| /* |
| * 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.cassandra.io.sstable; |
| |
| import java.io.File; |
| import java.util.Collections; |
| import java.util.Queue; |
| import java.util.Set; |
| import java.util.concurrent.ConcurrentLinkedQueue; |
| import java.util.concurrent.TimeUnit; |
| |
| import com.google.common.annotations.VisibleForTesting; |
| import com.google.common.collect.Sets; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import com.codahale.metrics.Counter; |
| import org.apache.cassandra.concurrent.ScheduledExecutors; |
| import org.apache.cassandra.utils.FBUtilities; |
| import org.apache.cassandra.utils.concurrent.Blocker; |
| |
| public class SSTableDeletingTask implements Runnable |
| { |
| private static final Logger logger = LoggerFactory.getLogger(SSTableDeletingTask.class); |
| |
| // Deleting sstables is tricky because the mmapping might not have been finalized yet, |
| // and delete will fail (on Windows) until it is (we only force the unmapping on SUN VMs). |
| // Additionally, we need to make sure to delete the data file first, so on restart the others |
| // will be recognized as GCable. |
| private static final Queue<Runnable> failedTasks = new ConcurrentLinkedQueue<>(); |
| private static final Blocker blocker = new Blocker(); |
| |
| private final Descriptor desc; |
| private final Set<Component> components; |
| private final long bytesOnDisk; |
| private final Counter totalDiskSpaceUsed; |
| |
| /** |
| * realDescriptor is the actual descriptor for the sstable, the descriptor inside |
| * referent can be 'faked' as FINAL for early opened files. We need the real one |
| * to be able to remove the files. |
| */ |
| public SSTableDeletingTask(Descriptor realDescriptor, Set<Component> components, Counter totalDiskSpaceUsed, long bytesOnDisk) |
| { |
| this.desc = realDescriptor; |
| this.bytesOnDisk = bytesOnDisk; |
| this.totalDiskSpaceUsed = totalDiskSpaceUsed; |
| switch (desc.type) |
| { |
| case FINAL: |
| this.components = components; |
| break; |
| case TEMPLINK: |
| this.components = Sets.newHashSet(Component.DATA, Component.PRIMARY_INDEX); |
| break; |
| default: |
| throw new IllegalStateException(); |
| } |
| } |
| |
| public void run() |
| { |
| blocker.ask(); |
| // If we can't successfully delete the DATA component, set the task to be retried later: see above |
| File datafile = new File(desc.filenameFor(Component.DATA)); |
| if (!datafile.delete()) |
| { |
| logger.error("Unable to delete {} (it will be removed on server restart; we'll also retry after GC)", datafile); |
| failedTasks.add(this); |
| return; |
| } |
| // let the remainder be cleaned up by delete |
| SSTable.delete(desc, Sets.difference(components, Collections.singleton(Component.DATA))); |
| if (totalDiskSpaceUsed != null) |
| totalDiskSpaceUsed.dec(bytesOnDisk); |
| } |
| |
| /** |
| * Retry all deletions that failed the first time around (presumably b/c the sstable was still mmap'd.) |
| * Useful because there are times when we know GC has been invoked; also exposed as an mbean. |
| */ |
| public static void rescheduleFailedTasks() |
| { |
| Runnable task; |
| while ( null != (task = failedTasks.poll())) |
| ScheduledExecutors.nonPeriodicTasks.submit(task); |
| |
| // On Windows, snapshots cannot be deleted so long as a segment of the root element is memory-mapped in NTFS. |
| SnapshotDeletingTask.rescheduleFailedTasks(); |
| } |
| |
| /** for tests */ |
| @VisibleForTesting |
| public static void waitForDeletions() |
| { |
| Runnable runnable = new Runnable() |
| { |
| public void run() |
| { |
| } |
| }; |
| |
| FBUtilities.waitOnFuture(ScheduledExecutors.nonPeriodicTasks.schedule(runnable, 0, TimeUnit.MILLISECONDS)); |
| } |
| |
| @VisibleForTesting |
| public static void pauseDeletions(boolean stop) |
| { |
| blocker.block(stop); |
| } |
| } |
| |