Jaromir Hamala
GitHub
parent
77872e197d
commit
927880b97e
@ -17,5 +17,5 @@
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# -XX:+UnlockDiagnosticVMOptions -XX:PrintAssemblyOptions=intel -XX:CompileCommand=print,*.CalculateAverage_mtopolnik::recordMeasurementAndAdvanceCursor"
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# -XX:InlineSmallCode=10000 -XX:-TieredCompilation -XX:CICompilerCount=2 -XX:CompileThreshold=1000\
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java --enable-preview \
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java -XX:+UseParallelGC --enable-preview \
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--class-path target/average-1.0.0-SNAPSHOT.jar dev.morling.onebrc.CalculateAverage_jerrinot
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@ -22,15 +22,24 @@ import java.io.RandomAccessFile;
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import java.lang.foreign.Arena;
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import java.lang.reflect.Field;
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import java.nio.channels.FileChannel.MapMode;
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import java.util.Map;
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import java.util.TreeMap;
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import java.util.*;
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/**
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* I figured out it would be very hard to win the main competition of the One Billion Rows Challenge.
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* but I think this code has a good chance to win a special prize for the Ugliest Solution ever! :)
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*
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* Anyway, if you can make sense out of not exactly idiomatic Java code, and you enjoy pushing performance limits
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* then QuestDB - the fastest open-source time-series database - is hiring: https://questdb.io/careers/core-database-engineer/
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*
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*/
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public class CalculateAverage_jerrinot {
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private static final Unsafe UNSAFE = unsafe();
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private static final String MEASUREMENTS_TXT = "measurements.txt";
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// todo: with hyper-threading enable we would be better of with availableProcessors / 2;
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// todo: validate the testing env. params.
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private static final int THREAD_COUNT = Runtime.getRuntime().availableProcessors();
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// private static final int THREAD_COUNT = 4;
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private static final long SEPARATOR_PATTERN = 0x3B3B3B3B3B3B3B3BL;
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private static Unsafe unsafe() {
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@ -72,7 +81,7 @@ public class CalculateAverage_jerrinot {
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Processor[] processors = new Processor[THREAD_COUNT];
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Thread[] threads = new Thread[THREAD_COUNT];
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for (int i = 0; i < THREAD_COUNT; i++) {
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for (int i = 0; i < THREAD_COUNT - 1; i++) {
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long startA = chunkStartOffsets[i * chunkPerThread];
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long endA = chunkStartOffsets[i * chunkPerThread + 1];
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long startB = chunkStartOffsets[i * chunkPerThread + 1];
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@ -89,8 +98,22 @@ public class CalculateAverage_jerrinot {
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thread.start();
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}
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int ownIndex = THREAD_COUNT - 1;
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long startA = chunkStartOffsets[ownIndex * chunkPerThread];
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long endA = chunkStartOffsets[ownIndex * chunkPerThread + 1];
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long startB = chunkStartOffsets[ownIndex * chunkPerThread + 1];
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long endB = chunkStartOffsets[ownIndex * chunkPerThread + 2];
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long startC = chunkStartOffsets[ownIndex * chunkPerThread + 2];
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long endC = chunkStartOffsets[ownIndex * chunkPerThread + 3];
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long startD = chunkStartOffsets[ownIndex * chunkPerThread + 3];
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long endD = chunkStartOffsets[ownIndex * chunkPerThread + 4];
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Processor processor = new Processor(startA, endA, startB, endB, startC, endC, startD, endD);
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processor.run();
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var accumulator = new TreeMap<String, Processor.StationStats>();
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for (int i = 0; i < THREAD_COUNT; i++) {
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processor.accumulateStatus(accumulator);
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for (int i = 0; i < THREAD_COUNT - 1; i++) {
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Thread t = threads[i];
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t.join();
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processors[i].accumulateStatus(accumulator);
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@ -131,7 +154,7 @@ public class CalculateAverage_jerrinot {
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private static class Processor implements Runnable {
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private static final int MAP_SLOT_COUNT = ceilPow2(10000);
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private static final int STATION_MAX_NAME_BYTES = 104;
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private static final int STATION_MAX_NAME_BYTES = 120;
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private static final long COUNT_OFFSET = 0;
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private static final long MIN_OFFSET = 4;
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@ -162,23 +185,16 @@ public class CalculateAverage_jerrinot {
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private long endC;
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private long cursorD;
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private long endD;
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private long maskA;
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private long maskB;
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private long maskC;
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private long maskD;
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// private long maxClusterLen;
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// credit: merykitty
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private long parseAndStoreTemperature(long startCursor, long baseEntryPtr) {
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long word = UNSAFE.getLong(startCursor);
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final long negateda = ~word;
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final int dotPos = Long.numberOfTrailingZeros(negateda & 0x10101000);
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final long signed = (negateda << 59) >> 63;
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final long removeSignMask = ~(signed & 0xFF);
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final long digits = ((word & removeSignMask) << (28 - dotPos)) & 0x0F000F0F00L;
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final long absValue = ((digits * 0x640a0001) >>> 32) & 0x3FF;
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final int temperature = (int) ((absValue ^ signed) - signed);
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private long parseAndStoreTemperature(long startCursor, long baseEntryPtr, long word) {
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// long word = UNSAFE.getLong(startCursor);
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long countPtr = baseEntryPtr + COUNT_OFFSET;
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int cnt = UNSAFE.getInt(countPtr);
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UNSAFE.putInt(countPtr, cnt + 1);
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long minPtr = baseEntryPtr + MIN_OFFSET;
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long maxPtr = baseEntryPtr + MAX_OFFSET;
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long sumPtr = baseEntryPtr + SUM_OFFSET;
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@ -186,16 +202,23 @@ public class CalculateAverage_jerrinot {
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int min = UNSAFE.getInt(minPtr);
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int max = UNSAFE.getInt(maxPtr);
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long sum = UNSAFE.getLong(sumPtr);
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// try if min/max intrinsics are paying off
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// maybe braching is better? the branch is becoming more predictable with
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// each new sample.
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max = Math.max(max, temperature);
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min = Math.min(min, temperature);
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final long negateda = ~word;
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final int dotPos = Long.numberOfTrailingZeros(negateda & 0x10101000);
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final long signed = (negateda << 59) >> 63;
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final long removeSignMask = ~(signed & 0xFF);
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final long digits = ((word & removeSignMask) << (28 - dotPos)) & 0x0F000F0F00L;
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final long absValue = ((digits * 0x640a0001) >>> 32) & 0x3FF;
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final int temperature = (int) ((absValue ^ signed) - signed);
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sum += temperature;
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UNSAFE.putInt(countPtr, UNSAFE.getInt(countPtr) + 1);
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UNSAFE.putInt(minPtr, min);
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UNSAFE.putInt(maxPtr, max);
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UNSAFE.putLong(sumPtr, sum);
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if (temperature > max) {
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UNSAFE.putInt(maxPtr, temperature);
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}
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if (temperature < min) {
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UNSAFE.putInt(minPtr, temperature);
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}
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return startCursor + (dotPos / 8) + 3;
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}
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@ -227,13 +250,13 @@ public class CalculateAverage_jerrinot {
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int count = UNSAFE.getInt(baseAddress + COUNT_OFFSET);
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long sum = UNSAFE.getLong(baseAddress + SUM_OFFSET);
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// todo: lambdas bootstrap probably cost us
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accumulator.compute(name, (_, v) -> {
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var v = accumulator.get(name);
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if (v == null) {
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return new StationStats(min, max, count, sum);
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accumulator.put(name, new StationStats(min, max, count, sum));
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}
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else {
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accumulator.put(name, new StationStats(Math.min(v.min, min), Math.max(v.max, max), v.count + count, v.sum + sum));
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}
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return new StationStats(Math.min(v.min, min), Math.max(v.max, max), v.count + count, v.sum + sum);
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});
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}
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}
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@ -260,11 +283,22 @@ public class CalculateAverage_jerrinot {
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private void doTail() {
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// todo: we would be probably better of without all that code dup. ("compilers hates him!")
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// System.out.println("done ILP");
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doOne(cursorA, endA);
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// System.out.println("done A");
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doOne(cursorB, endB);
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// System.out.println("done B");
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doOne(cursorC, endC);
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// System.out.println("done C");
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doOne(cursorD, endD);
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// System.out.println("done D");
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}
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private void doOne(long cursorA, long endA) {
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while (cursorA < endA) {
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long startA = cursorA;
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long delimiterWordA = UNSAFE.getLong(cursorA);
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long hashA = 0;
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maskA = getDelimiterMask(delimiterWordA);
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long maskA = getDelimiterMask(delimiterWordA);
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while (maskA == 0) {
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hashA ^= delimiterWordA;
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cursorA += 8;
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@ -273,81 +307,15 @@ public class CalculateAverage_jerrinot {
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}
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final int delimiterByteA = Long.numberOfTrailingZeros(maskA);
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final long semicolonA = cursorA + (delimiterByteA >> 3);
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final long maskedWordA = delimiterWordA & ((maskA >>> 7) - 1);
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final long maskedWordA = delimiterWordA & ((maskA - 1) ^ maskA) >>> 8;
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hashA ^= maskedWordA;
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int intHashA = (int) (hashA ^ (hashA >> 32));
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intHashA = intHashA ^ (intHashA >> 17);
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long baseEntryPtrA = getOrCreateEntryBaseOffset(semicolonA, startA, intHashA, maskedWordA);
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cursorA = parseAndStoreTemperature(semicolonA + 1, baseEntryPtrA);
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long temperatureWordA = UNSAFE.getLong(semicolonA + 1);
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cursorA = parseAndStoreTemperature(semicolonA + 1, baseEntryPtrA, temperatureWordA);
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}
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// System.out.println("done A");
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while (cursorB < endB) {
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long startB = cursorB;
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long delimiterWordB = UNSAFE.getLong(cursorB);
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long hashB = 0;
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maskB = getDelimiterMask(delimiterWordB);
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while (maskB == 0) {
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hashB ^= delimiterWordB;
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cursorB += 8;
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delimiterWordB = UNSAFE.getLong(cursorB);
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maskB = getDelimiterMask(delimiterWordB);
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}
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final int delimiterByteB = Long.numberOfTrailingZeros(maskB);
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final long semicolonB = cursorB + (delimiterByteB >> 3);
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final long maskedWordB = delimiterWordB & ((maskB >>> 7) - 1);
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hashB ^= maskedWordB;
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int intHashB = (int) (hashB ^ (hashB >> 32));
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intHashB = intHashB ^ (intHashB >> 17);
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long baseEntryPtrB = getOrCreateEntryBaseOffset(semicolonB, startB, intHashB, maskedWordB);
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cursorB = parseAndStoreTemperature(semicolonB + 1, baseEntryPtrB);
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}
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// System.out.println("done B");
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while (cursorC < endC) {
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long startC = cursorC;
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long delimiterWordC = UNSAFE.getLong(cursorC);
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long hashC = 0;
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maskC = getDelimiterMask(delimiterWordC);
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while (maskC == 0) {
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hashC ^= delimiterWordC;
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cursorC += 8;
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delimiterWordC = UNSAFE.getLong(cursorC);
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maskC = getDelimiterMask(delimiterWordC);
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}
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final int delimiterByteC = Long.numberOfTrailingZeros(maskC);
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final long semicolonC = cursorC + (delimiterByteC >> 3);
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final long maskedWordC = delimiterWordC & ((maskC >>> 7) - 1);
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hashC ^= maskedWordC;
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int intHashC = (int) (hashC ^ (hashC >> 32));
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intHashC = intHashC ^ (intHashC >> 17);
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long baseEntryPtrC = getOrCreateEntryBaseOffset(semicolonC, startC, intHashC, maskedWordC);
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cursorC = parseAndStoreTemperature(semicolonC + 1, baseEntryPtrC);
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}
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// System.out.println("done C");
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while (cursorD < endD) {
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long startD = cursorD;
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long delimiterWordD = UNSAFE.getLong(cursorD);
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long hashD = 0;
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maskD = getDelimiterMask(delimiterWordD);
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while (maskD == 0) {
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hashD ^= delimiterWordD;
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cursorD += 8;
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delimiterWordD = UNSAFE.getLong(cursorD);
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maskD = getDelimiterMask(delimiterWordD);
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}
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final int delimiterByteD = Long.numberOfTrailingZeros(maskD);
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final long semicolonD = cursorD + (delimiterByteD >> 3);
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final long maskedWordD = delimiterWordD & ((maskD >>> 7) - 1);
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hashD ^= maskedWordD;
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int intHashD = (int) (hashD ^ (hashD >> 32));
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intHashD = intHashD ^ (intHashD >> 17);
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long baseEntryPtrD = getOrCreateEntryBaseOffset(semicolonD, startD, intHashD, maskedWordD);
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cursorD = parseAndStoreTemperature(semicolonD + 1, baseEntryPtrD);
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}
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// System.out.println("done D");
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}
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@Override
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@ -359,10 +327,14 @@ public class CalculateAverage_jerrinot {
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long startC = cursorC;
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long startD = cursorD;
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long delimiterWordA = UNSAFE.getLong(cursorA);
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long delimiterWordB = UNSAFE.getLong(cursorB);
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long delimiterWordC = UNSAFE.getLong(cursorC);
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long delimiterWordD = UNSAFE.getLong(cursorD);
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long currentWordA = UNSAFE.getLong(startA);
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// long delimiterWordA2 = UNSAFE.getLong(startA + 8);
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long currentWordB = UNSAFE.getLong(startB);
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// long delimiterWordB2 = UNSAFE.getLong(startB + 8);
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long currentWordC = UNSAFE.getLong(startC);
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// long delimiterWordCa = UNSAFE.getLong(startC + 8);
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long currentWordD = UNSAFE.getLong(startD);
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// long delimiterWordD2 = UNSAFE.getLong(startD + 8);
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long hashA = 0;
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long hashB = 0;
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@ -370,58 +342,62 @@ public class CalculateAverage_jerrinot {
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long hashD = 0;
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// credits for the hashing idea: royvanrijn
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maskA = getDelimiterMask(delimiterWordA);
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long maskA = getDelimiterMask(currentWordA);
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while (maskA == 0) {
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hashA ^= delimiterWordA;
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hashA ^= currentWordA;
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cursorA += 8;
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delimiterWordA = UNSAFE.getLong(cursorA);
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maskA = getDelimiterMask(delimiterWordA);
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currentWordA = UNSAFE.getLong(cursorA);
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maskA = getDelimiterMask(currentWordA);
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}
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final int delimiterByteA = Long.numberOfTrailingZeros(maskA);
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final long semicolonA = cursorA + (delimiterByteA >> 3);
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final long maskedWordA = delimiterWordA & ((maskA >>> 7) - 1);
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long temperatureWordA = UNSAFE.getLong(semicolonA + 1);
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final long maskedWordA = currentWordA & ((maskA - 1) ^ maskA) >>> 8;
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hashA ^= maskedWordA;
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int intHashA = (int) (hashA ^ (hashA >> 32));
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intHashA = intHashA ^ (intHashA >> 17);
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maskB = getDelimiterMask(delimiterWordB);
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long maskB = getDelimiterMask(currentWordB);
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while (maskB == 0) {
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hashB ^= delimiterWordB;
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hashB ^= currentWordB;
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cursorB += 8;
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delimiterWordB = UNSAFE.getLong(cursorB);
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maskB = getDelimiterMask(delimiterWordB);
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currentWordB = UNSAFE.getLong(cursorB);
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maskB = getDelimiterMask(currentWordB);
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}
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final int delimiterByteB = Long.numberOfTrailingZeros(maskB);
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final long semicolonB = cursorB + (delimiterByteB >> 3);
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final long maskedWordB = delimiterWordB & ((maskB >>> 7) - 1);
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long temperatureWordB = UNSAFE.getLong(semicolonB + 1);
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final long maskedWordB = currentWordB & ((maskB - 1) ^ maskB) >>> 8;
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hashB ^= maskedWordB;
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int intHashB = (int) (hashB ^ (hashB >> 32));
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intHashB = intHashB ^ (intHashB >> 17);
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maskC = getDelimiterMask(delimiterWordC);
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long maskC = getDelimiterMask(currentWordC);
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while (maskC == 0) {
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hashC ^= delimiterWordC;
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hashC ^= currentWordC;
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cursorC += 8;
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delimiterWordC = UNSAFE.getLong(cursorC);
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maskC = getDelimiterMask(delimiterWordC);
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currentWordC = UNSAFE.getLong(cursorC);
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maskC = getDelimiterMask(currentWordC);
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}
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final int delimiterByteC = Long.numberOfTrailingZeros(maskC);
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final long semicolonC = cursorC + (delimiterByteC >> 3);
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final long maskedWordC = delimiterWordC & ((maskC >>> 7) - 1);
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long temperatureWordC = UNSAFE.getLong(semicolonC + 1);
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final long maskedWordC = currentWordC & ((maskC - 1) ^ maskC) >>> 8;
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hashC ^= maskedWordC;
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int intHashC = (int) (hashC ^ (hashC >> 32));
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intHashC = intHashC ^ (intHashC >> 17);
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maskD = getDelimiterMask(delimiterWordD);
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long maskD = getDelimiterMask(currentWordD);
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while (maskD == 0) {
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hashD ^= delimiterWordD;
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hashD ^= currentWordD;
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cursorD += 8;
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delimiterWordD = UNSAFE.getLong(cursorD);
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maskD = getDelimiterMask(delimiterWordD);
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currentWordD = UNSAFE.getLong(cursorD);
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maskD = getDelimiterMask(currentWordD);
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}
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final int delimiterByteD = Long.numberOfTrailingZeros(maskD);
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final long semicolonD = cursorD + (delimiterByteD >> 3);
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final long maskedWordD = delimiterWordD & ((maskD >>> 7) - 1);
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long temperatureWordD = UNSAFE.getLong(semicolonD + 1);
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final long maskedWordD = currentWordD & ((maskD - 1) ^ maskD) >>> 8;
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hashD ^= maskedWordD;
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int intHashD = (int) (hashD ^ (hashD >> 32));
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intHashD = intHashD ^ (intHashD >> 17);
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@ -431,51 +407,74 @@ public class CalculateAverage_jerrinot {
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long baseEntryPtrC = getOrCreateEntryBaseOffset(semicolonC, startC, intHashC, maskedWordC);
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long baseEntryPtrD = getOrCreateEntryBaseOffset(semicolonD, startD, intHashD, maskedWordD);
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cursorA = parseAndStoreTemperature(semicolonA + 1, baseEntryPtrA);
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cursorB = parseAndStoreTemperature(semicolonB + 1, baseEntryPtrB);
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cursorC = parseAndStoreTemperature(semicolonC + 1, baseEntryPtrC);
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cursorD = parseAndStoreTemperature(semicolonD + 1, baseEntryPtrD);
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cursorA = parseAndStoreTemperature(semicolonA + 1, baseEntryPtrA, temperatureWordA);
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cursorB = parseAndStoreTemperature(semicolonB + 1, baseEntryPtrB, temperatureWordB);
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cursorC = parseAndStoreTemperature(semicolonC + 1, baseEntryPtrC, temperatureWordC);
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cursorD = parseAndStoreTemperature(semicolonD + 1, baseEntryPtrD, temperatureWordD);
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}
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doTail();
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}
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|
||||
private long getOrCreateEntryBaseOffset(long semicolonA, long startA, int intHashA, long maskedWordA) {
|
||||
int lenA = (int) (semicolonA - startA);
|
||||
// hashSet.add(intHashA);
|
||||
long lenLong = semicolonA - startA;
|
||||
int lenA = (int) lenLong;
|
||||
|
||||
// assert lenA != 0;
|
||||
// byte[] nameArr = new byte[lenA];
|
||||
// for (int i = 0; i < lenA; i++) {
|
||||
// nameArr[i] = UNSAFE.getByte(startA + i);
|
||||
// }
|
||||
// String nameStr = new String(nameArr);
|
||||
// Integer oldHash = nameToHash.put(nameStr, intHashA);
|
||||
// assert oldHash == null || oldHash == intHashA : "name: " + nameStr + ", old hash = " + oldHash + ", new hash = " + intHashA;
|
||||
|
||||
long mapIndexA = intHashA & MAP_MASK;
|
||||
// long clusterLen = 0;
|
||||
for (;;) {
|
||||
long basePtr = mapIndexA * MAP_ENTRY_SIZE_BYTES + map;
|
||||
long lenPtr = basePtr + LEN_OFFSET;
|
||||
int len = UNSAFE.getInt(lenPtr);
|
||||
if (len == 0) {
|
||||
if (len == lenA) {
|
||||
if (nameMatch(startA, maskedWordA, basePtr, lenLong)) {
|
||||
// if (clusterLen > maxClusterLen) {
|
||||
// maxClusterLen = clusterLen;
|
||||
// System.out.println("max cluster len: " + clusterLen);
|
||||
// }
|
||||
return basePtr;
|
||||
}
|
||||
}
|
||||
else if (len == 0) {
|
||||
// todo: uncommon branch maybe?
|
||||
// empty slot
|
||||
UNSAFE.copyMemory(semicolonA - lenA, basePtr + NAME_OFFSET, lenA);
|
||||
UNSAFE.putInt(lenPtr, lenA);
|
||||
// todo: this could be a single putLong()
|
||||
UNSAFE.putInt(basePtr + MAX_OFFSET, Integer.MIN_VALUE);
|
||||
UNSAFE.putInt(basePtr + MIN_OFFSET, Integer.MAX_VALUE);
|
||||
return basePtr;
|
||||
}
|
||||
if (len == lenA) {
|
||||
boolean match = true;
|
||||
mapIndexA = ++mapIndexA & MAP_MASK;
|
||||
// clusterLen++;
|
||||
}
|
||||
}
|
||||
|
||||
private static boolean nameMatch(long startA, long maskedWordA, long basePtr, long len) {
|
||||
long namePtr = basePtr + NAME_OFFSET;
|
||||
int fullLen = (len >> 3) << 3;
|
||||
long fullLen = len & ~7L;
|
||||
long offset;
|
||||
|
||||
// todo: this is worth exploring further.
|
||||
// @mtopolnik has an interesting algo with 2 unconditioned long loads: this is sufficient
|
||||
// for majority of names. so we would be left with just a single branch which is almost never taken?
|
||||
for (offset = 0; offset < fullLen; offset += 8) {
|
||||
match &= (UNSAFE.getLong(startA + offset) == UNSAFE.getLong(namePtr + offset));
|
||||
if (UNSAFE.getLong(startA + offset) != UNSAFE.getLong(namePtr + offset)) {
|
||||
return false;
|
||||
}
|
||||
}
|
||||
|
||||
long maskedWordInMap = UNSAFE.getLong(namePtr + offset);
|
||||
match &= (maskedWordInMap == maskedWordA);
|
||||
|
||||
if (match) {
|
||||
return basePtr;
|
||||
}
|
||||
}
|
||||
mapIndexA = ++mapIndexA & MAP_MASK;
|
||||
}
|
||||
long maskedWordInMap = UNSAFE.getLong(namePtr + fullLen);
|
||||
return (maskedWordInMap == maskedWordA);
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
Loading…
Reference in New Issue
Block a user