mirror of https://github.com/apache/lucene.git
LUCENE-8374 part 2/4: Reduce reads for sparse DocValues
Index jump-table for DENSE indexedDISI blocks.
This commit is contained in:
Toke Eskildsen
parent
58a7a8ada5
commit
7ad027627a
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@ -33,7 +33,7 @@ import static org.apache.lucene.codecs.lucene70.IndexedDISI.MAX_ARRAY_LENGTH;
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/**
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* Caching of IndexedDISI with two strategies:
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*
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* A lookup table for block blockCache and index.
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* A lookup table for block blockCache and index, and a rank structure for DENSE block lookups.
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*
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* The lookup table is an array of {@code long}s with an entry for each block. It allows for
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* direct jumping to the block, as opposed to iteration from the current position and forward
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@ -53,8 +53,30 @@ import static org.apache.lucene.codecs.lucene70.IndexedDISI.MAX_ARRAY_LENGTH;
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* In the case of non-existing blocks, the entry in the lookup table has index equal to the
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* previous entry and offset equal to the next non-empty block.
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*
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* The performance overhead for creating a cache instance is equivalent to visiting every 65536th
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* doc value for the given field, i.e. it scales lineary to field size.
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*
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* The rank structure for DENSE blocks is an array of unsigned {@code short}s with an entry
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* for each sub-block of 512 bits out of the 65536 bits in the outer block.
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*
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* Each rank-entry states the number of set bits within the block up to the bit before the
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* bit positioned at the start of the sub-block.
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* Note that that the rank entry of the first sub-block is always 0 and that the last entry can
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* at most be 65536-512 = 65024 and thus will always fit into an unsigned short.
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*
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* See https://en.wikipedia.org/wiki/Succinct_data_structure for details on rank structures.
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* The alternative to using the rank structure is iteration and summing of set bits for all
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* entries in the DENSE sub-block up until the wanted bit, with a worst-case of 1024 entries.
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* The rank cache overhead for a single DENSE block is 128 shorts (128*16 = 2048 bits) or
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* 1/32th.
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*
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* The ranks for the DENSE blocks are stored in a structure shared for the whole array of
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* blocks, DENSE or not. To avoid overhead that structure is itself sparse. See
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* {@link LongCompressor} for details on DENSE structure sparseness.
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*
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*
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* The performance overhead for creating a cache instance is equivalent to accessing all
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* DocValues values for the given field, i.e. it scales lineary to field size. On modern
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* hardware it is in the ballpark of 1ms for 5M values on modern hardware. Caveat lector:
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* At the point of writing, performance points are only available for 2 real-world setups.
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*/
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public class IndexedDISICache implements Accountable {
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private static final int BLOCK = 65536; // The number of docIDs that a single block represents
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@ -63,6 +85,12 @@ public class IndexedDISICache implements Accountable {
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private static final long BLOCK_INDEX_MASK = ~0L << BLOCK_INDEX_SHIFT; // The index bits in a lookup entry
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private static final long BLOCK_LOOKUP_MASK = ~BLOCK_INDEX_MASK; // The offset bits in a lookup entry
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private static final int RANK_BLOCK = 512; // The number of docIDs/bits in each rank-sub-block within a DENSE block
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static final int RANK_BLOCK_LONGS = 512/Long.SIZE; // The number of longs making up a rank-block (8)
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private static final int RANK_BLOCK_BITS = 9;
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private static final int RANKS_PER_BLOCK = BLOCK/RANK_BLOCK;
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private PackedInts.Reader rank; // One every 512 docs, sparsely represented as not all blocks are DENSE
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private long[] blockCache = null; // One every 65536 docs, contains index & slice position
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private String creationStats = "";
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private final String name; // Identifier for debug, log & inspection
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@ -86,6 +114,7 @@ public class IndexedDISICache implements Accountable {
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private IndexedDISICache() {
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this.blockCache = null;
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this.rank = null;
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this.name = "";
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}
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@ -117,10 +146,45 @@ public class IndexedDISICache implements Accountable {
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-1 : (int)(blockCache[targetBlock] >>> BLOCK_INDEX_SHIFT);
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}
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/**
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* Given a target (docID), this method returns the first docID in the entry containing the target.
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* @param target the docID for which an index is wanted.
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* @return the docID where the rank is known. This will be lte target.
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*/
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// TODO: This method requires a lot of knowledge of the intrinsics of the cache. Usage should be simplified
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int denseRankPosition(int target) {
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return target >> RANK_BLOCK_BITS << RANK_BLOCK_BITS;
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}
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public boolean hasOffsets() {
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return blockCache != null;
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}
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boolean hasRank() {
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return rank != null;
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}
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/**
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* Get the rank (index) for all set bits up to just before the given rankPosition in the block.
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* The caller is responsible for deriving the count of bits up to the docID target from the rankPosition.
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* The caller is also responsible for keeping track of set bits up to the current block.
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* Important: This only accepts rankPositions that aligns to {@link #RANK_BLOCK} boundaries.
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* Note 1: Use {@link #denseRankPosition(int)} to obtain a calid rankPosition for a wanted docID.
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* Note 2: The caller should seek to the rankPosition in the underlying slice to keep everything in sync.
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* @param rankPosition a docID target that aligns to {@link #RANK_BLOCK}.
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* @return the rank (index / set bits count) up to just before the given rankPosition.
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* If rank is disabled, -1 is returned.
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*/
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// TODO: This method requires a lot of knowledge of the intrinsics of the cache. Usage should be simplified
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int getRankInBlock(int rankPosition) {
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if (rank == null) {
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return -1;
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}
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assert rankPosition == denseRankPosition(rankPosition);
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int rankIndex = rankPosition >> RANK_BLOCK_BITS;
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return rankIndex >= rank.size() ? -1 : (int) rank.get(rankIndex);
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}
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private void updateCaches(IndexInput slice) throws IOException {
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final long startOffset = slice.getFilePointer();
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@ -135,17 +199,19 @@ public class IndexedDISICache implements Accountable {
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slice.seek(startOffset); // Leave it as we found it
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creationStats = String.format(Locale.ENGLISH,
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"name=%s, blocks=%d (ALL=%d, DENSE=%d, SPARSE=%d, EMPTY=%d), time=%dms, block=%d bytes",
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"name=%s, blocks=%d (ALL=%d, DENSE=%d, SPARSE=%d, EMPTY=%d), time=%dms, block=%d bytes, rank=%d bytes",
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name,
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largestBlock+1, statBlockALL.get(), statBlockDENSE.get(), statBlockSPARSE.get(),
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(largestBlock+1-statBlockALL.get()-statBlockDENSE.get()-statBlockSPARSE.get()),
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(System.nanoTime()-startTime)/1000000,
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blockCache == null ? 0 : blockCache.length*Long.BYTES);
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blockCache == null ? 0 : blockCache.length*Long.BYTES,
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rank == null ? 0 : rank.ramBytesUsed());
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}
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private int fillCache(
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IndexInput slice, AtomicInteger statBlockALL, AtomicInteger statBlockDENSE, AtomicInteger statBlockSPARSE)
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throws IOException {
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char[] buildRank = new char[256];
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int largestBlock = -1;
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long index = 0;
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int rankIndex = -1;
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@ -180,7 +246,27 @@ public class IndexedDISICache implements Accountable {
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// The block is DENSE
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statBlockDENSE.incrementAndGet();
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long nextBlockOffset = slice.getFilePointer() + (1 << 13);
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slice.seek(nextBlockOffset);
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int setBits = 0;
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int rankOrigo = blockIndex << 16 >> 9; // Double shift for clarity: The compiler will simplify it
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for (int rankDelta = 0 ; rankDelta < RANKS_PER_BLOCK ; rankDelta++) { // 128 rank-entries in a block
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rankIndex = rankOrigo + rankDelta;
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buildRank = ArrayUtil.grow(buildRank, rankIndex+1);
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buildRank[rankIndex] = (char)setBits;
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for (int i = 0 ; i < 512/64 ; i++) { // 8 longs for each rank-entry
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setBits += Long.bitCount(slice.readLong());
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}
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}
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assert slice.getFilePointer() == nextBlockOffset;
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}
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// Compress the buildRank as it is potentially very sparse
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if (rankIndex < 0) {
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rank = null;
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} else {
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PackedInts.Mutable ranks = PackedInts.getMutable(rankIndex, 16, PackedInts.DEFAULT); // Char = 16 bit
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for (int i = 0 ; i < rankIndex ; i++) {
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ranks.set(i, buildRank[i]);
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}
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rank = LongCompressor.compress(ranks);
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}
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return largestBlock;
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@ -189,6 +275,7 @@ public class IndexedDISICache implements Accountable {
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private void freezeCaches(int largestBlock) {
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if (largestBlock == -1) { // No set bit: Disable the caches
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blockCache = null;
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rank = null;
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return;
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}
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@ -228,7 +315,8 @@ public class IndexedDISICache implements Accountable {
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@Override
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public long ramBytesUsed() {
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return (blockCache == null ? 0 : RamUsageEstimator.sizeOf(blockCache)) +
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(rank == null ? 0 : rank.ramBytesUsed()) +
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RamUsageEstimator.NUM_BYTES_OBJECT_REF*3 +
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RamUsageEstimator.NUM_BYTES_OBJECT_HEADER + creationStats.length()*2;
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}
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}
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}
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@ -118,6 +118,8 @@ public class IndexedDISICacheFactory implements Accountable {
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IndexedDISICache cache = disiPool.get(key);
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if (cache == null) {
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// TODO: Avoid overlapping builds of the same cache
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// Both BLOCK & DENSE caches are created as they might be requested later for the field,
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// regardless of whether they are requested now
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cache = new IndexedDISICache(slice, name);
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disiPool.put(key, cache);
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}
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@ -128,6 +130,9 @@ public class IndexedDISICacheFactory implements Accountable {
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public long getDISIBlocksWithOffsetsCount() {
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return disiPool.values().stream().filter(IndexedDISICache::hasOffsets).count();
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}
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public long getDISIBlocksWithRankCount() {
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return disiPool.values().stream().filter(IndexedDISICache::hasRank).count();
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}
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@Override
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public long ramBytesUsed() {
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@ -0,0 +1,246 @@
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/*
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* Licensed to the Apache Software Foundation (ASF) under one or more
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* contributor license agreements. See the NOTICE file distributed with
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* this work for additional information regarding copyright ownership.
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* The ASF licenses this file to You under the Apache License, Version 2.0
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* (the "License"); you may not use this file except in compliance with
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* the License. You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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package org.apache.lucene.codecs.lucene70;
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import org.apache.lucene.util.MathUtil;
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import org.apache.lucene.util.RankBitSet;
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import org.apache.lucene.util.packed.PackedInts;
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/**
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* Utility class for generating compressed read-only in-memory representations of longs.
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* The representation is optimized towards random access primarily and space secondarily.
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*
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* The representation always applies delta-to-minvalue and greatest-common-divisor compression.
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*
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* Depending on the number of 0-entries and the length of the array, a sparse representation is
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* used, using rank to improve access speed. Sparseness introduces an O(1) access time overhead.
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* Sparseness can be turned off.
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*/
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public class LongCompressor {
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/**
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* The minimum amount of total values in the data set for sparse to be active.
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*/
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private static final int DEFAULT_MIN_TOTAL_VALUES_FOR_SPARSE = 10_000;
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/**
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* The minimum total amount of zero values in the data set for sparse to be active.
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*/
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private static final int DEFAULT_MIN_ZERO_VALUES_FOR_SPARSE = 500;
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/**
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* The minimum fraction of the data set that must be zero for sparse to be active.
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*/
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private static final double DEFAULT_MIN_ZERO_VALUES_FRACTION_FOR_SPARSE = 0.2; // 20% (just guessing of a value here)
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/**
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* Create a compact version of the given values.
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* @param values PackedInts with no special constraints.
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* @return a compact version of the given values or the given values if compression did not improve on heap overhead.
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*/
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public static PackedInts.Reader compress(PackedInts.Reader values) {
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return compress(values, values.size());
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}
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/**
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* Create a compact version of the given values from index 0 to length-1.
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* @param values PackedInts with no special constraints.
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* @param length the number of values to compress.
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* @return a compact version of the given values or the given values if compression did not improve on heap overhead.
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*/
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public static PackedInts.Reader compress(PackedInts.Reader values, int length) {
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return compress(values, values.size(), true);
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}
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/**
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* Create a compact version of the given values from index 0 to length-1.
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* @param values PackedInts with no special constraints.
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* @param length the number of values to compress.
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* @param allowSparse if true and is the default limits matches the input, a sparse representation will be created.
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* @return a compact version of the given values or the given values if compression did not improve on heap overhead.
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*/
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public static PackedInts.Reader compress(PackedInts.Reader values, int length, boolean allowSparse) {
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return compress(values, length, allowSparse,
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DEFAULT_MIN_TOTAL_VALUES_FOR_SPARSE,
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DEFAULT_MIN_ZERO_VALUES_FOR_SPARSE,
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DEFAULT_MIN_ZERO_VALUES_FRACTION_FOR_SPARSE);
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}
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/**
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* Create a compact version of the given values from index 0 to length-1.
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* @param values PackedInts with no special constraints.
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* @param length the number of values to compress.
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* @param allowSparse if true and is the default limits matches the input, a sparse representation will be created.
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* @param minTotalSparse the minimum absolute number of 0-entries needed for a sparse representation.
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* 0-entries are counted after minValue compression: {@code 3, 5, 3, 7, 16} has two 0-entries.
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* @return a compact version of the given values or the given values if compression did not improve on heap overhead.
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*/
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public static PackedInts.Reader compress(
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PackedInts.Reader values, int length, boolean allowSparse,
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int minTotalSparse, int minZeroSparse, double minZeroFractionSparse) {
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if (length == 0) {
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return PackedInts.getMutable(0, 1, PackedInts.DEFAULT);
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}
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final long min = getMin(values, length);
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final long gcd = getGCD(values, length, min);
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final long maxCompressed = getMax(values, length, min, gcd);
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int zeroCount;
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if (!isPossiblySparseCandidate(length, allowSparse, minTotalSparse) ||
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!isSparseCandidate(values, length, true, minTotalSparse,
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(zeroCount = countZeroes(values, length, min, gcd)), minZeroSparse, minZeroFractionSparse)) {
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// TODO: Add abort-early if it becomes apparent that no space saving is possible
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PackedInts.Mutable inner =
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PackedInts.getMutable(length, PackedInts.bitsRequired(maxCompressed), PackedInts.DEFAULT);
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for (int i = 0 ; i < length ; i++) {
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inner.set(i, (values.get(i)-min)/gcd);
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}
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PackedInts.Reader comp = new CompressedReader(inner, min, gcd);
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// Sanity check that compression worked and if not, return the original input
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return comp.ramBytesUsed() < values.ramBytesUsed() ? comp : values;
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}
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// Sparsify
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RankBitSet rank = new RankBitSet(length);
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PackedInts.Mutable inner =
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PackedInts.getMutable(values.size()-zeroCount, PackedInts.bitsRequired(maxCompressed), PackedInts.DEFAULT);
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int valueIndex = 0;
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for (int i = 0 ; i < length ; i++) {
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long value = (values.get(i)-min)/gcd;
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if (value != 0) {
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rank.set(i);
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inner.set(valueIndex++, value);
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}
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}
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rank.buildRankCache();
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PackedInts.Reader comp = new CompressedReader(inner, min, gcd, rank);
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// Sanity check that compression worked and if not, return the original input
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return comp.ramBytesUsed() < values.ramBytesUsed() ? comp : values;
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}
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// Fast check
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private static boolean isPossiblySparseCandidate(int length, boolean allowSparse, int minTotalSparse) {
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return allowSparse && minTotalSparse <= length;
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}
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// Also fast, but requires zeroCount which is slow to calculate
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private static boolean isSparseCandidate(
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PackedInts.Reader values, int length, boolean allowSparse, int minTotalSparse,
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int zeroCount, int minZeroSparse, double minZeroFractionSparse) {
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return allowSparse && minTotalSparse <= length &&
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minZeroSparse < zeroCount && minZeroFractionSparse < 1.0 * zeroCount / length;
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}
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// Not very fast as is requires #length divisions.
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private static int countZeroes(PackedInts.Reader values, int length, long min, final long gcd) {
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int zeroCount = 0;
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for (int i = 0 ; i < length ; i++) {
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if ((values.get(i)-min)/gcd == 0) { // Hope the case where gcd==1 gets JITted. We could add a switch to be sure?
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zeroCount++;
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}
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}
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return zeroCount;
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}
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static class CompressedReader extends PackedInts.Reader {
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private final PackedInts.Reader inner;
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final long min;
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final long gcd;
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final RankBitSet rank;
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CompressedReader(PackedInts.Reader inner, long min, long gcd) {
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this(inner, min, gcd, null);
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}
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CompressedReader(PackedInts.Reader inner, long min, long gcd, RankBitSet rank) {
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this.inner = inner;
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this.min = min;
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this.gcd = gcd;
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this.rank = rank;
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}
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@Override
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public int size() {
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return rank == null ? inner.size() : rank.length();
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}
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@Override
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public long get(int docID) {
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// No rank: The value at the index
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// Rank but no set bit: min*gcd
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// Rank and set bit: (The value at the rank + min) * gcd
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return (rank == null ? inner.get(docID) : rank.get(docID) ? inner.get(rank.rank(docID)) : 0) * gcd + min;
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}
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@Override
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public long ramBytesUsed() {
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return inner.ramBytesUsed() + (rank == null ? 0 : rank.ramBytesUsed());
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}
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}
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private static long getMin(PackedInts.Reader values, int length) {
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long min = Long.MAX_VALUE;
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for (int i = 0 ; i < length ; i++) {
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if (min > values.get(i)) {
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min = values.get(i);
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}
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}
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||||
return min;
|
||||
}
|
||||
|
||||
// GCD-code takes & adjusted from Lucene70DocValuesConsumer
|
||||
private static long getGCD(final PackedInts.Reader values, final int length, final long min) {
|
||||
long gcd = -1;
|
||||
|
||||
for (int i = 0 ; i < length ; i++) {
|
||||
long value = values.get(i)-min;
|
||||
if (value == 0) {
|
||||
continue;
|
||||
}
|
||||
if (gcd == -1) {
|
||||
gcd = value;
|
||||
continue;
|
||||
}
|
||||
|
||||
if (value < Long.MIN_VALUE / 2 || value > Long.MAX_VALUE / 2) {
|
||||
// in that case v - minValue might overflow and make the GCD computation return
|
||||
// wrong results. Since these extreme values are unlikely, we just discard
|
||||
// GCD computation for them
|
||||
gcd = 1;
|
||||
} else { // minValue needs to be set first
|
||||
gcd = MathUtil.gcd(gcd, value);
|
||||
}
|
||||
|
||||
if (gcd == 1) {
|
||||
break;
|
||||
}
|
||||
}
|
||||
return gcd == -1 ? 1 : gcd;
|
||||
}
|
||||
|
||||
private static long getMax(final PackedInts.Reader values, final int length, final long min, final long gcd) {
|
||||
long rawMax = Long.MIN_VALUE;
|
||||
for (int i = 0 ; i < length ; i++) {
|
||||
long value = values.get(i);
|
||||
if (value > rawMax) {
|
||||
rawMax = value;
|
||||
}
|
||||
}
|
||||
return (rawMax-min)/gcd;
|
||||
}
|
||||
}
|
||||
|
|
@ -0,0 +1,302 @@
|
|||
/*
|
||||
* 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.lucene.util;
|
||||
|
||||
import java.io.IOException;
|
||||
import java.util.Collection;
|
||||
|
||||
import org.apache.lucene.search.DocIdSetIterator;
|
||||
|
||||
/**
|
||||
* Wrapper for OpenBitSet which creates and exposes a rank cache. The rank-cache scales to 2 billion bits.
|
||||
*
|
||||
* The rankCache has a long for every 2048 bits and thus has an overhead of 3.17% relative to the given bit set.
|
||||
* Performance is O(1):
|
||||
* 1 lookup in cache,
|
||||
* a maximum of 3 sums,
|
||||
* a maximum of 8 Long.bitCounts.
|
||||
*
|
||||
* Creation performance is equivalent to a full count of all set bits in the bit set O(n).
|
||||
*
|
||||
* Note: {@link #buildRankCache()} must be called once after the bit set has been created or changed and before
|
||||
* calling {@link #rank(long)}.
|
||||
*
|
||||
* The design is based heavily on the article
|
||||
* Space-Efficient, High-Performance Rank and Select Structures on Uncompressed Bit Sequences
|
||||
* by Dong Zhou, David G. Andersen, Michael Kaminsky, Carnegie Mellon University, Intel Labs
|
||||
* http://www.cs.cmu.edu/~dga/papers/zhou-sea2013.pdf
|
||||
*/
|
||||
// Note: If the total number of set bits is <= 65535, a faster rank cache would be a short for every 512 bits
|
||||
// This is not available in the current implementation.
|
||||
// Extending the rank beyond 2 billion bits could be done by dividing the bitmap into blocks of 2b bits and
|
||||
// introducing yet another table with a rank-origo for each 2b-block
|
||||
public class RankBitSet extends BitSet {
|
||||
public static final int LOWER_BITS = 32; // Must be capable of addressing full Java array
|
||||
public static final long LOWER_MASK = ~(~1L << (LOWER_BITS-1));
|
||||
public static final int LOWER_OVER_BITS = 11;
|
||||
public static final long LOWER_OVER_MASK = ~(~1L << (LOWER_OVER_BITS-1));
|
||||
public static final int LOWER_OVER_SIZE = 2048; // Overflow bits handled by a lower block
|
||||
|
||||
public static final int BASIC_BITS = 10; // Needs to hold counts from 0-512 (513-1023 are never used)
|
||||
public static final long BASIC_MASK = ~(~1L << (BASIC_BITS-1));
|
||||
public static final int BASIC_OVER_BITS = 9;
|
||||
public static final long BASIC_OVER_MASK = ~(~1L << (BASIC_OVER_BITS-1));
|
||||
public static final int BASIC_OVER_SIZE = 512; // Overflow bits handled by a basic block
|
||||
public static final int BASIC_WORDS = BASIC_OVER_SIZE /Long.SIZE; // word == long
|
||||
/**
|
||||
* Each entry is made up of 1 long<br/>
|
||||
* Bits 63-32: 32 bit first-level absolute index.<br/>
|
||||
* Bits 30+31 are unused. These could be used to signal all-set or all-unset for the block to spare a few cycles?
|
||||
* Bits 29-0: 3 * 10 bit (0-1023) second-level relative index. Only numbers 0-512 are used.
|
||||
*/
|
||||
private long[] rankCache = null;
|
||||
private final FixedBitSet inner;
|
||||
private final int wlen; // Number of words (longs with FixedBitSet) in inner
|
||||
|
||||
public RankBitSet(int numBits) {
|
||||
this(new FixedBitSet(numBits));
|
||||
}
|
||||
|
||||
public RankBitSet(FixedBitSet inner) {
|
||||
this.inner = inner;
|
||||
wlen = inner.getBits().length;
|
||||
}
|
||||
|
||||
/**
|
||||
* Must be called after bits has changed and before {@link #rank} is called.
|
||||
*/
|
||||
public void buildRankCache() {
|
||||
rankCache = new long[(length() >>> LOWER_OVER_BITS)+1];
|
||||
long total = 0;
|
||||
int lower = 0 ;
|
||||
while (lower * LOWER_OVER_SIZE < length()) { // Full lower block processing
|
||||
final int origoWordIndex = (lower * LOWER_OVER_SIZE) >>> 6;
|
||||
// TODO: Some conditionals could be spared by checking once if all basic blocks are within size
|
||||
final long basic1 = origoWordIndex + BASIC_WORDS <= wlen ?
|
||||
BitUtil.pop_array(inner.getBits(), origoWordIndex, BASIC_WORDS) : 0;
|
||||
final long basic2 = origoWordIndex + BASIC_WORDS*2 <= wlen ?
|
||||
BitUtil.pop_array(inner.getBits(), origoWordIndex + BASIC_WORDS, BASIC_WORDS) : 0;
|
||||
final long basic3 = origoWordIndex + BASIC_WORDS*3 <= wlen ?
|
||||
BitUtil.pop_array(inner.getBits(), origoWordIndex + BASIC_WORDS *2, BASIC_WORDS) : 0;
|
||||
final long basic4 = origoWordIndex + BASIC_WORDS*4 <= wlen ?
|
||||
BitUtil.pop_array(inner.getBits(), origoWordIndex + BASIC_WORDS *3, BASIC_WORDS) : 0;
|
||||
rankCache[lower] = total << (Long.SIZE-LOWER_BITS) |
|
||||
basic1 << (BASIC_BITS *2) |
|
||||
basic2 << BASIC_BITS |
|
||||
basic3;
|
||||
total += basic1 + basic2 + basic3 + basic4;
|
||||
lower++;
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Get the rank (number of set bits up to right before the index) for the given index in O(1).
|
||||
* @param index offset in the originating bit set.
|
||||
* @return the rank for the index.
|
||||
*/
|
||||
public int rank(long index) {
|
||||
final long cache = rankCache[((int) (index >>> LOWER_OVER_BITS))];
|
||||
// lower cache (absolute)
|
||||
long rank = cache >>> (Long.SIZE-LOWER_BITS);
|
||||
int startBitIndex = (int) (index & ~LOWER_OVER_MASK);
|
||||
// basic blocks (relative)
|
||||
if (startBitIndex < index-BASIC_OVER_SIZE) {
|
||||
rank += (cache >>> (BASIC_BITS*2)) & BASIC_MASK;
|
||||
startBitIndex += BASIC_OVER_SIZE;
|
||||
if (startBitIndex < index-BASIC_OVER_SIZE) {
|
||||
rank += (cache >>> BASIC_BITS) & BASIC_MASK;
|
||||
startBitIndex += BASIC_OVER_SIZE;
|
||||
if (startBitIndex < index-BASIC_OVER_SIZE) {
|
||||
rank += cache & BASIC_MASK;
|
||||
startBitIndex += BASIC_OVER_SIZE;
|
||||
}
|
||||
}
|
||||
}
|
||||
// long.bitcount (relative)
|
||||
while(startBitIndex < index-Long.SIZE) {
|
||||
rank += Long.bitCount(inner.getBits()[startBitIndex >>> 6]);
|
||||
startBitIndex += Long.SIZE;
|
||||
}
|
||||
// Single bits (relative)
|
||||
if (startBitIndex < index) {
|
||||
/* System.out.println(String.format(Locale.ENGLISH,
|
||||
"startBitIndex=%d, index=%d, getBits()[startBitIndex>>>6=%d]=%s, index-startBitIndex=%d, mask=%s",
|
||||
startBitIndex, index, startBitIndex>>>6, Long.toBinaryString(getBits()[startBitIndex>>>6]),
|
||||
index-startBitIndex, Long.toBinaryString(~(~1L << (index-startBitIndex-1)))));*/
|
||||
rank += Long.bitCount(inner.getBits()[startBitIndex >>> 6] & ~(~1L << (index-startBitIndex-1)));
|
||||
}
|
||||
// for (int i = startBitIndex ; i < index ; i++) {
|
||||
// rank += fastGet(i) ? 1 : 0;
|
||||
// }
|
||||
return (int) rank;
|
||||
}
|
||||
|
||||
@Override
|
||||
public long ramBytesUsed() {
|
||||
return RamUsageEstimator.alignObjectSize(RamUsageEstimator.NUM_BYTES_OBJECT_REF*2 +
|
||||
Integer.BYTES + Long.BYTES) +
|
||||
inner.ramBytesUsed() +
|
||||
(rankCache == null ? 0 :
|
||||
RamUsageEstimator.NUM_BYTES_ARRAY_HEADER + Long.BYTES*rankCache.length);
|
||||
}
|
||||
|
||||
/* Delegations to inner bit set below */
|
||||
|
||||
public static FixedBitSet ensureCapacity(FixedBitSet bits, int numBits) {
|
||||
return FixedBitSet.ensureCapacity(bits, numBits);
|
||||
}
|
||||
|
||||
public static int bits2words(int numBits) {
|
||||
return FixedBitSet.bits2words(numBits);
|
||||
}
|
||||
|
||||
public static long intersectionCount(FixedBitSet a, FixedBitSet b) {
|
||||
return FixedBitSet.intersectionCount(a, b);
|
||||
}
|
||||
|
||||
public static long unionCount(FixedBitSet a, FixedBitSet b) {
|
||||
return FixedBitSet.unionCount(a, b);
|
||||
}
|
||||
|
||||
public static long andNotCount(FixedBitSet a, FixedBitSet b) {
|
||||
return FixedBitSet.andNotCount(a, b);
|
||||
}
|
||||
|
||||
@Override
|
||||
public int length() {
|
||||
return inner.length();
|
||||
}
|
||||
|
||||
public long[] getBits() {
|
||||
return inner.getBits();
|
||||
}
|
||||
|
||||
@Override
|
||||
public int cardinality() {
|
||||
return inner.cardinality();
|
||||
}
|
||||
|
||||
@Override
|
||||
public boolean get(int index) {
|
||||
return inner.get(index);
|
||||
}
|
||||
|
||||
@Override
|
||||
public void set(int index) {
|
||||
inner.set(index);
|
||||
}
|
||||
|
||||
public boolean getAndSet(int index) {
|
||||
return inner.getAndSet(index);
|
||||
}
|
||||
|
||||
@Override
|
||||
public void clear(int index) {
|
||||
inner.clear(index);
|
||||
}
|
||||
|
||||
public boolean getAndClear(int index) {
|
||||
return inner.getAndClear(index);
|
||||
}
|
||||
|
||||
@Override
|
||||
public int nextSetBit(int index) {
|
||||
return inner.nextSetBit(index);
|
||||
}
|
||||
|
||||
@Override
|
||||
public int prevSetBit(int index) {
|
||||
return inner.prevSetBit(index);
|
||||
}
|
||||
|
||||
@Override
|
||||
public void or(DocIdSetIterator iter) throws IOException {
|
||||
inner.or(iter);
|
||||
}
|
||||
|
||||
public void or(FixedBitSet other) {
|
||||
inner.or(other);
|
||||
}
|
||||
|
||||
public void xor(FixedBitSet other) {
|
||||
inner.xor(other);
|
||||
}
|
||||
|
||||
public void xor(DocIdSetIterator iter) throws IOException {
|
||||
inner.xor(iter);
|
||||
}
|
||||
|
||||
public boolean intersects(FixedBitSet other) {
|
||||
return inner.intersects(other);
|
||||
}
|
||||
|
||||
public void and(FixedBitSet other) {
|
||||
inner.and(other);
|
||||
}
|
||||
|
||||
public void andNot(FixedBitSet other) {
|
||||
inner.andNot(other);
|
||||
}
|
||||
|
||||
public boolean scanIsEmpty() {
|
||||
return inner.scanIsEmpty();
|
||||
}
|
||||
|
||||
public void flip(int startIndex, int endIndex) {
|
||||
inner.flip(startIndex, endIndex);
|
||||
}
|
||||
|
||||
public void flip(int index) {
|
||||
inner.flip(index);
|
||||
}
|
||||
|
||||
public void set(int startIndex, int endIndex) {
|
||||
inner.set(startIndex, endIndex);
|
||||
}
|
||||
|
||||
@Override
|
||||
public void clear(int startIndex, int endIndex) {
|
||||
inner.clear(startIndex, endIndex);
|
||||
}
|
||||
|
||||
@Override
|
||||
public int hashCode() {
|
||||
return inner.hashCode();
|
||||
}
|
||||
|
||||
public static FixedBitSet copyOf(Bits bits) {
|
||||
return FixedBitSet.copyOf(bits);
|
||||
}
|
||||
|
||||
public Bits asReadOnlyBits() {
|
||||
return inner.asReadOnlyBits();
|
||||
}
|
||||
|
||||
public static BitSet of(DocIdSetIterator it, int maxDoc) throws IOException {
|
||||
return BitSet.of(it, maxDoc);
|
||||
}
|
||||
|
||||
@Override
|
||||
public int approximateCardinality() {
|
||||
return inner.approximateCardinality();
|
||||
}
|
||||
|
||||
@Override
|
||||
public Collection<Accountable> getChildResources() {
|
||||
return inner.getChildResources();
|
||||
}
|
||||
}
|
||||
|
|
@ -0,0 +1,87 @@
|
|||
/*
|
||||
* 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.lucene.codecs.lucene70;
|
||||
|
||||
import java.util.Locale;
|
||||
import java.util.Random;
|
||||
|
||||
import org.apache.lucene.util.LuceneTestCase;
|
||||
import org.apache.lucene.util.packed.PackedInts;
|
||||
|
||||
public class TestLongCompressor extends LuceneTestCase {
|
||||
|
||||
// Simple money test that builds a collection of random longs, compresses them with LongCompressor and
|
||||
// checks if all values from the compressed version are equal to the source
|
||||
public void testLongCompressorMonkey() {
|
||||
final int RUNS = 10;
|
||||
final int[] MAX_SIZES = new int[]{0, 1, 10, 1000, 100_000};
|
||||
final int[] MAX_VALUE = new int[]{0, 1, 10, 1000, 100_000};
|
||||
for (int run = 0 ; run < RUNS ; run++) {
|
||||
for (int maxSize: MAX_SIZES) {
|
||||
int size = maxSize == 0 ? 0 : random().nextInt(maxSize);
|
||||
for (int maxValue: MAX_VALUE) {
|
||||
int minValue = maxValue == 0 ? 0 : random().nextInt(maxValue);
|
||||
double minChance = random().nextDouble();
|
||||
longCompressorMonkeyTest(run, size, minValue, maxValue, minChance, random().nextLong());
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
public void testVerySparse() {
|
||||
final int SIZE = 674932;
|
||||
final int EVERY = SIZE/896;
|
||||
PackedInts.Mutable ranks = PackedInts.getMutable(674932, 16, PackedInts.DEFAULT);
|
||||
for (int i = 0 ; i < SIZE; i+=EVERY) {
|
||||
ranks.set(i, random().nextInt(65535));
|
||||
}
|
||||
PackedInts.Reader sparsed = LongCompressor.compress(ranks);
|
||||
assertFalse("The input and the sparsed should not be the same", ranks == sparsed);
|
||||
}
|
||||
|
||||
private void longCompressorMonkeyTest(
|
||||
int run, int size, int minValue, int maxValue, double minChance, long randomSeed) {
|
||||
final String description = String.format(Locale.ENGLISH,
|
||||
"run=%d, size=%d, minValue=%d, maxValue=%d, minChance=%1.2f, seed=%d",
|
||||
run, size, minValue, maxValue, minChance, randomSeed);
|
||||
Random innerRandom = new Random(randomSeed);
|
||||
PackedInts.Mutable expected = PackedInts.getMutable(size, PackedInts.bitsRequired(maxValue), PackedInts.DEFAULT);
|
||||
for (int i = 0 ; i < size ; i++) {
|
||||
if (innerRandom.nextDouble() <= minChance) {
|
||||
continue;
|
||||
}
|
||||
expected.set(i, maxValue-minValue == 0 ? minValue : innerRandom.nextInt(maxValue-minValue)+minValue);
|
||||
}
|
||||
assertSparseValid(description, expected);
|
||||
}
|
||||
|
||||
private void assertSparseValid(String description, PackedInts.Reader values) {
|
||||
try {
|
||||
PackedInts.Reader sparsed = LongCompressor.compress(values, values.size());
|
||||
|
||||
for (int i = 0; i < values.size(); i++) {
|
||||
assertEquals("The value at index " + i + " should be as expected for " + description,
|
||||
values.get(i), sparsed.get(i));
|
||||
}
|
||||
} catch (Exception e) {
|
||||
throw new RuntimeException("Unexpected Exception for " + description, e);
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
}
|
||||
|
|
@ -0,0 +1,107 @@
|
|||
/*
|
||||
* 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.lucene.util;
|
||||
|
||||
import java.util.Locale;
|
||||
import java.util.Random;
|
||||
|
||||
public class TestRankBitSet extends LuceneTestCase {
|
||||
|
||||
public void testSingleWord() {
|
||||
RankBitSet rank = new RankBitSet(60);
|
||||
rank.set(20);
|
||||
rank.buildRankCache();
|
||||
|
||||
assertEquals("The rank at index 20 should be correct", 0, rank.rank(20));
|
||||
assertEquals("The rank at index 21 should be correct", 1, rank.rank(21));
|
||||
}
|
||||
|
||||
public void testSecondWord() {
|
||||
RankBitSet rank = new RankBitSet(100);
|
||||
rank.set(70);
|
||||
rank.buildRankCache();
|
||||
|
||||
assertEquals("The rank at index 70 should be correct", 0, rank.rank(70));
|
||||
assertEquals("The rank at index 71 should be correct", 1, rank.rank(71));
|
||||
}
|
||||
|
||||
public void testThirdWord() {
|
||||
RankBitSet rank = new RankBitSet(200);
|
||||
rank.set(130);
|
||||
rank.buildRankCache();
|
||||
|
||||
assertEquals("The rank at index 130 should be correct", 0, rank.rank(130));
|
||||
assertEquals("The rank at index 131 should be correct", 1, rank.rank(131));
|
||||
}
|
||||
|
||||
public void testSecondLower() {
|
||||
RankBitSet rank = new RankBitSet(3000);
|
||||
rank.set(2500);
|
||||
rank.buildRankCache();
|
||||
|
||||
assertEquals("The rank at index 2500 should be correct", 0, rank.rank(2500));
|
||||
assertEquals("The rank at index 2500 should be correct", 1, rank.rank(2501));
|
||||
}
|
||||
|
||||
public void testSpecific282() {
|
||||
RankBitSet rank = new RankBitSet(448);
|
||||
rank.set(282);
|
||||
rank.buildRankCache();
|
||||
|
||||
assertEquals("The rank at index 288 should be correct", 1, rank.rank(288));
|
||||
}
|
||||
|
||||
public void testSpecific1031() {
|
||||
RankBitSet rank = new RankBitSet(1446);
|
||||
rank.set(1031);
|
||||
rank.buildRankCache();
|
||||
|
||||
assertEquals("The rank at index 1057 should be correct", 1, rank.rank(1057));
|
||||
}
|
||||
|
||||
public void testMonkeys() {
|
||||
monkey(20, 8000, 40);
|
||||
}
|
||||
|
||||
@Slow
|
||||
public void testManyMonkeys() {
|
||||
monkey(20, 100000, 400);
|
||||
}
|
||||
|
||||
public void monkey(int runs, int sizeMax, int setMax) {
|
||||
Random random = random();
|
||||
//Random random = new Random(87);
|
||||
for (int run = 0 ; run < runs ; run++) {
|
||||
final int size = random.nextInt(sizeMax-1)+1;
|
||||
RankBitSet rank = new RankBitSet(size);
|
||||
int doSet = random.nextInt(setMax);
|
||||
for (int s = 0 ; s < doSet ; s++) {
|
||||
int index = random.nextInt(size);
|
||||
rank.set(index);
|
||||
}
|
||||
rank.buildRankCache();
|
||||
int setbits = 0;
|
||||
for (int i = 0 ; i < size ; i++) {
|
||||
assertEquals(String.format(Locale.ENGLISH, "run=%d, index=%d/%d, setbits=%d", run, i, size, setbits),
|
||||
setbits, rank.rank(i));
|
||||
if (rank.get(i)) {
|
||||
setbits++;
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
Loading…
Reference in New Issue