Dmitry challenge
This commit is contained in:
Dmitry Bufistov
committed by
Gunnar Morling
Gunnar Morling
parent
3c36b5b0a8
commit
0ca7c485aa
398
src/main/java/dev/morling/onebrc/CalculateAverage_bufistov.java
Normal file
398
src/main/java/dev/morling/onebrc/CalculateAverage_bufistov.java
Normal file
@@ -0,0 +1,398 @@
|
||||
/*
|
||||
* Copyright 2023 The original authors
|
||||
*
|
||||
* Licensed 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 dev.morling.onebrc;
|
||||
|
||||
import static java.lang.Math.toIntExact;
|
||||
|
||||
import java.nio.MappedByteBuffer;
|
||||
import java.nio.channels.FileChannel;
|
||||
import java.nio.charset.StandardCharsets;
|
||||
import java.util.ArrayList;
|
||||
import java.util.Arrays;
|
||||
import java.util.Comparator;
|
||||
import java.util.HashMap;
|
||||
import java.util.concurrent.Callable;
|
||||
import java.util.concurrent.ExecutorService;
|
||||
import java.util.concurrent.Executors;
|
||||
|
||||
import java.io.FileInputStream;
|
||||
import java.io.IOException;
|
||||
import java.util.concurrent.Future;
|
||||
|
||||
class ResultRow {
|
||||
byte[] station;
|
||||
|
||||
String stationString;
|
||||
long min, max, count, suma;
|
||||
|
||||
ResultRow() {
|
||||
}
|
||||
|
||||
ResultRow(byte[] station, long value) {
|
||||
this.station = new byte[station.length];
|
||||
System.arraycopy(station, 0, this.station, 0, station.length);
|
||||
this.min = value;
|
||||
this.max = value;
|
||||
this.count = 1;
|
||||
this.suma = value;
|
||||
}
|
||||
|
||||
ResultRow(long value) {
|
||||
this.min = value;
|
||||
this.max = value;
|
||||
this.count = 1;
|
||||
this.suma = value;
|
||||
}
|
||||
|
||||
void setStation(MappedByteBuffer byteBuffer, int startPosition, int endPosition) {
|
||||
this.station = new byte[endPosition - startPosition];
|
||||
byteBuffer.slice(startPosition, station.length).get(this.station, 0, station.length);
|
||||
}
|
||||
|
||||
public String toString() {
|
||||
stationString = new String(station, StandardCharsets.UTF_8);
|
||||
return stationString + "=" + round(min / 10.0) + "/" + round(suma / 10.0 / count) + "/" + round(max / 10.0);
|
||||
}
|
||||
|
||||
private double round(double value) {
|
||||
return Math.round(value * 10.0) / 10.0;
|
||||
}
|
||||
|
||||
ResultRow update(long newValue) {
|
||||
this.count += 1;
|
||||
this.suma += newValue;
|
||||
if (newValue < this.min) {
|
||||
this.min = newValue;
|
||||
}
|
||||
else if (newValue > this.max) {
|
||||
this.max = newValue;
|
||||
}
|
||||
return this;
|
||||
}
|
||||
|
||||
ResultRow merge(ResultRow another) {
|
||||
this.count += another.count;
|
||||
this.suma += another.suma;
|
||||
this.min = Math.min(this.min, another.min);
|
||||
this.max = Math.max(this.max, another.max);
|
||||
return this;
|
||||
}
|
||||
}
|
||||
|
||||
class ByteArrayWrapper {
|
||||
private final byte[] data;
|
||||
|
||||
public ByteArrayWrapper(byte[] data) {
|
||||
this.data = data;
|
||||
}
|
||||
|
||||
@Override
|
||||
public boolean equals(Object other) {
|
||||
return Arrays.equals(data, ((ByteArrayWrapper) other).data);
|
||||
}
|
||||
|
||||
@Override
|
||||
public int hashCode() {
|
||||
return Arrays.hashCode(data);
|
||||
}
|
||||
}
|
||||
|
||||
class OpenHash {
|
||||
ResultRow[] data;
|
||||
int dataSizeMask;
|
||||
|
||||
// ResultRow metrics = new ResultRow();
|
||||
|
||||
public OpenHash(int capacityPow2) {
|
||||
assert capacityPow2 <= 20;
|
||||
int dataSize = 1 << capacityPow2;
|
||||
dataSizeMask = dataSize - 1;
|
||||
data = new ResultRow[dataSize];
|
||||
}
|
||||
|
||||
int hashByteArray(byte[] array) {
|
||||
int result = 0;
|
||||
long mask = 0;
|
||||
for (int i = 0; i < array.length; ++i, mask = ((mask + 1) & 3)) {
|
||||
result += array[i] << mask;
|
||||
}
|
||||
return result & dataSizeMask;
|
||||
}
|
||||
|
||||
void merge(byte[] station, long value, int hashValue) {
|
||||
while (data[hashValue] != null && !Arrays.equals(station, data[hashValue].station)) {
|
||||
hashValue += 1;
|
||||
hashValue &= dataSizeMask;
|
||||
}
|
||||
if (data[hashValue] == null) {
|
||||
data[hashValue] = new ResultRow(station, value);
|
||||
}
|
||||
else {
|
||||
data[hashValue].update(value);
|
||||
}
|
||||
// metrics.update(delta);
|
||||
}
|
||||
|
||||
void merge(byte[] station, long value) {
|
||||
merge(station, value, hashByteArray(station));
|
||||
}
|
||||
|
||||
void merge(MappedByteBuffer byteBuffer, final int startPosition, final int endPosition, int hashValue, final long value) {
|
||||
while (data[hashValue] != null && !equalsToStation(byteBuffer, startPosition, endPosition, data[hashValue].station)) {
|
||||
hashValue += 1;
|
||||
hashValue &= dataSizeMask;
|
||||
}
|
||||
if (data[hashValue] == null) {
|
||||
data[hashValue] = new ResultRow(value);
|
||||
data[hashValue].setStation(byteBuffer, startPosition, endPosition);
|
||||
}
|
||||
else {
|
||||
data[hashValue].update(value);
|
||||
}
|
||||
}
|
||||
|
||||
boolean equalsToStation(MappedByteBuffer byteBuffer, int startPosition, int endPosition, byte[] station) {
|
||||
if (endPosition - startPosition != station.length) {
|
||||
return false;
|
||||
}
|
||||
for (int i = 0; i < station.length; ++i, ++startPosition) {
|
||||
if (byteBuffer.get(startPosition) != station[i])
|
||||
return false;
|
||||
}
|
||||
return true;
|
||||
}
|
||||
|
||||
HashMap<ByteArrayWrapper, ResultRow> toJavaHashMap() {
|
||||
HashMap<ByteArrayWrapper, ResultRow> result = new HashMap<>(20000);
|
||||
for (int i = 0; i < data.length; ++i) {
|
||||
if (data[i] != null) {
|
||||
var key = new ByteArrayWrapper(data[i].station);
|
||||
result.put(key, data[i]);
|
||||
}
|
||||
}
|
||||
return result;
|
||||
}
|
||||
}
|
||||
|
||||
public class CalculateAverage_bufistov {
|
||||
|
||||
static final long LINE_SEPARATOR = '\n';
|
||||
|
||||
public static class FileRead implements Callable<HashMap<ByteArrayWrapper, ResultRow>> {
|
||||
|
||||
private final FileChannel fileChannel;
|
||||
private long currentLocation;
|
||||
private int bytesToRead;
|
||||
|
||||
private final int hashCapacityPow2 = 18;
|
||||
private final int hashCapacityMask = (1 << hashCapacityPow2) - 1;
|
||||
|
||||
public FileRead(long startLocation, int bytesToRead, FileChannel fileChannel) {
|
||||
this.currentLocation = startLocation;
|
||||
this.bytesToRead = bytesToRead;
|
||||
this.fileChannel = fileChannel;
|
||||
}
|
||||
|
||||
@Override
|
||||
public HashMap<ByteArrayWrapper, ResultRow> call() throws IOException {
|
||||
try {
|
||||
OpenHash openHash = new OpenHash(hashCapacityPow2);
|
||||
log("Reading the channel: " + currentLocation + ":" + bytesToRead);
|
||||
byte[] suffix = new byte[128];
|
||||
if (currentLocation > 0) {
|
||||
toLineBegin(suffix);
|
||||
}
|
||||
while (bytesToRead > 0) {
|
||||
int bufferSize = Math.min(1 << 24, bytesToRead);
|
||||
MappedByteBuffer byteBuffer = fileChannel.map(FileChannel.MapMode.READ_ONLY, currentLocation, bufferSize);
|
||||
bytesToRead -= bufferSize;
|
||||
currentLocation += bufferSize;
|
||||
int suffixBytes = 0;
|
||||
if (currentLocation < fileChannel.size()) {
|
||||
suffixBytes = toLineBegin(suffix);
|
||||
}
|
||||
processChunk(byteBuffer, bufferSize, suffix, suffixBytes, openHash);
|
||||
}
|
||||
log("Done Reading the channel: " + currentLocation + ":" + bytesToRead);
|
||||
return openHash.toJavaHashMap();
|
||||
}
|
||||
catch (Exception e) {
|
||||
e.printStackTrace();
|
||||
throw e;
|
||||
}
|
||||
}
|
||||
|
||||
byte getByte(long position) throws IOException {
|
||||
MappedByteBuffer byteBuffer = fileChannel.map(FileChannel.MapMode.READ_ONLY, position, 1);
|
||||
return byteBuffer.get();
|
||||
}
|
||||
|
||||
int toLineBegin(byte[] suffix) throws IOException {
|
||||
int bytesConsumed = 0;
|
||||
if (getByte(currentLocation - 1) != LINE_SEPARATOR) {
|
||||
while (getByte(currentLocation) != LINE_SEPARATOR) { // Small bug here if last chunk is less than a line and has no '\n' at the end. Valid input should have '\n' for all rows.
|
||||
suffix[bytesConsumed++] = getByte(currentLocation);
|
||||
++currentLocation;
|
||||
--bytesToRead;
|
||||
}
|
||||
++currentLocation;
|
||||
--bytesToRead;
|
||||
}
|
||||
return bytesConsumed;
|
||||
}
|
||||
|
||||
void processChunk(MappedByteBuffer byteBuffer, int bufferSize, byte[] suffix, int suffixBytes, OpenHash result) {
|
||||
int nameBegin = 0;
|
||||
int nameEnd = -1;
|
||||
int numberBegin = -1;
|
||||
int currentHash = 0;
|
||||
int currentMask = 0;
|
||||
int nameHash = 0;
|
||||
for (int currentPosition = 0; currentPosition < bufferSize; ++currentPosition) {
|
||||
byte nextByte = byteBuffer.get(currentPosition);
|
||||
if (nextByte == ';') {
|
||||
nameEnd = currentPosition;
|
||||
numberBegin = currentPosition + 1;
|
||||
nameHash = currentHash & hashCapacityMask;
|
||||
}
|
||||
else if (nextByte == LINE_SEPARATOR) {
|
||||
long value = getValue(byteBuffer, numberBegin, currentPosition);
|
||||
// log("Station name: '" + getStationName(byteBuffer, nameBegin, nameEnd) + "' value: " + value + " hash: " + nameHash);
|
||||
result.merge(byteBuffer, nameBegin, nameEnd, nameHash, value);
|
||||
nameBegin = currentPosition + 1;
|
||||
currentHash = 0;
|
||||
currentMask = 0;
|
||||
}
|
||||
else {
|
||||
currentHash += (nextByte << currentMask);
|
||||
currentMask = (currentMask + 1) & 3;
|
||||
}
|
||||
}
|
||||
if (nameBegin < bufferSize) {
|
||||
byte[] lastLine = new byte[bufferSize - nameBegin + suffixBytes];
|
||||
byte[] prefix = new byte[bufferSize - nameBegin];
|
||||
byteBuffer.slice(nameBegin, prefix.length).get(prefix, 0, prefix.length);
|
||||
System.arraycopy(prefix, 0, lastLine, 0, prefix.length);
|
||||
System.arraycopy(suffix, 0, lastLine, prefix.length, suffixBytes);
|
||||
processLastLine(lastLine, result);
|
||||
}
|
||||
}
|
||||
|
||||
void processLastLine(byte[] lastLine, OpenHash result) {
|
||||
int numberBegin = -1;
|
||||
byte[] stationName = null;
|
||||
for (int i = 0; i < lastLine.length; ++i) {
|
||||
if (lastLine[i] == ';') {
|
||||
stationName = new byte[i];
|
||||
System.arraycopy(lastLine, 0, stationName, 0, stationName.length);
|
||||
numberBegin = i + 1;
|
||||
break;
|
||||
}
|
||||
}
|
||||
long value = getValue(lastLine, numberBegin);
|
||||
// log("Station name: '" + new String(stationName, StandardCharsets.UTF_8) + "' value: " + value);
|
||||
result.merge(stationName, value);
|
||||
}
|
||||
|
||||
long getValue(MappedByteBuffer byteBuffer, int startLocation, int endLocation) {
|
||||
byte nextByte = byteBuffer.get(startLocation);
|
||||
boolean negate = nextByte == '-';
|
||||
long result = negate ? 0 : nextByte - '0';
|
||||
for (int i = startLocation + 1; i < endLocation; ++i) {
|
||||
nextByte = byteBuffer.get(i);
|
||||
if (nextByte != '.') {
|
||||
result *= 10;
|
||||
result += nextByte - '0';
|
||||
}
|
||||
}
|
||||
return negate ? -result : result;
|
||||
}
|
||||
|
||||
long getValue(byte[] lastLine, int startLocation) {
|
||||
byte nextByte = lastLine[startLocation];
|
||||
boolean negate = nextByte == '-';
|
||||
long result = negate ? 0 : nextByte - '0';
|
||||
for (int i = startLocation + 1; i < lastLine.length; ++i) {
|
||||
nextByte = lastLine[i];
|
||||
if (nextByte != '.') {
|
||||
result *= 10;
|
||||
result += nextByte - '0';
|
||||
}
|
||||
}
|
||||
return negate ? -result : result;
|
||||
}
|
||||
|
||||
String getStationName(MappedByteBuffer byteBuffer, int from, int to) {
|
||||
byte[] bytes = new byte[to - from];
|
||||
byteBuffer.slice(from, to - from).get(0, bytes);
|
||||
return new String(bytes, StandardCharsets.UTF_8);
|
||||
}
|
||||
}
|
||||
|
||||
public static void main(String[] args) throws Exception {
|
||||
String fileName = "measurements.txt";
|
||||
if (args.length > 0 && args[0].length() > 0) {
|
||||
fileName = args[0];
|
||||
}
|
||||
log("InputFile: " + fileName);
|
||||
FileInputStream fileInputStream = new FileInputStream(fileName);
|
||||
int numThreads = 32;
|
||||
if (args.length > 1) {
|
||||
numThreads = Integer.parseInt(args[1]);
|
||||
}
|
||||
log("NumThreads: " + numThreads);
|
||||
FileChannel channel = fileInputStream.getChannel();
|
||||
final long fileSize = channel.size();
|
||||
long remaining_size = fileSize;
|
||||
long chunk_size = Math.min((fileSize + numThreads - 1) / numThreads, Integer.MAX_VALUE - 5);
|
||||
|
||||
ExecutorService executor = Executors.newFixedThreadPool(numThreads);
|
||||
|
||||
long startLocation = 0;
|
||||
ArrayList<Future<HashMap<ByteArrayWrapper, ResultRow>>> results = new ArrayList<>(numThreads);
|
||||
while (remaining_size > 0) {
|
||||
long actualSize = Math.min(chunk_size, remaining_size);
|
||||
results.add(executor.submit(new FileRead(startLocation, toIntExact(actualSize), channel)));
|
||||
remaining_size -= actualSize;
|
||||
startLocation += actualSize;
|
||||
}
|
||||
executor.shutdown();
|
||||
|
||||
// Wait for all threads to finish
|
||||
while (!executor.isTerminated()) {
|
||||
Thread.yield();
|
||||
}
|
||||
log("Finished all threads");
|
||||
fileInputStream.close();
|
||||
HashMap<ByteArrayWrapper, ResultRow> result = new HashMap<>(20000);
|
||||
for (var future : results) {
|
||||
for (var entry : future.get().entrySet()) {
|
||||
result.merge(entry.getKey(), entry.getValue(), ResultRow::merge);
|
||||
}
|
||||
}
|
||||
ResultRow[] finalResult = result.values().toArray(new ResultRow[0]);
|
||||
for (var row : finalResult) {
|
||||
row.toString();
|
||||
}
|
||||
Arrays.sort(finalResult, Comparator.comparing(a -> a.stationString));
|
||||
System.out.println("{" + String.join(", ", Arrays.stream(finalResult).map(ResultRow::toString).toList()) + "}");
|
||||
log("All done!");
|
||||
}
|
||||
|
||||
static void log(String message) {
|
||||
// System.err.println(Instant.now() + "[" + Thread.currentThread().getName() + "]: " + message);
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user