/*
* 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.*;
import java.nio.ByteBuffer;
import java.util.*;
import java.util.concurrent.*;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.atomic.AtomicLong;
import com.clearspring.analytics.stream.cardinality.CardinalityMergeException;
import com.clearspring.analytics.stream.cardinality.ICardinality;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.base.Predicate;
import com.google.common.collect.Iterators;
import com.google.common.collect.Ordering;
import com.google.common.primitives.Longs;
import com.google.common.util.concurrent.RateLimiter;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.cassandra.cache.InstrumentingCache;
import org.apache.cassandra.cache.KeyCacheKey;
import org.apache.cassandra.concurrent.DebuggableThreadPoolExecutor;
import org.apache.cassandra.config.*;
import org.apache.cassandra.db.*;
import org.apache.cassandra.db.columniterator.OnDiskAtomIterator;
import org.apache.cassandra.db.commitlog.ReplayPosition;
import org.apache.cassandra.db.compaction.ICompactionScanner;
import org.apache.cassandra.db.index.SecondaryIndex;
import org.apache.cassandra.dht.*;
import org.apache.cassandra.io.compress.CompressedRandomAccessReader;
import org.apache.cassandra.io.compress.CompressedThrottledReader;
import org.apache.cassandra.io.compress.CompressionMetadata;
import org.apache.cassandra.io.sstable.metadata.*;
import org.apache.cassandra.io.util.*;
import org.apache.cassandra.metrics.RestorableMeter;
import org.apache.cassandra.service.CacheService;
import org.apache.cassandra.service.StorageService;
import org.apache.cassandra.tracing.Tracing;
import org.apache.cassandra.utils.*;
import static org.apache.cassandra.db.Directories.SECONDARY_INDEX_NAME_SEPARATOR;
/**
* SSTableReaders are open()ed by Keyspace.onStart; after that they are created by SSTableWriter.renameAndOpen.
* Do not re-call open() on existing SSTable files; use the references kept by ColumnFamilyStore post-start instead.
*/
public class SSTableReader extends SSTable implements Closeable
{
private static final Logger logger = LoggerFactory.getLogger(SSTableReader.class);
private static final ScheduledThreadPoolExecutor syncExecutor = new ScheduledThreadPoolExecutor(1);
private static final RateLimiter meterSyncThrottle = RateLimiter.create(100.0);
public static final Comparator<SSTableReader> maxTimestampComparator = new Comparator<SSTableReader>()
{
public int compare(SSTableReader o1, SSTableReader o2)
{
long ts1 = o1.getMaxTimestamp();
long ts2 = o2.getMaxTimestamp();
return (ts1 > ts2 ? -1 : (ts1 == ts2 ? 0 : 1));
}
};
public static final Comparator<SSTableReader> sstableComparator = new Comparator<SSTableReader>()
{
public int compare(SSTableReader o1, SSTableReader o2)
{
return o1.first.compareTo(o2.first);
}
};
public static final Ordering<SSTableReader> sstableOrdering = Ordering.from(sstableComparator);
/**
* maxDataAge is a timestamp in local server time (e.g. System.currentTimeMilli) which represents an upper bound
* to the newest piece of data stored in the sstable. In other words, this sstable does not contain items created
* later than maxDataAge.
*
* The field is not serialized to disk, so relying on it for more than what truncate does is not advised.
*
* When a new sstable is flushed, maxDataAge is set to the time of creation.
* When a sstable is created from compaction, maxDataAge is set to max of all merged sstables.
*
* The age is in milliseconds since epoc and is local to this host.
*/
public final long maxDataAge;
// indexfile and datafile: might be null before a call to load()
private SegmentedFile ifile;
private SegmentedFile dfile;
private IndexSummary indexSummary;
private IFilter bf;
private InstrumentingCache<KeyCacheKey, RowIndexEntry> keyCache;
private final BloomFilterTracker bloomFilterTracker = new BloomFilterTracker();
private final AtomicInteger references = new AtomicInteger(1);
// technically isCompacted is not necessary since it should never be unreferenced unless it is also compacted,
// but it seems like a good extra layer of protection against reference counting bugs to not delete data based on that alone
private final AtomicBoolean isCompacted = new AtomicBoolean(false);
private final AtomicBoolean isSuspect = new AtomicBoolean(false);
private final AtomicBoolean isReplaced = new AtomicBoolean(false);
private final SSTableDeletingTask deletingTask;
// not final since we need to be able to change level on a file.
private volatile StatsMetadata sstableMetadata;
private final AtomicLong keyCacheHit = new AtomicLong(0);
private final AtomicLong keyCacheRequest = new AtomicLong(0);
@VisibleForTesting
public RestorableMeter readMeter;
private ScheduledFuture readMeterSyncFuture;
/**
* Calculate approximate key count.
* If cardinality estimator is available on all given sstables, then this method use them to estimate
* key count.
* If not, then this uses index summaries.
*
* @param sstables SSTables to calculate key count
* @return estimated key count
*/
public static long getApproximateKeyCount(Collection<SSTableReader> sstables)
{
long count = -1;
// check if cardinality estimator is available for all SSTables
boolean cardinalityAvailable = !sstables.isEmpty() && Iterators.all(sstables.iterator(), new Predicate<SSTableReader>()
{
public boolean apply(SSTableReader sstable)
{
return sstable.descriptor.version.newStatsFile;
}
});
// if it is, load them to estimate key count
if (cardinalityAvailable)
{
boolean failed = false;
ICardinality cardinality = null;
for (SSTableReader sstable : sstables)
{
try
{
CompactionMetadata metadata = (CompactionMetadata) sstable.descriptor.getMetadataSerializer().deserialize(sstable.descriptor, MetadataType.COMPACTION);
if (cardinality == null)
cardinality = metadata.cardinalityEstimator;
else
cardinality = cardinality.merge(metadata.cardinalityEstimator);
}
catch (IOException e)
{
logger.warn("Reading cardinality from Statistics.db failed.", e);
failed = true;
break;
}
catch (CardinalityMergeException e)
{
logger.warn("Cardinality merge failed.", e);
failed = true;
break;
}
}
if (cardinality != null && !failed)
count = cardinality.cardinality();
}
// if something went wrong above or cardinality is not available, calculate using index summary
if (count < 0)
{
for (SSTableReader sstable : sstables)
{
// using getMaxIndexSummarySize() lets us ignore the current sampling level
count += (sstable.getMaxIndexSummarySize() + 1) * sstable.indexSummary.getSamplingLevel();
}
}
return count;
}
public static SSTableReader open(Descriptor descriptor) throws IOException
{
CFMetaData metadata;
if (descriptor.cfname.contains(SECONDARY_INDEX_NAME_SEPARATOR))
{
int i = descriptor.cfname.indexOf(SECONDARY_INDEX_NAME_SEPARATOR);
String parentName = descriptor.cfname.substring(0, i);
CFMetaData parent = Schema.instance.getCFMetaData(descriptor.ksname, parentName);
ColumnDefinition def = parent.getColumnDefinitionForIndex(descriptor.cfname.substring(i + 1));
metadata = CFMetaData.newIndexMetadata(parent, def, SecondaryIndex.getIndexComparator(parent, def));
}
else
{
metadata = Schema.instance.getCFMetaData(descriptor.ksname, descriptor.cfname);
}
return open(descriptor, metadata);
}
public static SSTableReader open(Descriptor desc, CFMetaData metadata) throws IOException
{
IPartitioner p = desc.cfname.contains(SECONDARY_INDEX_NAME_SEPARATOR)
? new LocalPartitioner(metadata.getKeyValidator())
: StorageService.getPartitioner();
return open(desc, componentsFor(desc), metadata, p);
}
public static SSTableReader open(Descriptor descriptor, Set<Component> components, CFMetaData metadata, IPartitioner partitioner) throws IOException
{
return open(descriptor, components, metadata, partitioner, true);
}
public static SSTableReader openNoValidation(Descriptor descriptor, Set<Component> components, CFMetaData metadata) throws IOException
{
return open(descriptor, components, metadata, StorageService.getPartitioner(), false);
}
/**
* Open SSTable reader to be used in batch mode(such as sstableloader).
*
* @param descriptor
* @param components
* @param metadata
* @param partitioner
* @return opened SSTableReader
* @throws IOException
*/
public static SSTableReader openForBatch(Descriptor descriptor, Set<Component> components, CFMetaData metadata, IPartitioner partitioner) throws IOException
{
// Minimum components without which we can't do anything
assert components.contains(Component.DATA) : "Data component is missing for sstable" + descriptor;
assert components.contains(Component.PRIMARY_INDEX) : "Primary index component is missing for sstable " + descriptor;
Map<MetadataType, MetadataComponent> sstableMetadata = descriptor.getMetadataSerializer().deserialize(descriptor,
EnumSet.of(MetadataType.VALIDATION, MetadataType.STATS));
ValidationMetadata validationMetadata = (ValidationMetadata) sstableMetadata.get(MetadataType.VALIDATION);
StatsMetadata statsMetadata = (StatsMetadata) sstableMetadata.get(MetadataType.STATS);
// Check if sstable is created using same partitioner.
// Partitioner can be null, which indicates older version of sstable or no stats available.
// In that case, we skip the check.
String partitionerName = partitioner.getClass().getCanonicalName();
if (validationMetadata != null && !partitionerName.equals(validationMetadata.partitioner))
{
logger.error(String.format("Cannot open %s; partitioner %s does not match system partitioner %s. Note that the default partitioner starting with Cassandra 1.2 is Murmur3Partitioner, so you will need to edit that to match your old partitioner if upgrading.",
descriptor, validationMetadata.partitioner, partitionerName));
System.exit(1);
}
logger.info("Opening {} ({} bytes)", descriptor, new File(descriptor.filenameFor(Component.DATA)).length());
SSTableReader sstable = new SSTableReader(descriptor,
components,
metadata,
partitioner,
System.currentTimeMillis(),
statsMetadata);
// special implementation of load to use non-pooled SegmentedFile builders
SegmentedFile.Builder ibuilder = new BufferedSegmentedFile.Builder();
SegmentedFile.Builder dbuilder = sstable.compression
? new CompressedSegmentedFile.Builder()
: new BufferedSegmentedFile.Builder();
if (!sstable.loadSummary(ibuilder, dbuilder))
sstable.buildSummary(false, ibuilder, dbuilder, false, Downsampling.BASE_SAMPLING_LEVEL);
sstable.ifile = ibuilder.complete(sstable.descriptor.filenameFor(Component.PRIMARY_INDEX));
sstable.dfile = dbuilder.complete(sstable.descriptor.filenameFor(Component.DATA));
sstable.bf = FilterFactory.AlwaysPresent;
return sstable;
}
private static SSTableReader open(Descriptor descriptor,
Set<Component> components,
CFMetaData metadata,
IPartitioner partitioner,
boolean validate) throws IOException
{
// Minimum components without which we can't do anything
assert components.contains(Component.DATA) : "Data component is missing for sstable" + descriptor;
assert components.contains(Component.PRIMARY_INDEX) : "Primary index component is missing for sstable " + descriptor;
Map<MetadataType, MetadataComponent> sstableMetadata = descriptor.getMetadataSerializer().deserialize(descriptor,
EnumSet.of(MetadataType.VALIDATION, MetadataType.STATS));
ValidationMetadata validationMetadata = (ValidationMetadata) sstableMetadata.get(MetadataType.VALIDATION);
StatsMetadata statsMetadata = (StatsMetadata) sstableMetadata.get(MetadataType.STATS);
// Check if sstable is created using same partitioner.
// Partitioner can be null, which indicates older version of sstable or no stats available.
// In that case, we skip the check.
String partitionerName = partitioner.getClass().getCanonicalName();
if (validationMetadata != null && !partitionerName.equals(validationMetadata.partitioner))
{
logger.error(String.format("Cannot open %s; partitioner %s does not match system partitioner %s. Note that the default partitioner starting with Cassandra 1.2 is Murmur3Partitioner, so you will need to edit that to match your old partitioner if upgrading.",
descriptor, validationMetadata.partitioner, partitionerName));
System.exit(1);
}
logger.info("Opening {} ({} bytes)", descriptor, new File(descriptor.filenameFor(Component.DATA)).length());
SSTableReader sstable = new SSTableReader(descriptor,
components,
metadata,
partitioner,
System.currentTimeMillis(),
statsMetadata);
// load index and filter
long start = System.nanoTime();
sstable.load(validationMetadata);
logger.debug("INDEX LOAD TIME for {}: {} ms.", descriptor, TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - start));
if (validate)
sstable.validate();
if (sstable.getKeyCache() != null)
logger.debug("key cache contains {}/{} keys", sstable.getKeyCache().size(), sstable.getKeyCache().getCapacity());
return sstable;
}
public static void logOpenException(Descriptor descriptor, IOException e)
{
if (e instanceof FileNotFoundException)
logger.error("Missing sstable component in {}; skipped because of {}", descriptor, e.getMessage());
else
logger.error("Corrupt sstable {}; skipped", descriptor, e);
}
public static Collection<SSTableReader> openAll(Set<Map.Entry<Descriptor, Set<Component>>> entries,
final CFMetaData metadata,
final IPartitioner partitioner)
{
final Collection<SSTableReader> sstables = new LinkedBlockingQueue<>();
ExecutorService executor = DebuggableThreadPoolExecutor.createWithFixedPoolSize("SSTableBatchOpen", FBUtilities.getAvailableProcessors());
for (final Map.Entry<Descriptor, Set<Component>> entry : entries)
{
Runnable runnable = new Runnable()
{
public void run()
{
SSTableReader sstable;
try
{
sstable = open(entry.getKey(), entry.getValue(), metadata, partitioner);
}
catch (IOException ex)
{
logger.error("Corrupt sstable {}; skipped", entry, ex);
return;
}
sstables.add(sstable);
}
};
executor.submit(runnable);
}
executor.shutdown();
try
{
executor.awaitTermination(7, TimeUnit.DAYS);
}
catch (InterruptedException e)
{
throw new AssertionError(e);
}
return sstables;
}
/**
* Open a RowIndexedReader which already has its state initialized (by SSTableWriter).
*/
static SSTableReader internalOpen(Descriptor desc,
Set<Component> components,
CFMetaData metadata,
IPartitioner partitioner,
SegmentedFile ifile,
SegmentedFile dfile,
IndexSummary isummary,
IFilter bf,
long maxDataAge,
StatsMetadata sstableMetadata)
{
assert desc != null && partitioner != null && ifile != null && dfile != null && isummary != null && bf != null && sstableMetadata != null;
return new SSTableReader(desc,
components,
metadata,
partitioner,
ifile, dfile,
isummary,
bf,
maxDataAge,
sstableMetadata);
}
private SSTableReader(final Descriptor desc,
Set<Component> components,
CFMetaData metadata,
IPartitioner partitioner,
long maxDataAge,
StatsMetadata sstableMetadata)
{
super(desc, components, metadata, partitioner);
this.sstableMetadata = sstableMetadata;
this.maxDataAge = maxDataAge;
deletingTask = new SSTableDeletingTask(this);
// Don't track read rates for tables in the system keyspace and don't bother trying to load or persist
// the read meter when in client mode
if (Keyspace.SYSTEM_KS.equals(desc.ksname) || Config.isClientMode())
{
readMeter = null;
readMeterSyncFuture = null;
return;
}
readMeter = SystemKeyspace.getSSTableReadMeter(desc.ksname, desc.cfname, desc.generation);
// sync the average read rate to system.sstable_activity every five minutes, starting one minute from now
readMeterSyncFuture = syncExecutor.scheduleAtFixedRate(new Runnable()
{
public void run()
{
if (!isCompacted.get())
{
meterSyncThrottle.acquire();
SystemKeyspace.persistSSTableReadMeter(desc.ksname, desc.cfname, desc.generation, readMeter);
}
}
}, 1, 5, TimeUnit.MINUTES);
}
private SSTableReader(Descriptor desc,
Set<Component> components,
CFMetaData metadata,
IPartitioner partitioner,
SegmentedFile ifile,
SegmentedFile dfile,
IndexSummary indexSummary,
IFilter bloomFilter,
long maxDataAge,
StatsMetadata sstableMetadata)
{
this(desc, components, metadata, partitioner, maxDataAge, sstableMetadata);
this.ifile = ifile;
this.dfile = dfile;
this.indexSummary = indexSummary;
this.bf = bloomFilter;
}
public static long getTotalBytes(Iterable<SSTableReader> sstables)
{
long sum = 0;
for (SSTableReader sstable : sstables)
{
sum += sstable.onDiskLength();
}
return sum;
}
/**
* Clean up all opened resources.
*
* @throws IOException
*/
public void close() throws IOException
{
if (readMeterSyncFuture != null)
readMeterSyncFuture.cancel(false);
// if this SSTR was replaced by a new SSTR with a different index summary, the two instances will share
// resources, so don't force unmapping, clear the FileCacheService entry, or close the BF
if (!isReplaced.get())
{
// Force finalizing mmapping if necessary
ifile.cleanup();
dfile.cleanup();
// close the BF so it can be opened later.
bf.close();
}
indexSummary.close();
}
public void setTrackedBy(DataTracker tracker)
{
deletingTask.setTracker(tracker);
// under normal operation we can do this at any time, but SSTR is also used outside C* proper,
// e.g. by BulkLoader, which does not initialize the cache. As a kludge, we set up the cache
// here when we know we're being wired into the rest of the server infrastructure.
keyCache = CacheService.instance.keyCache;
}
private void load(ValidationMetadata validation) throws IOException
{
if (metadata.getBloomFilterFpChance() == 1.0)
{
// bf is disabled.
load(false, true);
bf = FilterFactory.AlwaysPresent;
}
else if (!components.contains(Component.FILTER) || validation == null)
{
// bf is enabled, but filter component is missing.
load(true, true);
}
else if (descriptor.version.hasBloomFilterFPChance && validation.bloomFilterFPChance != metadata.getBloomFilterFpChance())
{
// bf fp chance in sstable metadata and it has changed since compaction.
load(true, true);
}
else
{
// bf is enabled, but fp chance isn't present in metadata (pre-ja) OR matches the currently configured value.
load(false, true);
loadBloomFilter();
}
}
/**
* Load bloom filter from Filter.db file.
*
* @throws IOException
*/
private void loadBloomFilter() throws IOException
{
DataInputStream stream = null;
try
{
stream = new DataInputStream(new BufferedInputStream(new FileInputStream(descriptor.filenameFor(Component.FILTER))));
bf = FilterFactory.deserialize(stream, true);
}
finally
{
FileUtils.closeQuietly(stream);
}
}
/**
* Loads ifile, dfile and indexSummary, and optionally recreates the bloom filter.
* @param saveSummaryIfCreated for bulk loading purposes, if the summary was absent and needed to be built, you can
* avoid persisting it to disk by setting this to false
*/
private void load(boolean recreateBloomFilter, boolean saveSummaryIfCreated) throws IOException
{
SegmentedFile.Builder ibuilder = SegmentedFile.getBuilder(DatabaseDescriptor.getIndexAccessMode());
SegmentedFile.Builder dbuilder = compression
? SegmentedFile.getCompressedBuilder()
: SegmentedFile.getBuilder(DatabaseDescriptor.getDiskAccessMode());
boolean summaryLoaded = loadSummary(ibuilder, dbuilder);
if (recreateBloomFilter || !summaryLoaded)
buildSummary(recreateBloomFilter, ibuilder, dbuilder, summaryLoaded, Downsampling.BASE_SAMPLING_LEVEL);
ifile = ibuilder.complete(descriptor.filenameFor(Component.PRIMARY_INDEX));
dfile = dbuilder.complete(descriptor.filenameFor(Component.DATA));
if (saveSummaryIfCreated && (recreateBloomFilter || !summaryLoaded)) // save summary information to disk
saveSummary(ibuilder, dbuilder);
}
/**
* Build index summary(and optionally bloom filter) by reading through Index.db file.
*
* @param recreateBloomFilter true if recreate bloom filter
* @param ibuilder
* @param dbuilder
* @param summaryLoaded true if index summary is already loaded and not need to build again
* @throws IOException
*/
private void buildSummary(boolean recreateBloomFilter, SegmentedFile.Builder ibuilder, SegmentedFile.Builder dbuilder, boolean summaryLoaded, int samplingLevel) throws IOException
{
// we read the positions in a BRAF so we don't have to worry about an entry spanning a mmap boundary.
RandomAccessReader primaryIndex = RandomAccessReader.open(new File(descriptor.filenameFor(Component.PRIMARY_INDEX)));
try
{
long indexSize = primaryIndex.length();
long histogramCount = sstableMetadata.estimatedRowSize.count();
long estimatedKeys = histogramCount > 0 && !sstableMetadata.estimatedRowSize.isOverflowed()
? histogramCount
: estimateRowsFromIndex(primaryIndex); // statistics is supposed to be optional
if (recreateBloomFilter)
bf = FilterFactory.getFilter(estimatedKeys, metadata.getBloomFilterFpChance(), true);
IndexSummaryBuilder summaryBuilder = null;
if (!summaryLoaded)
summaryBuilder = new IndexSummaryBuilder(estimatedKeys, metadata.getIndexInterval(), samplingLevel);
long indexPosition;
while ((indexPosition = primaryIndex.getFilePointer()) != indexSize)
{
ByteBuffer key = ByteBufferUtil.readWithShortLength(primaryIndex);
RowIndexEntry indexEntry = metadata.comparator.rowIndexEntrySerializer().deserialize(primaryIndex, descriptor.version);
DecoratedKey decoratedKey = partitioner.decorateKey(key);
if (first == null)
first = decoratedKey;
last = decoratedKey;
if (recreateBloomFilter)
bf.add(decoratedKey.key);
// if summary was already read from disk we don't want to re-populate it using primary index
if (!summaryLoaded)
{
summaryBuilder.maybeAddEntry(decoratedKey, indexPosition);
ibuilder.addPotentialBoundary(indexPosition);
dbuilder.addPotentialBoundary(indexEntry.position);
}
}
if (!summaryLoaded)
indexSummary = summaryBuilder.build(partitioner);
}
finally
{
FileUtils.closeQuietly(primaryIndex);
}
first = getMinimalKey(first);
last = getMinimalKey(last);
}
/**
* Load index summary from Summary.db file if it exists.
*
* if loaded index summary has different index interval from current value stored in schema,
* then Summary.db file will be deleted and this returns false to rebuild summary.
*
* @param ibuilder
* @param dbuilder
* @return true if index summary is loaded successfully from Summary.db file.
*/
public boolean loadSummary(SegmentedFile.Builder ibuilder, SegmentedFile.Builder dbuilder)
{
File summariesFile = new File(descriptor.filenameFor(Component.SUMMARY));
if (!descriptor.version.offHeapSummaries || !summariesFile.exists())
return false;
DataInputStream iStream = null;
try
{
iStream = new DataInputStream(new FileInputStream(summariesFile));
indexSummary = IndexSummary.serializer.deserialize(iStream, partitioner, descriptor.version.hasSamplingLevel, metadata.getIndexInterval());
first = partitioner.decorateKey(ByteBufferUtil.readWithLength(iStream));
last = partitioner.decorateKey(ByteBufferUtil.readWithLength(iStream));
ibuilder.deserializeBounds(iStream);
dbuilder.deserializeBounds(iStream);
}
catch (IOException e)
{
logger.debug("Cannot deserialize SSTable {} Summary: {}", toString(), e.getMessage());
// corrupted; delete it and fall back to creating a new summary
FileUtils.closeQuietly(iStream);
// delete it and fall back to creating a new summary
FileUtils.deleteWithConfirm(summariesFile);
return false;
}
finally
{
FileUtils.closeQuietly(iStream);
}
return true;
}
/**
* Save index summary to Summary.db file.
*
* @param ibuilder
* @param dbuilder
*/
public void saveSummary(SegmentedFile.Builder ibuilder, SegmentedFile.Builder dbuilder)
{
saveSummary(ibuilder, dbuilder, indexSummary);
}
private void saveSummary(SegmentedFile.Builder ibuilder, SegmentedFile.Builder dbuilder, IndexSummary summary)
{
File summariesFile = new File(descriptor.filenameFor(Component.SUMMARY));
if (summariesFile.exists())
FileUtils.deleteWithConfirm(summariesFile);
DataOutputStream oStream = null;
try
{
oStream = new DataOutputStream(new FileOutputStream(summariesFile));
IndexSummary.serializer.serialize(summary, oStream, descriptor.version.hasSamplingLevel);
ByteBufferUtil.writeWithLength(first.key, oStream);
ByteBufferUtil.writeWithLength(last.key, oStream);
ibuilder.serializeBounds(oStream);
dbuilder.serializeBounds(oStream);
}
catch (IOException e)
{
logger.debug("Cannot save SSTable Summary: ", e);
// corrupted hence delete it and let it load it now.
if (summariesFile.exists())
FileUtils.deleteWithConfirm(summariesFile);
}
finally
{
FileUtils.closeQuietly(oStream);
}
}
/**
* Returns a new SSTableReader with the same properties as this SSTableReader except that a new IndexSummary will
* be built at the target samplingLevel. This (original) SSTableReader instance will be marked as replaced, have
* its DeletingTask removed, and have its periodic read-meter sync task cancelled.
* @param samplingLevel the desired sampling level for the index summary on the new SSTableReader
* @return a new SSTableReader
* @throws IOException
*/
public SSTableReader cloneWithNewSummarySamplingLevel(int samplingLevel) throws IOException
{
IndexSummary newSummary;
if (samplingLevel < indexSummary.getSamplingLevel())
{
newSummary = IndexSummaryBuilder.downsample(indexSummary, samplingLevel, partitioner);
SegmentedFile.Builder ibuilder = SegmentedFile.getBuilder(DatabaseDescriptor.getIndexAccessMode());
SegmentedFile.Builder dbuilder = compression
? SegmentedFile.getCompressedBuilder()
: SegmentedFile.getBuilder(DatabaseDescriptor.getDiskAccessMode());
saveSummary(ibuilder, dbuilder, newSummary);
}
else if (samplingLevel > indexSummary.getSamplingLevel())
{
newSummary = upsampleSummary(samplingLevel);
}
else
{
throw new AssertionError("Attempted to clone SSTableReader with the same index summary sampling level");
}
markReplaced();
if (readMeterSyncFuture != null)
readMeterSyncFuture.cancel(false);
SSTableReader replacement = new SSTableReader(descriptor, components, metadata, partitioner, ifile, dfile, newSummary, bf, maxDataAge, sstableMetadata);
replacement.readMeter = this.readMeter;
replacement.first = this.first;
replacement.last = this.last;
return replacement;
}
private IndexSummary upsampleSummary(int newSamplingLevel) throws IOException
{
// we read the positions in a BRAF so we don't have to worry about an entry spanning a mmap boundary.
RandomAccessReader primaryIndex = RandomAccessReader.open(new File(descriptor.filenameFor(Component.PRIMARY_INDEX)));
try
{
long indexSize = primaryIndex.length();
IndexSummaryBuilder summaryBuilder = new IndexSummaryBuilder(estimatedKeys(), metadata.getIndexInterval(), newSamplingLevel);
long indexPosition;
while ((indexPosition = primaryIndex.getFilePointer()) != indexSize)
{
summaryBuilder.maybeAddEntry(partitioner.decorateKey(ByteBufferUtil.readWithShortLength(primaryIndex)), indexPosition);
RowIndexEntry.Serializer.skip(primaryIndex);
}
return summaryBuilder.build(partitioner);
}
finally
{
FileUtils.closeQuietly(primaryIndex);
}
}
public int getIndexSummarySamplingLevel()
{
return indexSummary.getSamplingLevel();
}
public long getIndexSummaryOffHeapSize()
{
return indexSummary.getOffHeapSize();
}
public void releaseSummary() throws IOException
{
indexSummary.close();
indexSummary = null;
}
private void validate()
{
if (this.first.compareTo(this.last) > 0)
throw new IllegalStateException(String.format("SSTable first key %s > last key %s", this.first, this.last));
}
/**
* Gets the position in the index file to start scanning to find the given key (at most indexInterval keys away,
* modulo downsampling of the index summary).
*/
public long getIndexScanPosition(RowPosition key)
{
return getIndexScanPositionFromBinarySearchResult(indexSummary.binarySearch(key), indexSummary);
}
public static long getIndexScanPositionFromBinarySearchResult(int binarySearchResult, IndexSummary referencedIndexSummary)
{
if (binarySearchResult == -1)
return -1;
else
return referencedIndexSummary.getPosition(getIndexSummaryIndexFromBinarySearchResult(binarySearchResult));
}
private static int getIndexSummaryIndexFromBinarySearchResult(int binarySearchResult)
{
if (binarySearchResult < 0)
{
// binary search gives us the first index _greater_ than the key searched for,
// i.e., its insertion position
int greaterThan = (binarySearchResult + 1) * -1;
if (greaterThan == 0)
return -1;
return greaterThan - 1;
}
else
{
return binarySearchResult;
}
}
/**
* Returns the compression metadata for this sstable.
* @throws IllegalStateException if the sstable is not compressed
*/
public CompressionMetadata getCompressionMetadata()
{
if (!compression)
throw new IllegalStateException(this + " is not compressed");
return ((ICompressedFile) dfile).getMetadata();
}
/**
* For testing purposes only.
*/
public void forceFilterFailures()
{
bf = FilterFactory.AlwaysPresent;
}
public IFilter getBloomFilter()
{
return bf;
}
public long getBloomFilterSerializedSize()
{
return bf.serializedSize();
}
/**
* @return An estimate of the number of keys in this SSTable.
*/
public long estimatedKeys()
{
return ((long) indexSummary.getMaxNumberOfEntries()) * indexSummary.getIndexInterval();
}
/**
* @param ranges
* @return An estimate of the number of keys for given ranges in this SSTable.
*/
public long estimatedKeysForRanges(Collection<Range<Token>> ranges)
{
long sampleKeyCount = 0;
List<Pair<Integer, Integer>> sampleIndexes = getSampleIndexesForRanges(indexSummary, ranges);
for (Pair<Integer, Integer> sampleIndexRange : sampleIndexes)
sampleKeyCount += (sampleIndexRange.right - sampleIndexRange.left + 1);
// adjust for the current sampling level
long estimatedKeys = sampleKeyCount * (Downsampling.BASE_SAMPLING_LEVEL * indexSummary.getIndexInterval()) / indexSummary.getSamplingLevel();
return Math.max(1, estimatedKeys);
}
/**
* Returns the number of entries in the IndexSummary. At full sampling, this is approximately 1/INDEX_INTERVALth of
* the keys in this SSTable.
*/
public int getIndexSummarySize()
{
return indexSummary.size();
}
/**
* Returns the approximate number of entries the IndexSummary would contain if it were at full sampling.
*/
public int getMaxIndexSummarySize()
{
return indexSummary.getMaxNumberOfEntries();
}
/**
* Returns the key for the index summary entry at `index`.
*/
public byte[] getIndexSummaryKey(int index)
{
return indexSummary.getKey(index);
}
private static List<Pair<Integer,Integer>> getSampleIndexesForRanges(IndexSummary summary, Collection<Range<Token>> ranges)
{
// use the index to determine a minimal section for each range
List<Pair<Integer,Integer>> positions = new ArrayList<>();
for (Range<Token> range : Range.normalize(ranges))
{
RowPosition leftPosition = range.left.maxKeyBound();
RowPosition rightPosition = range.right.maxKeyBound();
int left = summary.binarySearch(leftPosition);
if (left < 0)
left = (left + 1) * -1;
else
// left range are start exclusive
left = left + 1;
if (left == summary.size())
// left is past the end of the sampling
continue;
int right = Range.isWrapAround(range.left, range.right)
? summary.size() - 1
: summary.binarySearch(rightPosition);
if (right < 0)
{
// range are end inclusive so we use the previous index from what binarySearch give us
// since that will be the last index we will return
right = (right + 1) * -1;
if (right == 0)
// Means the first key is already stricly greater that the right bound
continue;
right--;
}
if (left > right)
// empty range
continue;
positions.add(Pair.create(left, right));
}
return positions;
}
public Iterable<DecoratedKey> getKeySamples(final Range<Token> range)
{
final List<Pair<Integer, Integer>> indexRanges = getSampleIndexesForRanges(indexSummary, Collections.singletonList(range));
if (indexRanges.isEmpty())
return Collections.emptyList();
return new Iterable<DecoratedKey>()
{
public Iterator<DecoratedKey> iterator()
{
return new Iterator<DecoratedKey>()
{
private Iterator<Pair<Integer, Integer>> rangeIter = indexRanges.iterator();
private Pair<Integer, Integer> current;
private int idx;
public boolean hasNext()
{
if (current == null || idx > current.right)
{
if (rangeIter.hasNext())
{
current = rangeIter.next();
idx = current.left;
return true;
}
return false;
}
return true;
}
public DecoratedKey next()
{
byte[] bytes = indexSummary.getKey(idx++);
return partitioner.decorateKey(ByteBuffer.wrap(bytes));
}
public void remove()
{
throw new UnsupportedOperationException();
}
};
}
};
}
/**
* Determine the minimal set of sections that can be extracted from this SSTable to cover the given ranges.
* @return A sorted list of (offset,end) pairs that cover the given ranges in the datafile for this SSTable.
*/
public List<Pair<Long,Long>> getPositionsForRanges(Collection<Range<Token>> ranges)
{
// use the index to determine a minimal section for each range
List<Pair<Long,Long>> positions = new ArrayList<>();
for (Range<Token> range : Range.normalize(ranges))
{
AbstractBounds<RowPosition> keyRange = range.toRowBounds();
RowIndexEntry idxLeft = getPosition(keyRange.left, Operator.GT);
long left = idxLeft == null ? -1 : idxLeft.position;
if (left == -1)
// left is past the end of the file
continue;
RowIndexEntry idxRight = getPosition(keyRange.right, Operator.GT);
long right = idxRight == null ? -1 : idxRight.position;
if (right == -1 || Range.isWrapAround(range.left, range.right))
// right is past the end of the file, or it wraps
right = uncompressedLength();
if (left == right)
// empty range
continue;
positions.add(Pair.create(left, right));
}
return positions;
}
public void cacheKey(DecoratedKey key, RowIndexEntry info)
{
CFMetaData.Caching caching = metadata.getCaching();
if (caching == CFMetaData.Caching.NONE
|| caching == CFMetaData.Caching.ROWS_ONLY
|| keyCache == null
|| keyCache.getCapacity() == 0)
{
return;
}
KeyCacheKey cacheKey = new KeyCacheKey(metadata.cfId, descriptor, key.key);
logger.trace("Adding cache entry for {} -> {}", cacheKey, info);
keyCache.put(cacheKey, info);
}
public void preheat(Map<DecoratedKey, RowIndexEntry> cachedKeys) throws IOException
{
RandomAccessFile f = new RandomAccessFile(getFilename(), "r");
try
{
int fd = CLibrary.getfd(f.getFD());
for (Map.Entry<DecoratedKey, RowIndexEntry> entry : cachedKeys.entrySet())
{
cacheKey(entry.getKey(), entry.getValue());
// add to the cache but don't do actual preheating if we have it disabled in the config
if (DatabaseDescriptor.shouldPreheatPageCache() && fd > 0)
CLibrary.preheatPage(fd, entry.getValue().position);
}
}
finally
{
FileUtils.closeQuietly(f);
}
}
public RowIndexEntry getCachedPosition(DecoratedKey key, boolean updateStats)
{
return getCachedPosition(new KeyCacheKey(metadata.cfId, descriptor, key.key), updateStats);
}
private RowIndexEntry getCachedPosition(KeyCacheKey unifiedKey, boolean updateStats)
{
if (keyCache != null && keyCache.getCapacity() > 0) {
if (updateStats)
{
RowIndexEntry cachedEntry = keyCache.get(unifiedKey);
keyCacheRequest.incrementAndGet();
if (cachedEntry != null)
keyCacheHit.incrementAndGet();
return cachedEntry;
}
else
{
return keyCache.getInternal(unifiedKey);
}
}
return null;
}
/**
* Get position updating key cache and stats.
* @see #getPosition(org.apache.cassandra.db.RowPosition, org.apache.cassandra.io.sstable.SSTableReader.Operator, boolean)
*/
public RowIndexEntry getPosition(RowPosition key, Operator op)
{
return getPosition(key, op, true);
}
/**
* @param key The key to apply as the rhs to the given Operator. A 'fake' key is allowed to
* allow key selection by token bounds but only if op != * EQ
* @param op The Operator defining matching keys: the nearest key to the target matching the operator wins.
* @param updateCacheAndStats true if updating stats and cache
* @return The index entry corresponding to the key, or null if the key is not present
*/
public RowIndexEntry getPosition(RowPosition key, Operator op, boolean updateCacheAndStats)
{
// first, check bloom filter
if (op == Operator.EQ)
{
assert key instanceof DecoratedKey; // EQ only make sense if the key is a valid row key
if (!bf.isPresent(((DecoratedKey)key).key))
{
Tracing.trace("Bloom filter allows skipping sstable {}", descriptor.generation);
return null;
}
}
// next, the key cache (only make sense for valid row key)
if ((op == Operator.EQ || op == Operator.GE) && (key instanceof DecoratedKey))
{
DecoratedKey decoratedKey = (DecoratedKey)key;
KeyCacheKey cacheKey = new KeyCacheKey(metadata.cfId, descriptor, decoratedKey.key);
RowIndexEntry cachedPosition = getCachedPosition(cacheKey, updateCacheAndStats);
if (cachedPosition != null)
{
Tracing.trace("Key cache hit for sstable {}", descriptor.generation);
return cachedPosition;
}
}
// check the smallest and greatest keys in the sstable to see if it can't be present
if (first.compareTo(key) > 0 || last.compareTo(key) < 0)
{
if (op == Operator.EQ && updateCacheAndStats)
bloomFilterTracker.addFalsePositive();
if (op.apply(1) < 0)
{
Tracing.trace("Check against min and max keys allows skipping sstable {}", descriptor.generation);
return null;
}
}
int binarySearchResult = indexSummary.binarySearch(key);
long sampledPosition = getIndexScanPositionFromBinarySearchResult(binarySearchResult, indexSummary);
int sampledIndex = getIndexSummaryIndexFromBinarySearchResult(binarySearchResult);
// if we matched the -1th position, we'll start at the first position
sampledPosition = sampledPosition == -1 ? 0 : sampledPosition;
int effectiveInterval = indexSummary.getEffectiveIndexIntervalAfterIndex(sampledIndex);
// scan the on-disk index, starting at the nearest sampled position.
// The check against IndexInterval is to be exit the loop in the EQ case when the key looked for is not present
// (bloom filter false positive). But note that for non-EQ cases, we might need to check the first key of the
// next index position because the searched key can be greater the last key of the index interval checked if it
// is lesser than the first key of next interval (and in that case we must return the position of the first key
// of the next interval).
int i = 0;
Iterator<FileDataInput> segments = ifile.iterator(sampledPosition);
while (segments.hasNext() && i <= effectiveInterval)
{
FileDataInput in = segments.next();
try
{
while (!in.isEOF() && i <= effectiveInterval)
{
i++;
ByteBuffer indexKey = ByteBufferUtil.readWithShortLength(in);
boolean opSatisfied; // did we find an appropriate position for the op requested
boolean exactMatch; // is the current position an exact match for the key, suitable for caching
// Compare raw keys if possible for performance, otherwise compare decorated keys.
if (op == Operator.EQ)
{
opSatisfied = exactMatch = indexKey.equals(((DecoratedKey) key).key);
}
else
{
DecoratedKey indexDecoratedKey = partitioner.decorateKey(indexKey);
int comparison = indexDecoratedKey.compareTo(key);
int v = op.apply(comparison);
opSatisfied = (v == 0);
exactMatch = (comparison == 0);
if (v < 0)
{
Tracing.trace("Partition index lookup allows skipping sstable {}", descriptor.generation);
return null;
}
}
if (opSatisfied)
{
// read data position from index entry
RowIndexEntry indexEntry = metadata.comparator.rowIndexEntrySerializer().deserialize(in, descriptor.version);
if (exactMatch && updateCacheAndStats)
{
assert key instanceof DecoratedKey; // key can be == to the index key only if it's a true row key
DecoratedKey decoratedKey = (DecoratedKey)key;
if (logger.isTraceEnabled())
{
// expensive sanity check! see CASSANDRA-4687
FileDataInput fdi = dfile.getSegment(indexEntry.position);
DecoratedKey keyInDisk = partitioner.decorateKey(ByteBufferUtil.readWithShortLength(fdi));
if (!keyInDisk.equals(key))
throw new AssertionError(String.format("%s != %s in %s", keyInDisk, key, fdi.getPath()));
fdi.close();
}
// store exact match for the key
cacheKey(decoratedKey, indexEntry);
}
if (op == Operator.EQ && updateCacheAndStats)
bloomFilterTracker.addTruePositive();
Tracing.trace("Partition index with {} entries found for sstable {}", indexEntry.columnsIndex().size(), descriptor.generation);
return indexEntry;
}
RowIndexEntry.Serializer.skip(in);
}
}
catch (IOException e)
{
markSuspect();
throw new CorruptSSTableException(e, in.getPath());
}
finally
{
FileUtils.closeQuietly(in);
}
}
if (op == Operator.EQ && updateCacheAndStats)
bloomFilterTracker.addFalsePositive();
Tracing.trace("Partition index lookup complete (bloom filter false positive) for sstable {}", descriptor.generation);
return null;
}
/**
* Finds and returns the first key beyond a given token in this SSTable or null if no such key exists.
*/
public DecoratedKey firstKeyBeyond(RowPosition token)
{
long sampledPosition = getIndexScanPosition(token);
if (sampledPosition == -1)
sampledPosition = 0;
Iterator<FileDataInput> segments = ifile.iterator(sampledPosition);
while (segments.hasNext())
{
FileDataInput in = segments.next();
try
{
while (!in.isEOF())
{
ByteBuffer indexKey = ByteBufferUtil.readWithShortLength(in);
DecoratedKey indexDecoratedKey = partitioner.decorateKey(indexKey);
if (indexDecoratedKey.compareTo(token) > 0)
return indexDecoratedKey;
RowIndexEntry.Serializer.skip(in);
}
}
catch (IOException e)
{
markSuspect();
throw new CorruptSSTableException(e, in.getPath());
}
finally
{
FileUtils.closeQuietly(in);
}
}
return null;
}
/**
* @return The length in bytes of the data for this SSTable. For
* compressed files, this is not the same thing as the on disk size (see
* onDiskLength())
*/
public long uncompressedLength()
{
return dfile.length;
}
/**
* @return The length in bytes of the on disk size for this SSTable. For
* compressed files, this is not the same thing as the data length (see
* length())
*/
public long onDiskLength()
{
return dfile.onDiskLength;
}
public void markReplaced()
{
boolean success = isReplaced.compareAndSet(false, true);
assert success : "Attempted to mark an SSTableReader as replaced more than once";
}
public boolean acquireReference()
{
while (true)
{
int n = references.get();
if (n <= 0)
return false;
if (references.compareAndSet(n, n + 1))
return true;
}
}
/**
* Release reference to this SSTableReader.
* If there is no one referring to this SSTable, and is marked as compacted,
* all resources are cleaned up and files are deleted eventually.
*/
public void releaseReference()
{
if (references.decrementAndGet() == 0)
{
FileUtils.closeQuietly(this);
// if this SSTR instance was replaced by another with a different index summary, let the new instance
// handle clearing the page cache and deleting the files
if (isCompacted.get())
{
assert !isReplaced.get();
/**
* Do the OS a favour and suggest (using fadvice call) that we
* don't want to see pages of this SSTable in memory anymore.
*
* NOTE: We can't use madvice in java because it requires the address of
* the mapping, so instead we always open a file and run fadvice(fd, 0, 0) on it
*/
dropPageCache();
deletingTask.schedule();
}
}
assert references.get() >= 0 : "Reference counter " + references.get() + " for " + dfile.path;
}
/**
* Mark the sstable as obsolete, i.e., compacted into newer sstables.
*
* When calling this function, the caller must ensure that the SSTableReader is not referenced anywhere
* except for threads holding a reference.
*
* @return true if the this is the first time the file was marked obsolete. Calling this
* multiple times is usually buggy (see exceptions in DataTracker.unmarkCompacting and removeOldSSTablesSize).
*/
public boolean markObsolete()
{
if (logger.isDebugEnabled())
logger.debug("Marking {} compacted", getFilename());
return !isCompacted.getAndSet(true);
}
public void markSuspect()
{
if (logger.isDebugEnabled())
logger.debug("Marking {} as a suspect for blacklisting.", getFilename());
isSuspect.getAndSet(true);
}
public boolean isMarkedSuspect()
{
return isSuspect.get();
}
/**
*
* @param dataRange filter to use when reading the columns
* @return A Scanner for seeking over the rows of the SSTable.
*/
public SSTableScanner getScanner(DataRange dataRange)
{
return new SSTableScanner(this, dataRange, null);
}
/**
* I/O SSTableScanner
* @return A Scanner for seeking over the rows of the SSTable.
*/
public SSTableScanner getScanner()
{
return getScanner((RateLimiter) null);
}
public SSTableScanner getScanner(RateLimiter limiter)
{
return new SSTableScanner(this, DataRange.allData(partitioner), limiter);
}
/**
* Direct I/O SSTableScanner over a defined range of tokens.
*
* @param range the range of keys to cover
* @return A Scanner for seeking over the rows of the SSTable.
*/
public ICompactionScanner getScanner(Range<Token> range, RateLimiter limiter)
{
if (range == null)
return getScanner(limiter);
return getScanner(Collections.singletonList(range), limiter);
}
/**
* Direct I/O SSTableScanner over a defined collection of ranges of tokens.
*
* @param ranges the range of keys to cover
* @return A Scanner for seeking over the rows of the SSTable.
*/
public ICompactionScanner getScanner(Collection<Range<Token>> ranges, RateLimiter limiter)
{
// We want to avoid allocating a SSTableScanner if the range don't overlap the sstable (#5249)
List<Pair<Long, Long>> positions = getPositionsForRanges(Range.normalize(ranges));
if (positions.isEmpty())
return new EmptyCompactionScanner(getFilename());
else
return new SSTableScanner(this, ranges, limiter);
}
public FileDataInput getFileDataInput(long position)
{
return dfile.getSegment(position);
}
/**
* Tests if the sstable contains data newer than the given age param (in localhost currentMilli time).
* This works in conjunction with maxDataAge which is an upper bound on the create of data in this sstable.
* @param age The age to compare the maxDataAre of this sstable. Measured in millisec since epoc on this host
* @return True iff this sstable contains data that's newer than the given age parameter.
*/
public boolean newSince(long age)
{
return maxDataAge > age;
}
public void createLinks(String snapshotDirectoryPath)
{
for (Component component : components)
{
File sourceFile = new File(descriptor.filenameFor(component));
File targetLink = new File(snapshotDirectoryPath, sourceFile.getName());
FileUtils.createHardLink(sourceFile, targetLink);
}
}
/**
* TODO: Move someplace reusable
*/
public abstract static class Operator
{
public static final Operator EQ = new Equals();
public static final Operator GE = new GreaterThanOrEqualTo();
public static final Operator GT = new GreaterThan();
/**
* @param comparison The result of a call to compare/compareTo, with the desired field on the rhs.
* @return less than 0 if the operator cannot match forward, 0 if it matches, greater than 0 if it might match forward.
*/
public abstract int apply(int comparison);
final static class Equals extends Operator
{
public int apply(int comparison) { return -comparison; }
}
final static class GreaterThanOrEqualTo extends Operator
{
public int apply(int comparison) { return comparison >= 0 ? 0 : -comparison; }
}
final static class GreaterThan extends Operator
{
public int apply(int comparison) { return comparison > 0 ? 0 : 1; }
}
}
public long getBloomFilterFalsePositiveCount()
{
return bloomFilterTracker.getFalsePositiveCount();
}
public long getRecentBloomFilterFalsePositiveCount()
{
return bloomFilterTracker.getRecentFalsePositiveCount();
}
public long getBloomFilterTruePositiveCount()
{
return bloomFilterTracker.getTruePositiveCount();
}
public long getRecentBloomFilterTruePositiveCount()
{
return bloomFilterTracker.getRecentTruePositiveCount();
}
public InstrumentingCache<KeyCacheKey, RowIndexEntry> getKeyCache()
{
return keyCache;
}
public EstimatedHistogram getEstimatedRowSize()
{
return sstableMetadata.estimatedRowSize;
}
public EstimatedHistogram getEstimatedColumnCount()
{
return sstableMetadata.estimatedColumnCount;
}
public double getEstimatedDroppableTombstoneRatio(int gcBefore)
{
return sstableMetadata.getEstimatedDroppableTombstoneRatio(gcBefore);
}
public double getDroppableTombstonesBefore(int gcBefore)
{
return sstableMetadata.getDroppableTombstonesBefore(gcBefore);
}
public double getCompressionRatio()
{
return sstableMetadata.compressionRatio;
}
public ReplayPosition getReplayPosition()
{
return sstableMetadata.replayPosition;
}
public long getMinTimestamp()
{
return sstableMetadata.minTimestamp;
}
public long getMaxTimestamp()
{
return sstableMetadata.maxTimestamp;
}
public Set<Integer> getAncestors()
{
try
{
CompactionMetadata compactionMetadata = (CompactionMetadata) descriptor.getMetadataSerializer().deserialize(descriptor, MetadataType.COMPACTION);
return compactionMetadata.ancestors;
}
catch (IOException e)
{
SSTableReader.logOpenException(descriptor, e);
return Collections.emptySet();
}
}
public int getSSTableLevel()
{
return sstableMetadata.sstableLevel;
}
/**
* Reloads the sstable metadata from disk.
*
* Called after level is changed on sstable, for example if the sstable is dropped to L0
*
* Might be possible to remove in future versions
*
* @throws IOException
*/
public void reloadSSTableMetadata() throws IOException
{
this.sstableMetadata = (StatsMetadata) descriptor.getMetadataSerializer().deserialize(descriptor, MetadataType.STATS);
}
public StatsMetadata getSSTableMetadata()
{
return sstableMetadata;
}
public RandomAccessReader openDataReader(RateLimiter limiter)
{
assert limiter != null;
return compression
? CompressedThrottledReader.open(getFilename(), getCompressionMetadata(), limiter)
: ThrottledReader.open(new File(getFilename()), limiter);
}
public RandomAccessReader openDataReader()
{
return compression
? CompressedRandomAccessReader.open(getFilename(), getCompressionMetadata())
: RandomAccessReader.open(new File(getFilename()));
}
public RandomAccessReader openIndexReader()
{
return RandomAccessReader.open(new File(getIndexFilename()));
}
/**
* @param component component to get timestamp.
* @return last modified time for given component. 0 if given component does not exist or IO error occurs.
*/
public long getCreationTimeFor(Component component)
{
return new File(descriptor.filenameFor(component)).lastModified();
}
/**
* @return Number of key cache hit
*/
public long getKeyCacheHit()
{
return keyCacheHit.get();
}
/**
* @return Number of key cache request
*/
public long getKeyCacheRequest()
{
return keyCacheRequest.get();
}
/**
* @param sstables
* @return true if all desired references were acquired. Otherwise, it will unreference any partial acquisition, and return false.
*/
public static boolean acquireReferences(Iterable<SSTableReader> sstables)
{
SSTableReader failed = null;
for (SSTableReader sstable : sstables)
{
if (!sstable.acquireReference())
{
failed = sstable;
break;
}
}
if (failed == null)
return true;
for (SSTableReader sstable : sstables)
{
if (sstable == failed)
break;
sstable.releaseReference();
}
return false;
}
public static void releaseReferences(Iterable<SSTableReader> sstables)
{
for (SSTableReader sstable : sstables)
{
sstable.releaseReference();
}
}
private void dropPageCache()
{
dropPageCache(dfile.path);
dropPageCache(ifile.path);
}
private void dropPageCache(String filePath)
{
RandomAccessFile file = null;
try
{
file = new RandomAccessFile(filePath, "r");
int fd = CLibrary.getfd(file.getFD());
if (fd > 0)
{
if (logger.isDebugEnabled())
logger.debug(String.format("Dropping page cache of file %s.", filePath));
CLibrary.trySkipCache(fd, 0, 0);
}
}
catch (IOException e)
{
// we don't care if cache cleanup fails
}
finally
{
FileUtils.closeQuietly(file);
}
}
/**
* Increment the total row read count and read rate for this SSTable. This should not be incremented for range
* slice queries, row cache hits, or non-query reads, like compaction.
*/
public void incrementReadCount()
{
if (readMeter != null)
readMeter.mark();
}
protected class EmptyCompactionScanner implements ICompactionScanner
{
private final String filename;
public EmptyCompactionScanner(String filename)
{
this.filename = filename;
}
public long getLengthInBytes()
{
return 0;
}
public long getCurrentPosition()
{
return 0;
}
public String getBackingFiles()
{
return filename;
}
public boolean hasNext()
{
return false;
}
public OnDiskAtomIterator next()
{
return null;
}
public void close() throws IOException { }
public void remove() { }
}
public static class SizeComparator implements Comparator<SSTableReader>
{
public int compare(SSTableReader o1, SSTableReader o2)
{
return Longs.compare(o1.onDiskLength(), o2.onDiskLength());
}
}
}