/**
*
* 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
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*/
package org.apache.hadoop.hbase.regionserver.compactions;
import static org.apache.hadoop.hbase.regionserver.StripeStoreFileManager.OPEN_KEY;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hbase.CellComparator;
import org.apache.hadoop.hbase.classification.InterfaceAudience;
import org.apache.hadoop.hbase.regionserver.StoreConfigInformation;
import org.apache.hadoop.hbase.regionserver.StoreFile;
import org.apache.hadoop.hbase.regionserver.StoreUtils;
import org.apache.hadoop.hbase.regionserver.StripeStoreConfig;
import org.apache.hadoop.hbase.regionserver.StripeStoreFlusher;
import org.apache.hadoop.hbase.regionserver.throttle.ThroughputController;
import org.apache.hadoop.hbase.security.User;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.hbase.util.ConcatenatedLists;
import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
import org.apache.hadoop.hbase.util.Pair;
import com.google.common.collect.ImmutableList;
/**
* Stripe store implementation of compaction policy.
*/
@InterfaceAudience.Private
public class StripeCompactionPolicy extends CompactionPolicy {
private final static Log LOG = LogFactory.getLog(StripeCompactionPolicy.class);
// Policy used to compact individual stripes.
private ExploringCompactionPolicy stripePolicy = null;
private StripeStoreConfig config;
public StripeCompactionPolicy(
Configuration conf, StoreConfigInformation storeConfigInfo, StripeStoreConfig config) {
super(conf, storeConfigInfo);
this.config = config;
stripePolicy = new ExploringCompactionPolicy(conf, storeConfigInfo);
}
public List<StoreFile> preSelectFilesForCoprocessor(StripeInformationProvider si,
List<StoreFile> filesCompacting) {
// We sincerely hope nobody is messing with us with their coprocessors.
// If they do, they are very likely to shoot themselves in the foot.
// We'll just exclude all the filesCompacting from the list.
ArrayList<StoreFile> candidateFiles = new ArrayList<>(si.getStorefiles());
candidateFiles.removeAll(filesCompacting);
return candidateFiles;
}
public StripeCompactionRequest createEmptyRequest(
StripeInformationProvider si, CompactionRequest request) {
// Treat as L0-ish compaction with fixed set of files, and hope for the best.
if (si.getStripeCount() > 0) {
return new BoundaryStripeCompactionRequest(request, si.getStripeBoundaries());
}
Pair<Long, Integer> targetKvsAndCount = estimateTargetKvs(
request.getFiles(), this.config.getInitialCount());
return new SplitStripeCompactionRequest(
request, OPEN_KEY, OPEN_KEY, targetKvsAndCount.getSecond(), targetKvsAndCount.getFirst());
}
public StripeStoreFlusher.StripeFlushRequest selectFlush(CellComparator comparator,
StripeInformationProvider si, int kvCount) {
if (this.config.isUsingL0Flush()) {
// L0 is used, return dumb request.
return new StripeStoreFlusher.StripeFlushRequest(comparator);
}
if (si.getStripeCount() == 0) {
// No stripes - start with the requisite count, derive KVs per stripe.
int initialCount = this.config.getInitialCount();
return new StripeStoreFlusher.SizeStripeFlushRequest(comparator, initialCount,
kvCount / initialCount);
}
// There are stripes - do according to the boundaries.
return new StripeStoreFlusher.BoundaryStripeFlushRequest(comparator, si.getStripeBoundaries());
}
public StripeCompactionRequest selectCompaction(StripeInformationProvider si,
List<StoreFile> filesCompacting, boolean isOffpeak) throws IOException {
// TODO: first cut - no parallel compactions. To have more fine grained control we
// probably need structure more sophisticated than a list.
if (!filesCompacting.isEmpty()) {
LOG.debug("Not selecting compaction: " + filesCompacting.size() + " files compacting");
return null;
}
// We are going to do variations of compaction in strict order of preference.
// A better/more advanced approach is to use a heuristic to see which one is "more
// necessary" at current time.
// This can happen due to region split. We can skip it later; for now preserve
// compact-all-things behavior.
Collection<StoreFile> allFiles = si.getStorefiles();
if (StoreUtils.hasReferences(allFiles)) {
LOG.debug("There are references in the store; compacting all files");
long targetKvs = estimateTargetKvs(allFiles, config.getInitialCount()).getFirst();
SplitStripeCompactionRequest request = new SplitStripeCompactionRequest(
allFiles, OPEN_KEY, OPEN_KEY, targetKvs);
request.setMajorRangeFull();
return request;
}
int stripeCount = si.getStripeCount();
List<StoreFile> l0Files = si.getLevel0Files();
// See if we need to make new stripes.
boolean shouldCompactL0 = (this.config.getLevel0MinFiles() <= l0Files.size());
if (stripeCount == 0) {
if (!shouldCompactL0) return null; // nothing to do.
return selectNewStripesCompaction(si);
}
boolean canDropDeletesNoL0 = l0Files.isEmpty();
if (shouldCompactL0) {
if (!canDropDeletesNoL0) {
// If we need to compact L0, see if we can add something to it, and drop deletes.
StripeCompactionRequest result = selectSingleStripeCompaction(
si, true, canDropDeletesNoL0, isOffpeak);
if (result != null) return result;
}
LOG.debug("Selecting L0 compaction with " + l0Files.size() + " files");
return new BoundaryStripeCompactionRequest(l0Files, si.getStripeBoundaries());
}
// Try to delete fully expired stripes
StripeCompactionRequest result = selectExpiredMergeCompaction(si, canDropDeletesNoL0);
if (result != null) return result;
// Ok, nothing special here, let's see if we need to do a common compaction.
// This will also split the stripes that are too big if needed.
return selectSingleStripeCompaction(si, false, canDropDeletesNoL0, isOffpeak);
}
public boolean needsCompactions(StripeInformationProvider si, List<StoreFile> filesCompacting) {
// Approximation on whether we need compaction.
return filesCompacting.isEmpty()
&& (StoreUtils.hasReferences(si.getStorefiles())
|| (si.getLevel0Files().size() >= this.config.getLevel0MinFiles())
|| needsSingleStripeCompaction(si));
}
@Override
public boolean shouldPerformMajorCompaction(Collection<StoreFile> filesToCompact)
throws IOException {
return false; // there's never a major compaction!
}
@Override
public boolean throttleCompaction(long compactionSize) {
return compactionSize > comConf.getThrottlePoint();
}
/**
* @param si StoreFileManager.
* @return Whether any stripe potentially needs compaction.
*/
protected boolean needsSingleStripeCompaction(StripeInformationProvider si) {
int minFiles = this.config.getStripeCompactMinFiles();
for (List<StoreFile> stripe : si.getStripes()) {
if (stripe.size() >= minFiles) return true;
}
return false;
}
protected StripeCompactionRequest selectSingleStripeCompaction(StripeInformationProvider si,
boolean includeL0, boolean canDropDeletesWithoutL0, boolean isOffpeak) throws IOException {
ArrayList<ImmutableList<StoreFile>> stripes = si.getStripes();
int bqIndex = -1;
List<StoreFile> bqSelection = null;
int stripeCount = stripes.size();
long bqTotalSize = -1;
for (int i = 0; i < stripeCount; ++i) {
// If we want to compact L0 to drop deletes, we only want whole-stripe compactions.
// So, pass includeL0 as 2nd parameter to indicate that.
List<StoreFile> selection = selectSimpleCompaction(stripes.get(i),
!canDropDeletesWithoutL0 && includeL0, isOffpeak);
if (selection.isEmpty()) continue;
long size = 0;
for (StoreFile sf : selection) {
size += sf.getReader().length();
}
if (bqSelection == null || selection.size() > bqSelection.size() ||
(selection.size() == bqSelection.size() && size < bqTotalSize)) {
bqSelection = selection;
bqIndex = i;
bqTotalSize = size;
}
}
if (bqSelection == null) {
LOG.debug("No good compaction is possible in any stripe");
return null;
}
List<StoreFile> filesToCompact = new ArrayList<>(bqSelection);
// See if we can, and need to, split this stripe.
int targetCount = 1;
long targetKvs = Long.MAX_VALUE;
boolean hasAllFiles = filesToCompact.size() == stripes.get(bqIndex).size();
String splitString = "";
if (hasAllFiles && bqTotalSize >= config.getSplitSize()) {
if (includeL0) {
// We want to avoid the scenario where we compact a stripe w/L0 and then split it.
// So, if we might split, don't compact the stripe with L0.
return null;
}
Pair<Long, Integer> kvsAndCount = estimateTargetKvs(filesToCompact, config.getSplitCount());
targetKvs = kvsAndCount.getFirst();
targetCount = kvsAndCount.getSecond();
splitString = "; the stripe will be split into at most "
+ targetCount + " stripes with " + targetKvs + " target KVs";
}
LOG.debug("Found compaction in a stripe with end key ["
+ Bytes.toString(si.getEndRow(bqIndex)) + "], with "
+ filesToCompact.size() + " files of total size " + bqTotalSize + splitString);
// See if we can drop deletes.
StripeCompactionRequest req;
if (includeL0) {
assert hasAllFiles;
List<StoreFile> l0Files = si.getLevel0Files();
LOG.debug("Adding " + l0Files.size() + " files to compaction to be able to drop deletes");
ConcatenatedLists<StoreFile> sfs = new ConcatenatedLists<>();
sfs.addSublist(filesToCompact);
sfs.addSublist(l0Files);
req = new BoundaryStripeCompactionRequest(sfs, si.getStripeBoundaries());
} else {
req = new SplitStripeCompactionRequest(
filesToCompact, si.getStartRow(bqIndex), si.getEndRow(bqIndex), targetCount, targetKvs);
}
if (hasAllFiles && (canDropDeletesWithoutL0 || includeL0)) {
req.setMajorRange(si.getStartRow(bqIndex), si.getEndRow(bqIndex));
}
req.getRequest().setOffPeak(isOffpeak);
return req;
}
/**
* Selects the compaction of a single stripe using default policy.
* @param sfs Files.
* @param allFilesOnly Whether a compaction of all-or-none files is needed.
* @return The resulting selection.
*/
private List<StoreFile> selectSimpleCompaction(
List<StoreFile> sfs, boolean allFilesOnly, boolean isOffpeak) {
int minFilesLocal = Math.max(
allFilesOnly ? sfs.size() : 0, this.config.getStripeCompactMinFiles());
int maxFilesLocal = Math.max(this.config.getStripeCompactMaxFiles(), minFilesLocal);
return stripePolicy.applyCompactionPolicy(sfs, false, isOffpeak, minFilesLocal, maxFilesLocal);
}
/**
* Selects the compaction that compacts all files (to be removed later).
* @param si StoreFileManager.
* @param targetStripeCount Target stripe count.
* @param targetSize Target stripe size.
* @return The compaction.
*/
private StripeCompactionRequest selectCompactionOfAllFiles(StripeInformationProvider si,
int targetStripeCount, long targetSize) {
Collection<StoreFile> allFiles = si.getStorefiles();
SplitStripeCompactionRequest request = new SplitStripeCompactionRequest(
allFiles, OPEN_KEY, OPEN_KEY, targetStripeCount, targetSize);
request.setMajorRangeFull();
LOG.debug("Selecting a compaction that includes all " + allFiles.size() + " files");
return request;
}
private StripeCompactionRequest selectNewStripesCompaction(StripeInformationProvider si) {
List<StoreFile> l0Files = si.getLevel0Files();
Pair<Long, Integer> kvsAndCount = estimateTargetKvs(l0Files, config.getInitialCount());
LOG.debug("Creating " + kvsAndCount.getSecond() + " initial stripes with "
+ kvsAndCount.getFirst() + " kvs each via L0 compaction of " + l0Files.size() + " files");
SplitStripeCompactionRequest request = new SplitStripeCompactionRequest(
si.getLevel0Files(), OPEN_KEY, OPEN_KEY, kvsAndCount.getSecond(), kvsAndCount.getFirst());
request.setMajorRangeFull(); // L0 only, can drop deletes.
return request;
}
private StripeCompactionRequest selectExpiredMergeCompaction(
StripeInformationProvider si, boolean canDropDeletesNoL0) {
long cfTtl = this.storeConfigInfo.getStoreFileTtl();
if (cfTtl == Long.MAX_VALUE) {
return null; // minversion might be set, cannot delete old files
}
long timestampCutoff = EnvironmentEdgeManager.currentTime() - cfTtl;
// Merge the longest sequence of stripes where all files have expired, if any.
int start = -1, bestStart = -1, length = 0, bestLength = 0;
ArrayList<ImmutableList<StoreFile>> stripes = si.getStripes();
OUTER: for (int i = 0; i < stripes.size(); ++i) {
for (StoreFile storeFile : stripes.get(i)) {
if (storeFile.getReader().getMaxTimestamp() < timestampCutoff) continue;
// Found non-expired file, this stripe has to stay.
if (length > bestLength) {
bestStart = start;
bestLength = length;
}
start = -1;
length = 0;
continue OUTER;
}
if (start == -1) {
start = i;
}
++length;
}
if (length > bestLength) {
bestStart = start;
bestLength = length;
}
if (bestLength == 0) return null;
if (bestLength == 1) {
// This is currently inefficient. If only one stripe expired, we will rewrite some
// entire stripe just to delete some expired files because we rely on metadata and it
// cannot simply be updated in an old file. When we either determine stripe dynamically
// or move metadata to manifest, we can just drop the "expired stripes".
if (bestStart == (stripes.size() - 1)) return null;
++bestLength;
}
LOG.debug("Merging " + bestLength + " stripes to delete expired store files");
int endIndex = bestStart + bestLength - 1;
ConcatenatedLists<StoreFile> sfs = new ConcatenatedLists<>();
sfs.addAllSublists(stripes.subList(bestStart, endIndex + 1));
SplitStripeCompactionRequest result = new SplitStripeCompactionRequest(sfs,
si.getStartRow(bestStart), si.getEndRow(endIndex), 1, Long.MAX_VALUE);
if (canDropDeletesNoL0) {
result.setMajorRangeFull();
}
return result;
}
private static long getTotalKvCount(final Collection<StoreFile> candidates) {
long totalSize = 0;
for (StoreFile storeFile : candidates) {
totalSize += storeFile.getReader().getEntries();
}
return totalSize;
}
public static long getTotalFileSize(final Collection<StoreFile> candidates) {
long totalSize = 0;
for (StoreFile storeFile : candidates) {
totalSize += storeFile.getReader().length();
}
return totalSize;
}
private Pair<Long, Integer> estimateTargetKvs(Collection<StoreFile> files, double splitCount) {
// If the size is larger than what we target, we don't want to split into proportionally
// larger parts and then have to split again very soon. So, we will increase the multiplier
// by one until we get small enough parts. E.g. 5Gb stripe that should have been split into
// 2 parts when it was 3Gb will be split into 3x1.67Gb parts, rather than 2x2.5Gb parts.
long totalSize = getTotalFileSize(files);
long targetPartSize = config.getSplitPartSize();
assert targetPartSize > 0 && splitCount > 0;
double ratio = totalSize / (splitCount * targetPartSize); // ratio of real to desired size
while (ratio > 1.0) {
// Ratio of real to desired size if we increase the multiplier.
double newRatio = totalSize / ((splitCount + 1.0) * targetPartSize);
if ((1.0 / newRatio) >= ratio) break; // New ratio is < 1.0, but further than the last one.
ratio = newRatio;
splitCount += 1.0;
}
long kvCount = (long)(getTotalKvCount(files) / splitCount);
return new Pair<>(kvCount, (int)Math.ceil(splitCount));
}
/** Stripe compaction request wrapper. */
public abstract static class StripeCompactionRequest {
protected CompactionRequest request;
protected byte[] majorRangeFromRow = null, majorRangeToRow = null;
public List<Path> execute(StripeCompactor compactor,
ThroughputController throughputController) throws IOException {
return execute(compactor, throughputController, null);
}
/**
* Executes the request against compactor (essentially, just calls correct overload of
* compact method), to simulate more dynamic dispatch.
* @param compactor Compactor.
* @return result of compact(...)
*/
public abstract List<Path> execute(StripeCompactor compactor,
ThroughputController throughputController, User user) throws IOException;
public StripeCompactionRequest(CompactionRequest request) {
this.request = request;
}
/**
* Sets compaction "major range". Major range is the key range for which all
* the files are included, so they can be treated like major-compacted files.
* @param startRow Left boundary, inclusive.
* @param endRow Right boundary, exclusive.
*/
public void setMajorRange(byte[] startRow, byte[] endRow) {
this.majorRangeFromRow = startRow;
this.majorRangeToRow = endRow;
}
public CompactionRequest getRequest() {
return this.request;
}
public void setRequest(CompactionRequest request) {
assert request != null;
this.request = request;
this.majorRangeFromRow = this.majorRangeToRow = null;
}
}
/**
* Request for stripe compactor that will cause it to split the source files into several
* separate files at the provided boundaries.
*/
private static class BoundaryStripeCompactionRequest extends StripeCompactionRequest {
private final List<byte[]> targetBoundaries;
/**
* @param request Original request.
* @param targetBoundaries New files should be written with these boundaries.
*/
public BoundaryStripeCompactionRequest(CompactionRequest request,
List<byte[]> targetBoundaries) {
super(request);
this.targetBoundaries = targetBoundaries;
}
public BoundaryStripeCompactionRequest(Collection<StoreFile> files,
List<byte[]> targetBoundaries) {
this(new CompactionRequest(files), targetBoundaries);
}
@Override
public List<Path> execute(StripeCompactor compactor,
ThroughputController throughputController, User user) throws IOException {
return compactor.compact(this.request, this.targetBoundaries, this.majorRangeFromRow,
this.majorRangeToRow, throughputController, user);
}
}
/**
* Request for stripe compactor that will cause it to split the source files into several
* separate files into based on key-value count, as well as file count limit.
* Most of the files will be roughly the same size. The last file may be smaller or larger
* depending on the interplay of the amount of data and maximum number of files allowed.
*/
private static class SplitStripeCompactionRequest extends StripeCompactionRequest {
private final byte[] startRow, endRow;
private final int targetCount;
private final long targetKvs;
/**
* @param request Original request.
* @param startRow Left boundary of the range to compact, inclusive.
* @param endRow Right boundary of the range to compact, exclusive.
* @param targetCount The maximum number of stripe to compact into.
* @param targetKvs The KV count of each segment. If targetKvs*targetCount is less than
* total number of kvs, all the overflow data goes into the last stripe.
*/
public SplitStripeCompactionRequest(CompactionRequest request,
byte[] startRow, byte[] endRow, int targetCount, long targetKvs) {
super(request);
this.startRow = startRow;
this.endRow = endRow;
this.targetCount = targetCount;
this.targetKvs = targetKvs;
}
public SplitStripeCompactionRequest(
CompactionRequest request, byte[] startRow, byte[] endRow, long targetKvs) {
this(request, startRow, endRow, Integer.MAX_VALUE, targetKvs);
}
public SplitStripeCompactionRequest(
Collection<StoreFile> files, byte[] startRow, byte[] endRow, long targetKvs) {
this(files, startRow, endRow, Integer.MAX_VALUE, targetKvs);
}
public SplitStripeCompactionRequest(Collection<StoreFile> files,
byte[] startRow, byte[] endRow, int targetCount, long targetKvs) {
this(new CompactionRequest(files), startRow, endRow, targetCount, targetKvs);
}
@Override
public List<Path> execute(StripeCompactor compactor,
ThroughputController throughputController, User user) throws IOException {
return compactor.compact(this.request, this.targetCount, this.targetKvs, this.startRow,
this.endRow, this.majorRangeFromRow, this.majorRangeToRow, throughputController, user);
}
/** Set major range of the compaction to the entire compaction range.
* See {@link #setMajorRange(byte[], byte[])}. */
public void setMajorRangeFull() {
setMajorRange(this.startRow, this.endRow);
}
}
/** The information about stripes that the policy needs to do its stuff */
public static interface StripeInformationProvider {
public Collection<StoreFile> getStorefiles();
/**
* Gets the start row for a given stripe.
* @param stripeIndex Stripe index.
* @return Start row. May be an open key.
*/
public byte[] getStartRow(int stripeIndex);
/**
* Gets the end row for a given stripe.
* @param stripeIndex Stripe index.
* @return End row. May be an open key.
*/
public byte[] getEndRow(int stripeIndex);
/**
* @return Level 0 files.
*/
public List<StoreFile> getLevel0Files();
/**
* @return All stripe boundaries; including the open ones on both ends.
*/
public List<byte[]> getStripeBoundaries();
/**
* @return The stripes.
*/
public ArrayList<ImmutableList<StoreFile>> getStripes();
/**
* @return Stripe count.
*/
public int getStripeCount();
}
}