[core] Introduce delete-file.thread-num (#3751)

docs/layouts/shortcodes/generated/core_configuration.html

@@ -194,6 +194,12 @@
             <td>Duration</td>
             <td>The TTL in rocksdb index for cross partition upsert (primary keys not contain all partition fields), this can avoid maintaining too many indexes and lead to worse and worse performance, but please note that this may also cause data duplication.</td>
         </tr>
+        <tr>
+            <td><h5>delete-file.thread-num</h5></td>
+            <td style="word-wrap: break-word;">(none)</td>
+            <td>Integer</td>
+            <td>The maximum number of concurrent deleting files. By default is the number of processors available to the Java virtual machine.</td>
+        </tr>
         <tr>
             <td><h5>delete.force-produce-changelog</h5></td>
             <td style="word-wrap: break-word;">false</td>

paimon-common/src/main/java/org/apache/paimon/CoreOptions.java

@@ -1284,6 +1284,14 @@ public class CoreOptions implements Serializable {
                             "When set to true, produce Iceberg metadata after a snapshot is committed, "
                                     + "so that Iceberg readers can read Paimon's raw files.");
 
+    public static final ConfigOption<Integer> DELETE_FILE_THREAD_NUM =
+            key("delete-file.thread-num")
+                    .intType()
+                    .noDefaultValue()
+                    .withDescription(
+                            "The maximum number of concurrent deleting files. "
+                                    + "By default is the number of processors available to the Java virtual machine.");
+
     private final Options options;
 
     public CoreOptions(Map<String, String> options) {
@@ -1508,6 +1516,11 @@ public boolean cleanEmptyDirectories() {
         return options.get(SNAPSHOT_CLEAN_EMPTY_DIRECTORIES);
     }
 
+    public int deleteFileThreadNum() {
+        return options.getOptional(DELETE_FILE_THREAD_NUM)
+                .orElseGet(() -> Runtime.getRuntime().availableProcessors());
+    }
+
     public ExpireConfig expireConfig() {
         return ExpireConfig.builder()
                 .snapshotRetainMax(snapshotNumRetainMax())

paimon-common/src/main/java/org/apache/paimon/utils/FileDeletionThreadPool.java

@@ -0,0 +1,55 @@
+/*
+ * 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.paimon.utils;
+
+import org.apache.paimon.fs.FileIO;
+
+import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.ThreadPoolExecutor;
+import java.util.concurrent.TimeUnit;
+
+import static org.apache.paimon.utils.ThreadUtils.newDaemonThreadFactory;
+
+/** Thread pool to delete files using {@link FileIO}. */
+public class FileDeletionThreadPool {
+
+    private static ThreadPoolExecutor executorService =
+            createCachedThreadPool(Runtime.getRuntime().availableProcessors());
+
+    public static synchronized ThreadPoolExecutor getExecutorService(int threadNum) {
+        if (threadNum <= executorService.getMaximumPoolSize()) {
+            return executorService;
+        }
+        // we don't need to close previous pool
+        // it is just cached pool
+        executorService = createCachedThreadPool(threadNum);
+
+        return executorService;
+    }
+
+    private static ThreadPoolExecutor createCachedThreadPool(int threadNum) {
+        return new ThreadPoolExecutor(
+                0,
+                threadNum,
+                1,
+                TimeUnit.MINUTES,
+                new LinkedBlockingQueue<>(),
+                newDaemonThreadFactory("DELETE-FILE-THREAD-POOL"));
+    }
+}

paimon-core/src/main/java/org/apache/paimon/AbstractFileStore.java

@@ -218,7 +218,8 @@ public SnapshotDeletion newSnapshotDeletion() {
                 newIndexFileHandler(),
                 newStatsFileHandler(),
                 options.changelogProducer() != CoreOptions.ChangelogProducer.NONE,
-                options.cleanEmptyDirectories());
+                options.cleanEmptyDirectories(),
+                options.deleteFileThreadNum());
     }
 
     @Override
@@ -230,7 +231,8 @@ public ChangelogDeletion newChangelogDeletion() {
                 manifestListFactory().create(),
                 newIndexFileHandler(),
                 newStatsFileHandler(),
-                options.cleanEmptyDirectories());
+                options.cleanEmptyDirectories(),
+                options.deleteFileThreadNum());
     }
 
     @Override
@@ -247,7 +249,8 @@ public TagDeletion newTagDeletion() {
                 manifestListFactory().create(),
                 newIndexFileHandler(),
                 newStatsFileHandler(),
-                options.cleanEmptyDirectories());
+                options.cleanEmptyDirectories(),
+                options.deleteFileThreadNum());
     }
 
     public abstract Comparator<InternalRow> newKeyComparator();

paimon-core/src/main/java/org/apache/paimon/operation/ChangelogDeletion.java

@@ -46,15 +46,17 @@ public ChangelogDeletion(
             ManifestList manifestList,
             IndexFileHandler indexFileHandler,
             StatsFileHandler statsFileHandler,
-            boolean cleanEmptyDirectories) {
+            boolean cleanEmptyDirectories,
+            int deleteFileThreadNum) {
         super(
                 fileIO,
                 pathFactory,
                 manifestFile,
                 manifestList,
                 indexFileHandler,
                 statsFileHandler,
-                cleanEmptyDirectories);
+                cleanEmptyDirectories,
+                deleteFileThreadNum);
     }
 
     @Override

paimon-core/src/main/java/org/apache/paimon/operation/FileDeletionBase.java

@@ -32,8 +32,8 @@
 import org.apache.paimon.manifest.ManifestFileMeta;
 import org.apache.paimon.manifest.ManifestList;
 import org.apache.paimon.stats.StatsFileHandler;
+import org.apache.paimon.utils.FileDeletionThreadPool;
 import org.apache.paimon.utils.FileStorePathFactory;
-import org.apache.paimon.utils.FileUtils;
 import org.apache.paimon.utils.Pair;
 import org.apache.paimon.utils.TagManager;
 
@@ -71,9 +71,10 @@ public abstract class FileDeletionBase<T extends Snapshot> {
     protected final IndexFileHandler indexFileHandler;
     protected final StatsFileHandler statsFileHandler;
     private final boolean cleanEmptyDirectories;
-
     protected final Map<BinaryRow, Set<Integer>> deletionBuckets;
-    protected final Executor ioExecutor;
+
+    private final Executor deleteFileExecutor;
+
     protected boolean changelogDecoupled;
 
     /** Used to record which tag is cached. */
@@ -89,7 +90,8 @@ public FileDeletionBase(
             ManifestList manifestList,
             IndexFileHandler indexFileHandler,
             StatsFileHandler statsFileHandler,
-            boolean cleanEmptyDirectories) {
+            boolean cleanEmptyDirectories,
+            int deleteFileThreadNum) {
         this.fileIO = fileIO;
         this.pathFactory = pathFactory;
         this.manifestFile = manifestFile;
@@ -98,7 +100,7 @@ public FileDeletionBase(
         this.statsFileHandler = statsFileHandler;
         this.cleanEmptyDirectories = cleanEmptyDirectories;
         this.deletionBuckets = new HashMap<>();
-        this.ioExecutor = FileUtils.COMMON_IO_FORK_JOIN_POOL;
+        this.deleteFileExecutor = FileDeletionThreadPool.getExecutorService(deleteFileThreadNum);
     }
 
     /**
@@ -455,15 +457,15 @@ private boolean tryDeleteEmptyDirectory(Path path) {
         }
     }
 
-    protected <T> void deleteFiles(Collection<T> files, Consumer<T> deletion) {
+    protected <F> void deleteFiles(Collection<F> files, Consumer<F> deletion) {
         if (files.isEmpty()) {
             return;
         }
 
         List<CompletableFuture<Void>> deletionFutures = new ArrayList<>(files.size());
-        for (T file : files) {
+        for (F file : files) {
             deletionFutures.add(
-                    CompletableFuture.runAsync(() -> deletion.accept(file), ioExecutor));
+                    CompletableFuture.runAsync(() -> deletion.accept(file), deleteFileExecutor));
         }
 
         try {

paimon-core/src/main/java/org/apache/paimon/operation/SnapshotDeletion.java

@@ -50,15 +50,17 @@ public SnapshotDeletion(
             IndexFileHandler indexFileHandler,
             StatsFileHandler statsFileHandler,
             boolean produceChangelog,
-            boolean cleanEmptyDirectories) {
+            boolean cleanEmptyDirectories,
+            int deleteFileThreadNum) {
         super(
                 fileIO,
                 pathFactory,
                 manifestFile,
                 manifestList,
                 indexFileHandler,
                 statsFileHandler,
-                cleanEmptyDirectories);
+                cleanEmptyDirectories,
+                deleteFileThreadNum);
         this.produceChangelog = produceChangelog;
     }
 

paimon-core/src/main/java/org/apache/paimon/operation/TagDeletion.java

@@ -54,15 +54,17 @@ public TagDeletion(
             ManifestList manifestList,
             IndexFileHandler indexFileHandler,
             StatsFileHandler statsFileHandler,
-            boolean cleanEmptyDirectories) {
+            boolean cleanEmptyDirectories,
+            int deleteFileThreadNum) {
         super(
                 fileIO,
                 pathFactory,
                 manifestFile,
                 manifestList,
                 indexFileHandler,
                 statsFileHandler,
-                cleanEmptyDirectories);
+                cleanEmptyDirectories,
+                deleteFileThreadNum);
     }
 
     @Override