| /** |
| * |
| * 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.hadoop.hbase.regionserver; |
| |
| import java.io.IOException; |
| import java.util.Collection; |
| import java.util.Optional; |
| import java.util.OptionalInt; |
| import java.util.OptionalLong; |
| |
| import org.apache.hadoop.hbase.Cell; |
| import org.apache.hadoop.hbase.CellComparator; |
| import org.apache.hadoop.hbase.CellUtil; |
| import org.apache.yetus.audience.InterfaceAudience; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * Utility functions for region server storage layer. |
| */ |
| @InterfaceAudience.Private |
| public class StoreUtils { |
| |
| private static final Logger LOG = LoggerFactory.getLogger(StoreUtils.class); |
| |
| /** |
| * Creates a deterministic hash code for store file collection. |
| */ |
| public static OptionalInt getDeterministicRandomSeed(Collection<HStoreFile> files) { |
| return files.stream().mapToInt(f -> f.getPath().getName().hashCode()).findFirst(); |
| } |
| |
| /** |
| * Determines whether any files in the collection are references. |
| * @param files The files. |
| */ |
| public static boolean hasReferences(Collection<HStoreFile> files) { |
| // TODO: make sure that we won't pass null here in the future. |
| return files != null && files.stream().anyMatch(HStoreFile::isReference); |
| } |
| |
| /** |
| * Gets lowest timestamp from candidate StoreFiles |
| */ |
| public static long getLowestTimestamp(Collection<HStoreFile> candidates) throws IOException { |
| long minTs = Long.MAX_VALUE; |
| for (HStoreFile storeFile : candidates) { |
| minTs = Math.min(minTs, storeFile.getModificationTimestamp()); |
| } |
| return minTs; |
| } |
| |
| /** |
| * Gets the largest file (with reader) out of the list of files. |
| * @param candidates The files to choose from. |
| * @return The largest file; null if no file has a reader. |
| */ |
| static Optional<HStoreFile> getLargestFile(Collection<HStoreFile> candidates) { |
| return candidates.stream().filter(f -> f.getReader() != null) |
| .max((f1, f2) -> Long.compare(f1.getReader().length(), f2.getReader().length())); |
| } |
| |
| /** |
| * Return the largest memstoreTS found across all storefiles in the given list. Store files that |
| * were created by a mapreduce bulk load are ignored, as they do not correspond to any specific |
| * put operation, and thus do not have a memstoreTS associated with them. |
| */ |
| public static OptionalLong getMaxMemStoreTSInList(Collection<HStoreFile> sfs) { |
| return sfs.stream().filter(sf -> !sf.isBulkLoadResult()).mapToLong(HStoreFile::getMaxMemStoreTS) |
| .max(); |
| } |
| |
| /** |
| * Return the highest sequence ID found across all storefiles in the given list. |
| */ |
| public static OptionalLong getMaxSequenceIdInList(Collection<HStoreFile> sfs) { |
| return sfs.stream().mapToLong(HStoreFile::getMaxSequenceId).max(); |
| } |
| |
| /** |
| * Gets the approximate mid-point of the given file that is optimal for use in splitting it. |
| * @param file the store file |
| * @param comparator Comparator used to compare KVs. |
| * @return The split point row, or null if splitting is not possible, or reader is null. |
| */ |
| static Optional<byte[]> getFileSplitPoint(HStoreFile file, CellComparator comparator) |
| throws IOException { |
| StoreFileReader reader = file.getReader(); |
| if (reader == null) { |
| LOG.warn("Storefile " + file + " Reader is null; cannot get split point"); |
| return Optional.empty(); |
| } |
| // Get first, last, and mid keys. Midkey is the key that starts block |
| // in middle of hfile. Has column and timestamp. Need to return just |
| // the row we want to split on as midkey. |
| Optional<Cell> optionalMidKey = reader.midKey(); |
| if (!optionalMidKey.isPresent()) { |
| return Optional.empty(); |
| } |
| Cell midKey = optionalMidKey.get(); |
| Cell firstKey = reader.getFirstKey().get(); |
| Cell lastKey = reader.getLastKey().get(); |
| // if the midkey is the same as the first or last keys, we cannot (ever) split this region. |
| if (comparator.compareRows(midKey, firstKey) == 0 || |
| comparator.compareRows(midKey, lastKey) == 0) { |
| if (LOG.isDebugEnabled()) { |
| LOG.debug("cannot split {} because midkey is the same as first or last row", file); |
| } |
| return Optional.empty(); |
| } |
| return Optional.of(CellUtil.cloneRow(midKey)); |
| } |
| |
| /** |
| * Gets the mid point of the largest file passed in as split point. |
| */ |
| static Optional<byte[]> getSplitPoint(Collection<HStoreFile> storefiles, |
| CellComparator comparator) throws IOException { |
| Optional<HStoreFile> largestFile = StoreUtils.getLargestFile(storefiles); |
| return largestFile.isPresent() ? StoreUtils.getFileSplitPoint(largestFile.get(), comparator) |
| : Optional.empty(); |
| } |
| } |