/**
* 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.db;
import java.io.DataOutput;
import java.io.File;
import java.io.IOException;
import java.lang.management.ManagementFactory;
import java.nio.ByteBuffer;
import java.security.MessageDigest;
import java.util.*;
import java.util.Map.Entry;
import java.util.concurrent.*;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
import javax.management.MBeanServer;
import javax.management.ObjectName;
import org.apache.commons.collections.PredicateUtils;
import org.apache.commons.collections.iterators.FilterIterator;
import org.apache.commons.lang.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.cassandra.concurrent.DebuggableThreadPoolExecutor;
import org.apache.cassandra.config.DatabaseDescriptor;
import org.apache.cassandra.dht.Range;
import org.apache.cassandra.io.AbstractCompactedRow;
import org.apache.cassandra.io.CompactionIterator;
import org.apache.cassandra.io.ICompactionInfo;
import org.apache.cassandra.io.sstable.*;
import org.apache.cassandra.io.util.FileUtils;
import org.apache.cassandra.service.AntiEntropyService;
import org.apache.cassandra.service.StorageService;
import org.apache.cassandra.utils.Pair;
import org.cliffc.high_scale_lib.NonBlockingHashMap;
public class CompactionManager implements CompactionManagerMBean
{
public static final String MBEAN_OBJECT_NAME = "org.apache.cassandra.db:type=CompactionManager";
private static final Logger logger = LoggerFactory.getLogger(CompactionManager.class);
public static final CompactionManager instance;
private final ReentrantLock compactionLock = new ReentrantLock();
// todo: should provide a way to unlock in mbean?
static
{
instance = new CompactionManager();
MBeanServer mbs = ManagementFactory.getPlatformMBeanServer();
try
{
mbs.registerMBean(instance, new ObjectName(MBEAN_OBJECT_NAME));
}
catch (Exception e)
{
throw new RuntimeException(e);
}
}
private CompactionExecutor executor = new CompactionExecutor();
private Map<ColumnFamilyStore, Integer> estimatedCompactions = new NonBlockingHashMap<ColumnFamilyStore, Integer>();
public Lock getCompactionLock()
{
return compactionLock;
}
/**
* Call this whenever a compaction might be needed on the given columnfamily.
* It's okay to over-call (within reason) since the compactions are single-threaded,
* and if a call is unnecessary, it will just be no-oped in the bucketing phase.
*/
public Future<Integer> submitMinorIfNeeded(final ColumnFamilyStore cfs)
{
Callable<Integer> callable = new Callable<Integer>()
{
public Integer call() throws IOException
{
compactionLock.lock();
try
{
if (cfs.isInvalid())
return 0;
Integer minThreshold = cfs.getMinimumCompactionThreshold();
Integer maxThreshold = cfs.getMaximumCompactionThreshold();
if (minThreshold == 0 || maxThreshold == 0)
{
logger.debug("Compaction is currently disabled.");
return 0;
}
logger.debug("Checking to see if compaction of " + cfs.columnFamily + " would be useful");
Set<List<SSTableReader>> buckets = getBuckets(convertSSTablesToPairs(cfs.getSSTables()), 50L * 1024L * 1024L);
updateEstimateFor(cfs, buckets);
for (List<SSTableReader> sstables : buckets)
{
if (sstables.size() >= minThreshold)
{
// if we have too many to compact all at once, compact older ones first -- this avoids
// re-compacting files we just created.
Collections.sort(sstables);
int gcBefore = cfs.isIndex()
? Integer.MAX_VALUE
: (int) (System.currentTimeMillis() / 1000) - cfs.metadata.getGcGraceSeconds();
return doCompaction(cfs,
sstables.subList(0, Math.min(sstables.size(), maxThreshold)),
gcBefore);
}
}
}
finally
{
compactionLock.unlock();
}
return 0;
}
};
return executor.submit(callable);
}
private void updateEstimateFor(ColumnFamilyStore cfs, Set<List<SSTableReader>> buckets)
{
Integer minThreshold = cfs.getMinimumCompactionThreshold();
Integer maxThreshold = cfs.getMaximumCompactionThreshold();
if (minThreshold > 0 && maxThreshold > 0)
{
int n = 0;
for (List<SSTableReader> sstables : buckets)
{
if (sstables.size() >= minThreshold)
{
n += Math.ceil((double)sstables.size() / maxThreshold);
}
}
estimatedCompactions.put(cfs, n);
}
else
{
logger.debug("Compaction is currently disabled.");
}
}
public void performCleanup(final ColumnFamilyStore cfStore) throws InterruptedException, ExecutionException
{
Callable<Object> runnable = new Callable<Object>()
{
public Object call() throws IOException
{
compactionLock.lock();
try
{
if (!cfStore.isInvalid())
doCleanupCompaction(cfStore);
return this;
}
finally
{
compactionLock.unlock();
}
}
};
executor.submit(runnable).get();
}
public void performMajor(final ColumnFamilyStore cfStore) throws InterruptedException, ExecutionException
{
submitMajor(cfStore, 0, (int) (System.currentTimeMillis() / 1000) - cfStore.metadata.getGcGraceSeconds()).get();
}
public Future<Object> submitMajor(final ColumnFamilyStore cfStore, final long skip, final int gcBefore)
{
Callable<Object> callable = new Callable<Object>()
{
public Object call() throws IOException
{
compactionLock.lock();
try
{
if (cfStore.isInvalid())
return this;
Collection<SSTableReader> sstables;
if (skip > 0)
{
sstables = new ArrayList<SSTableReader>();
for (SSTableReader sstable : cfStore.getSSTables())
{
if (sstable.length() < skip * 1024L * 1024L * 1024L)
{
sstables.add(sstable);
}
}
}
else
{
sstables = cfStore.getSSTables();
}
doCompaction(cfStore, sstables, gcBefore);
return this;
}
finally
{
compactionLock.unlock();
}
}
};
return executor.submit(callable);
}
public Future<Object> submitValidation(final ColumnFamilyStore cfStore, final AntiEntropyService.Validator validator)
{
Callable<Object> callable = new Callable<Object>()
{
public Object call() throws IOException
{
compactionLock.lock();
try
{
if (!cfStore.isInvalid())
doValidationCompaction(cfStore, validator);
return this;
}
finally
{
compactionLock.unlock();
}
}
};
return executor.submit(callable);
}
/* Used in tests. */
public void disableAutoCompaction()
{
for (String ksname : DatabaseDescriptor.getNonSystemTables())
{
Table ks = Table.open(ksname);
for (ColumnFamilyStore cfs : ks.columnFamilyStores.values())
cfs.disableAutoCompaction();
}
}
/**
* For internal use and testing only. The rest of the system should go through the submit* methods,
* which are properly serialized.
*/
int doCompaction(ColumnFamilyStore cfs, Collection<SSTableReader> sstables, int gcBefore) throws IOException
{
// The collection of sstables passed may be empty (but not null); even if
// it is not empty, it may compact down to nothing if all rows are deleted.
Table table = cfs.table;
if (DatabaseDescriptor.isSnapshotBeforeCompaction())
table.snapshot("compact-" + cfs.columnFamily);
logger.info("Compacting [" + StringUtils.join(sstables, ",") + "]");
String compactionFileLocation = table.getDataFileLocation(cfs.getExpectedCompactedFileSize(sstables));
// If the compaction file path is null that means we have no space left for this compaction.
// try again w/o the largest one.
List<SSTableReader> smallerSSTables = new ArrayList<SSTableReader>(sstables);
while (compactionFileLocation == null && smallerSSTables.size() > 1)
{
logger.warn("insufficient space to compact all requested files " + StringUtils.join(smallerSSTables, ", "));
smallerSSTables.remove(cfs.getMaxSizeFile(smallerSSTables));
compactionFileLocation = table.getDataFileLocation(cfs.getExpectedCompactedFileSize(smallerSSTables));
}
if (compactionFileLocation == null)
{
logger.error("insufficient space to compact even the two smallest files, aborting");
return 0;
}
sstables = smallerSSTables;
// new sstables from flush can be added during a compaction, but only the compaction can remove them,
// so in our single-threaded compaction world this is a valid way of determining if we're compacting
// all the sstables (that existed when we started)
boolean major = cfs.isCompleteSSTables(sstables);
long startTime = System.currentTimeMillis();
long totalkeysWritten = 0;
// TODO the int cast here is potentially buggy
int expectedBloomFilterSize = Math.max(DatabaseDescriptor.getIndexInterval(), (int)SSTableReader.getApproximateKeyCount(sstables));
if (logger.isDebugEnabled())
logger.debug("Expected bloom filter size : " + expectedBloomFilterSize);
SSTableWriter writer;
CompactionIterator ci = new CompactionIterator(cfs, sstables, gcBefore, major); // retain a handle so we can call close()
Iterator<AbstractCompactedRow> nni = new FilterIterator(ci, PredicateUtils.notNullPredicate());
executor.beginCompaction(cfs, ci);
Map<DecoratedKey, Long> cachedKeys = new HashMap<DecoratedKey, Long>();
try
{
if (!nni.hasNext())
{
// don't mark compacted in the finally block, since if there _is_ nondeleted data,
// we need to sync it (via closeAndOpen) first, so there is no period during which
// a crash could cause data loss.
cfs.markCompacted(sstables);
return 0;
}
String newFilename = new File(cfs.getTempSSTablePath(compactionFileLocation)).getAbsolutePath();
writer = new SSTableWriter(newFilename, expectedBloomFilterSize, cfs.metadata, cfs.partitioner);
while (nni.hasNext())
{
AbstractCompactedRow row = nni.next();
long position = writer.append(row);
totalkeysWritten++;
for (SSTableReader sstable : sstables)
{
if (sstable.getCachedPosition(row.key) != null)
{
cachedKeys.put(row.key, position);
break;
}
}
}
}
finally
{
ci.close();
}
SSTableReader ssTable = writer.closeAndOpenReader(getMaxDataAge(sstables));
cfs.replaceCompactedSSTables(sstables, Arrays.asList(ssTable));
for (Entry<DecoratedKey, Long> entry : cachedKeys.entrySet())
ssTable.cacheKey(entry.getKey(), entry.getValue());
submitMinorIfNeeded(cfs);
long dTime = System.currentTimeMillis() - startTime;
long startsize = SSTable.getTotalBytes(sstables);
long endsize = ssTable.length();
double ratio = (double)endsize / (double)startsize;
logger.info(String.format("Compacted to %s. %,d to %,d (~%d%% of original) bytes for %,d keys. Time: %,dms.",
writer.getFilename(), startsize, endsize, (int) (ratio * 100), totalkeysWritten, dTime));
return sstables.size();
}
private static long getMaxDataAge(Collection<SSTableReader> sstables)
{
long max = 0;
for (SSTableReader sstable : sstables)
{
if (sstable.maxDataAge > max)
max = sstable.maxDataAge;
}
return max;
}
/**
* This function goes over each file and removes the keys that the node is not responsible for
* and only keeps keys that this node is responsible for.
*
* @throws IOException
*/
private void doCleanupCompaction(ColumnFamilyStore cfs) throws IOException
{
assert !cfs.isIndex();
Table table = cfs.table;
Collection<Range> ranges = StorageService.instance.getLocalRanges(table.name);
for (SSTableReader sstable : cfs.getSSTables())
{
logger.info("Cleaning up " + sstable);
// Calculate the expected compacted filesize
long expectedRangeFileSize = cfs.getExpectedCompactedFileSize(Arrays.asList(sstable)) / 2;
String compactionFileLocation = table.getDataFileLocation(expectedRangeFileSize);
if (compactionFileLocation == null)
throw new UnsupportedOperationException("disk full");
long startTime = System.currentTimeMillis();
long totalkeysWritten = 0;
int expectedBloomFilterSize = Math.max(DatabaseDescriptor.getIndexInterval(),
(int)(SSTableReader.getApproximateKeyCount(Arrays.asList(sstable)) / 2));
if (logger.isDebugEnabled())
logger.debug("Expected bloom filter size : " + expectedBloomFilterSize);
SSTableWriter writer = null;
SSTableScanner scanner = sstable.getScanner(CompactionIterator.FILE_BUFFER_SIZE);
SortedSet<ByteBuffer> indexedColumns = cfs.getIndexedColumns();
executor.beginCompaction(cfs, new CleanupInfo(sstable, scanner));
try
{
while (scanner.hasNext())
{
SSTableIdentityIterator row = (SSTableIdentityIterator) scanner.next();
if (Range.isTokenInRanges(row.getKey().token, ranges))
{
writer = maybeCreateWriter(cfs, compactionFileLocation, expectedBloomFilterSize, writer);
writer.append(new EchoedRow(row));
totalkeysWritten++;
}
else
{
while (row.hasNext())
{
IColumn column = row.next();
if (indexedColumns.contains(column.name()))
Table.cleanupIndexEntry(cfs, row.getKey().key, column);
}
}
}
}
finally
{
scanner.close();
}
List<SSTableReader> results = new ArrayList<SSTableReader>();
if (writer != null)
{
SSTableReader newSstable = writer.closeAndOpenReader(sstable.maxDataAge);
results.add(newSstable);
String format = "Cleaned up to %s. %,d to %,d (~%d%% of original) bytes for %,d keys. Time: %,dms.";
long dTime = System.currentTimeMillis() - startTime;
long startsize = sstable.length();
long endsize = newSstable.length();
double ratio = (double)endsize / (double)startsize;
logger.info(String.format(format, writer.getFilename(), startsize, endsize, (int)(ratio*100), totalkeysWritten, dTime));
}
// flush to ensure we don't lose the tombstones on a restart, since they are not commitlog'd
for (ByteBuffer columnName : cfs.getIndexedColumns())
{
try
{
cfs.getIndexedColumnFamilyStore(columnName).forceBlockingFlush();
}
catch (ExecutionException e)
{
throw new RuntimeException(e);
}
catch (InterruptedException e)
{
throw new AssertionError(e);
}
}
cfs.replaceCompactedSSTables(Arrays.asList(sstable), results);
}
}
private SSTableWriter maybeCreateWriter(ColumnFamilyStore cfs, String compactionFileLocation, int expectedBloomFilterSize, SSTableWriter writer)
throws IOException
{
if (writer == null)
{
FileUtils.createDirectory(compactionFileLocation);
String newFilename = new File(cfs.getTempSSTablePath(compactionFileLocation)).getAbsolutePath();
writer = new SSTableWriter(newFilename, expectedBloomFilterSize, cfs.metadata, cfs.partitioner);
}
return writer;
}
/**
* Performs a readonly "compaction" of all sstables in order to validate complete rows,
* but without writing the merge result
*/
private void doValidationCompaction(ColumnFamilyStore cfs, AntiEntropyService.Validator validator) throws IOException
{
// flush first so everyone is validating data that is as similar as possible
try
{
StorageService.instance.forceTableFlush(cfs.table.name, cfs.getColumnFamilyName());
}
catch (ExecutionException e)
{
throw new IOException(e);
}
catch (InterruptedException e)
{
throw new AssertionError(e);
}
CompactionIterator ci = new ValidationCompactionIterator(cfs);
executor.beginCompaction(cfs, ci);
try
{
Iterator<AbstractCompactedRow> nni = new FilterIterator(ci, PredicateUtils.notNullPredicate());
// validate the CF as we iterate over it
validator.prepare(cfs);
while (nni.hasNext())
{
AbstractCompactedRow row = nni.next();
validator.add(row);
}
validator.complete();
}
finally
{
ci.close();
}
}
/*
* Group files of similar size into buckets.
*/
static <T> Set<List<T>> getBuckets(Collection<Pair<T, Long>> files, long min)
{
// Sort the list in order to get deterministic results during the grouping below
List<Pair<T, Long>> sortedFiles = new ArrayList<Pair<T, Long>>(files);
Collections.sort(sortedFiles, new Comparator<Pair<T, Long>>()
{
public int compare(Pair<T, Long> p1, Pair<T, Long> p2)
{
return p1.right.compareTo(p2.right);
}
});
Map<List<T>, Long> buckets = new HashMap<List<T>, Long>();
for (Pair<T, Long> pair: sortedFiles)
{
long size = pair.right;
boolean bFound = false;
// look for a bucket containing similar-sized files:
// group in the same bucket if it's w/in 50% of the average for this bucket,
// or this file and the bucket are all considered "small" (less than `min`)
for (Entry<List<T>, Long> entry : buckets.entrySet())
{
List<T> bucket = entry.getKey();
long averageSize = entry.getValue();
if ((size > (averageSize / 2) && size < (3 * averageSize) / 2)
|| (size < min && averageSize < min))
{
// remove and re-add because adding changes the hash
buckets.remove(bucket);
long totalSize = bucket.size() * averageSize;
averageSize = (totalSize + size) / (bucket.size() + 1);
bucket.add(pair.left);
buckets.put(bucket, averageSize);
bFound = true;
break;
}
}
// no similar bucket found; put it in a new one
if (!bFound)
{
ArrayList<T> bucket = new ArrayList<T>();
bucket.add(pair.left);
buckets.put(bucket, size);
}
}
return buckets.keySet();
}
private static Collection<Pair<SSTableReader, Long>> convertSSTablesToPairs(Collection<SSTableReader> collection)
{
Collection<Pair<SSTableReader, Long>> tablePairs = new ArrayList<Pair<SSTableReader, Long>>();
for(SSTableReader table: collection)
{
tablePairs.add(new Pair<SSTableReader, Long>(table, table.length()));
}
return tablePairs;
}
public Future submitIndexBuild(final ColumnFamilyStore cfs, final Table.IndexBuilder builder)
{
Runnable runnable = new Runnable()
{
public void run()
{
compactionLock.lock();
try
{
if (cfs.isInvalid())
return;
executor.beginCompaction(cfs, builder);
builder.build();
}
finally
{
compactionLock.unlock();
}
}
};
// don't submit to the executor if the compaction lock is held by the current thread. Instead return a simple
// future that will be immediately immediately get()ed and executed. Happens during a migration, which locks
// the compaction thread and then reinitializes a ColumnFamilyStore. Under normal circumstances, CFS spawns
// index jobs to the compaction manager (this) and blocks on them.
if (compactionLock.isHeldByCurrentThread())
return new SimpleFuture(runnable);
else
return executor.submit(runnable);
}
public Future<SSTableReader> submitSSTableBuild(Descriptor desc)
{
// invalid descriptions due to missing or dropped CFS are handled by SSTW and StreamInSession.
final SSTableWriter.Builder builder = SSTableWriter.createBuilder(desc);
Callable<SSTableReader> callable = new Callable<SSTableReader>()
{
public SSTableReader call() throws IOException
{
compactionLock.lock();
try
{
executor.beginCompaction(builder.cfs, builder);
return builder.build();
}
finally
{
compactionLock.unlock();
}
}
};
return executor.submit(callable);
}
private static class ValidationCompactionIterator extends CompactionIterator
{
public ValidationCompactionIterator(ColumnFamilyStore cfs) throws IOException
{
super(cfs, cfs.getSSTables(), (int) (System.currentTimeMillis() / 1000) - cfs.metadata.getGcGraceSeconds(), true);
}
@Override
public String getTaskType()
{
return "Validation";
}
}
public void checkAllColumnFamilies() throws IOException
{
// perform estimates
for (final ColumnFamilyStore cfs : ColumnFamilyStore.all())
{
Runnable runnable = new Runnable()
{
public void run ()
{
logger.debug("Estimating compactions for " + cfs.columnFamily);
final Set<List<SSTableReader>> buckets = getBuckets(convertSSTablesToPairs(cfs.getSSTables()), 50L * 1024L * 1024L);
updateEstimateFor(cfs, buckets);
}
};
executor.submit(runnable);
}
// actually schedule compactions. done in a second pass so all the estimates occur before we
// bog down the executor in actual compactions.
for (ColumnFamilyStore cfs : ColumnFamilyStore.all())
{
submitMinorIfNeeded(cfs);
}
}
private static class CompactionExecutor extends DebuggableThreadPoolExecutor
{
private volatile ColumnFamilyStore cfs;
private volatile ICompactionInfo ci;
public CompactionExecutor()
{
super("CompactionExecutor", DatabaseDescriptor.getCompactionThreadPriority());
}
@Override
public void afterExecute(Runnable r, Throwable t)
{
super.afterExecute(r, t);
cfs = null;
ci = null;
}
void beginCompaction(ColumnFamilyStore cfs, ICompactionInfo ci)
{
this.cfs = cfs;
this.ci = ci;
}
public String getColumnFamilyName()
{
return cfs == null ? null : cfs.getColumnFamilyName();
}
public Long getBytesTotal()
{
return ci == null ? null : ci.getTotalBytes();
}
public Long getBytesCompleted()
{
return ci == null ? null : ci.getBytesRead();
}
public String getType()
{
return ci == null ? null : ci.getTaskType();
}
}
public String getColumnFamilyInProgress()
{
return executor.getColumnFamilyName();
}
public Long getBytesTotalInProgress()
{
return executor.getBytesTotal();
}
public Long getBytesCompacted()
{
return executor.getBytesCompleted();
}
public String getCompactionType()
{
return executor.getType();
}
public int getPendingTasks()
{
int n = 0;
for (Integer i : estimatedCompactions.values())
n += i;
return (int) (executor.getTaskCount() - executor.getCompletedTaskCount()) + n;
}
public long getCompletedTasks()
{
return executor.getCompletedTaskCount();
}
private static class SimpleFuture implements Future
{
private Runnable runnable;
private SimpleFuture(Runnable r)
{
runnable = r;
}
public boolean cancel(boolean mayInterruptIfRunning)
{
throw new IllegalStateException("May not call SimpleFuture.cancel()");
}
public boolean isCancelled()
{
return false;
}
public boolean isDone()
{
return runnable == null;
}
public Object get() throws InterruptedException, ExecutionException
{
runnable.run();
runnable = null;
return runnable;
}
public Object get(long timeout, TimeUnit unit) throws InterruptedException, ExecutionException, TimeoutException
{
throw new IllegalStateException("May not call SimpleFuture.get(long, TimeUnit)");
}
}
private static class EchoedRow extends AbstractCompactedRow
{
private final SSTableIdentityIterator row;
public EchoedRow(SSTableIdentityIterator row)
{
super(row.getKey());
this.row = row;
}
public void write(DataOutput out) throws IOException
{
out.writeLong(row.dataSize);
row.echoData(out);
}
public void update(MessageDigest digest)
{
// EchoedRow is not used in anti-entropy validation
throw new UnsupportedOperationException();
}
public boolean isEmpty()
{
return !row.hasNext();
}
public int columnCount()
{
return row.columnCount;
}
}
private static class CleanupInfo implements ICompactionInfo
{
private final SSTableReader sstable;
private final SSTableScanner scanner;
public CleanupInfo(SSTableReader sstable, SSTableScanner scanner)
{
this.sstable = sstable;
this.scanner = scanner;
}
public long getTotalBytes()
{
return scanner.getFileLength();
}
public long getBytesRead()
{
return scanner.getFilePointer();
}
public String getTaskType()
{
return "Cleanup of " + sstable.getColumnFamilyName();
}
}
}