When grouping files, the file rewriter will use this value to limit the files which will be
+   * included in a single file group. A group will be processed by a single framework "action". For
+   * example, in Spark this means that each group would be rewritten in its own Spark job. A group
+   * will never contain files for multiple output partitions.
+   */
+  public static final String MAX_FILE_GROUP_SIZE_BYTES = "max-file-group-size-bytes";
+
+  public static final long MAX_FILE_GROUP_SIZE_BYTES_DEFAULT = 100L * 1024 * 1024 * 1024; // 100 GB
+
+  private final Table table;
+  private long targetFileSize;
+  private long minFileSize;
+  private long maxFileSize;
+  private int minInputFiles;
+  private boolean rewriteAll;
+  private long maxGroupSize;
+
+  protected SizeBasedFileRewriter(Table table) {
+    this.table = table;
+  }
+
+  protected abstract long defaultTargetFileSize();
+
+  protected abstract Iterable<T> doSelectFiles(Iterable<T> tasks);
+
+  protected abstract List<List<T>> filterFileGroups(List<List<T>> groups);
+
+  protected Table table() {
+    return table;
+  }
+
+  @Override
+  public Set<String> validOptions() {
+    return ImmutableSet.of(
+        TARGET_FILE_SIZE_BYTES,
+        MIN_FILE_SIZE_BYTES,
+        MAX_FILE_SIZE_BYTES,
+        MIN_INPUT_FILES,
+        REWRITE_ALL,
+        MAX_FILE_GROUP_SIZE_BYTES);
+  }
+
+  @Override
+  public void init(Map<String, String> options) {
+    Map<String, Long> sizeThresholds = sizeThresholds(options);
+    this.targetFileSize = sizeThresholds.get(TARGET_FILE_SIZE_BYTES);
+    this.minFileSize = sizeThresholds.get(MIN_FILE_SIZE_BYTES);
+    this.maxFileSize = sizeThresholds.get(MAX_FILE_SIZE_BYTES);
+
+    this.minInputFiles = minInputFiles(options);
+    this.rewriteAll = rewriteAll(options);
+    this.maxGroupSize = maxGroupSize(options);
+
+    if (rewriteAll) {
+      LOG.info("Configured to rewrite all provided files in table {}", table.name());
+    }
+  }
+
+  @Override
+  public Iterable<T> selectFiles(Iterable<T> tasks) {
+    return rewriteAll ? tasks : doSelectFiles(tasks);
+  }
+
+  protected boolean hasSuboptimalSize(T task) {
+    return task.length() < minFileSize || task.length() > maxFileSize;
+  }
+
+  @Override
+  public Iterable<List<T>> planFileGroups(Iterable<T> tasks) {
+    BinPacking.ListPacker<T> packer = new BinPacking.ListPacker<>(maxGroupSize, 1, false);
+    List<List<T>> groups = packer.pack(tasks, ContentScanTask::length);
+    return rewriteAll ? groups : filterFileGroups(groups);
+  }
+
+  protected boolean hasEnoughInputFiles(List<T> group) {
+    return group.size() > 1 && group.size() >= minInputFiles;
+  }
+
+  protected boolean hasEnoughData(List<T> group) {
+    return group.size() > 1 && inputSize(group) > targetFileSize;
+  }
+
+  protected boolean hasTooMuchData(List<T> group) {
+    return inputSize(group) > maxFileSize;
+  }
+
+  protected long inputSize(List<T> group) {
+    return group.stream().mapToLong(ContentScanTask::length).sum();
+  }
+
+  /**
+   * Determines the preferable number of output files when rewriting a particular file group.
+   *
+   * <p>If the rewriter is handling 10.1 GB of data with a target file size of 1 GB, it could
+   * produce 11 files, one of which would only have 0.1 GB. This would most likely be less
+   * preferable to 10 files with 1.01 GB each. So this method decides whether to round up or round
+   * down based on what the estimated average file size will be if the remainder (0.1 GB) is
+   * distributed amongst other files. If the new average file size is no more than 10% greater than
+   * the target file size, then this method will round down when determining the number of output
+   * files. Otherwise, the remainder will be written into a separate file.
+   *
+   * @param inputSize a total input size for a file group
+   * @return the number of files this rewriter should create
+   */
+  protected long numOutputFiles(long inputSize) {
+    if (inputSize < targetFileSize) {
+      return 1;
+    }
+
+    long numFilesWithRemainder = LongMath.divide(inputSize, targetFileSize, RoundingMode.CEILING);
+    long numFilesWithoutRemainder = LongMath.divide(inputSize, targetFileSize, RoundingMode.FLOOR);
+    long avgFileSizeWithoutRemainder = inputSize / numFilesWithoutRemainder;
+
+    if (LongMath.mod(inputSize, targetFileSize) > minFileSize) {
+      // the remainder file is of a valid size for this rewrite so keep it
+      return numFilesWithRemainder;
+
+    } else if (avgFileSizeWithoutRemainder < Math.min(1.1 * targetFileSize, writeMaxFileSize())) {
+      // if the reminder is distributed amongst other files,
+      // the average file size will be no more than 10% bigger than the target file size
+      // so round down and distribute remainder amongst other files
+      return numFilesWithoutRemainder;
+
+    } else {
+      // keep the remainder file as it is not OK to distribute it amongst other files
+      return numFilesWithRemainder;
+    }
+  }
+
+  /**
+   * Estimates a larger max target file size than the target size used in task creation to avoid
+   * tasks which are predicted to have a certain size, but exceed that target size when serde is
+   * complete creating tiny remainder files.

Review Comment:
   Also I realize this explanation is just repeated on the below paragraph.  Can't this be simpler and just be:
   
   
   "Estimates a larger max target file size than the target size used in task creation to avoid creating tiny remainder files."



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