1brc/src/main/java/dev/morling/onebrc/CalculateAverage_kumarsaurav123.java

265 lines
10 KiB
Java

/*
* 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 java.io.IOException;
import java.io.RandomAccessFile;
import java.lang.foreign.Arena;
import java.lang.foreign.MemorySegment;
import java.lang.foreign.ValueLayout;
import java.nio.channels.FileChannel;
import java.nio.charset.StandardCharsets;
import java.util.*;
import java.util.concurrent.*;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.locks.ReentrantLock;
import java.util.stream.Collector;
import java.util.stream.Collectors;
import static java.util.stream.Collectors.groupingBy;
public class CalculateAverage_kumarsaurav123 {
private static final String FILE = "./measurements.txt";
private static AtomicInteger indexCount = new AtomicInteger(0);
private static final ReentrantLock lock = new ReentrantLock();
private static final int MAX_UNIQUE_KEYS = 11000;
private static Map<StringHolder, Integer> indexMap;
private static record Store(double[] min, double[] max, double[] sum,
int[] count) {
private double round(double value) {
return Math.round(value * 10.0) / 10.0;
}
@Override
public String toString() {
return new TreeMap<>(indexMap.entrySet()
.stream()
.map(e -> Map.entry(e.getKey().toString(),
round(min[e.getValue()]) + "/" + round((Math.round(sum[e.getValue()] * 10.0) / 10.0) / count[e.getValue()]) + "/" + round(max[e.getValue()])
))
.collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue))).toString();
}
}
private static record Pair(long start, int size) {
}
public static void main(String[] args) throws IOException, ExecutionException, InterruptedException {
long start = System.currentTimeMillis();
System.out.println(run(FILE));
}
public static String run(String filePath) throws IOException, InterruptedException, ExecutionException {
indexCount = new AtomicInteger(0);
indexMap = new HashMap<>(MAX_UNIQUE_KEYS);
ExecutorService executorService = Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors() * 2);
CompletionService<Store> completionService = new ExecutorCompletionService<>(executorService);
Map<Integer, List<byte[]>> leftOutsMap = new ConcurrentSkipListMap<>();
RandomAccessFile file = new RandomAccessFile(filePath, "r");
long filelength = file.length();
AtomicInteger kk = new AtomicInteger();
MemorySegment memorySegment = file.getChannel().map(FileChannel.MapMode.READ_ONLY, 0, filelength, Arena.ofShared());
int nChunks = 1000;
int pChunkSize = Math.min(Integer.MAX_VALUE, (int) (memorySegment.byteSize() / (1000)));
if (pChunkSize < 100) {
pChunkSize = (int) memorySegment.byteSize();
nChunks = 1;
}
ArrayList<Pair> chunks = createStartAndEnd(pChunkSize, nChunks, memorySegment);
chunks.stream()
.parallel()
.map(p -> {
return createRunnable(memorySegment, p);
})
.forEach(completionService::submit);
executorService.shutdown();
int i = 0;
double[] min = new double[MAX_UNIQUE_KEYS];
double[] max = new double[MAX_UNIQUE_KEYS];
double[] sum = new double[MAX_UNIQUE_KEYS];
int[] count = new int[MAX_UNIQUE_KEYS];
initArray(i, count, min, max, sum);
i = 0;
final Store cureentStore = new Store(min, max, sum, count);
while (i < chunks.size()) {
Store newStore = completionService.take().get();
Map<Integer, StringHolder> reverseMap = indexMap.entrySet()
.stream().collect(Collectors.toMap(Map.Entry::getValue, Map.Entry::getKey));
reverseMap.forEach((key, value) -> {
cureentStore.sum[key] += newStore.sum[key];
cureentStore.count[key] += newStore.count[key];
cureentStore.min[key] = Math.min(cureentStore.min[key],
newStore.min[key]);
cureentStore.max[key] = Math.max(cureentStore.max[key],
newStore.max[key]);
});
i++;
}
return cureentStore.toString();
}
private static void initArray(int i, int[] count, double[] min, double[] max, double[] sum) {
for (; i < count.length; i++) {
min[i] = Double.POSITIVE_INFINITY;
max[i] = Double.NEGATIVE_INFINITY;
sum[i] = 0.0d;
count[i] = 0;
}
}
private static ArrayList<Pair> createStartAndEnd(int chunksize, int nChunks, MemorySegment memorySegment) {
ArrayList<Pair> startSizePairs = new ArrayList<>();
byte eol = "\n".getBytes(StandardCharsets.UTF_8)[0];
long start = 0;
long end = -1;
if (nChunks == 1) {
startSizePairs.add(new Pair(0, chunksize));
return startSizePairs;
}
else {
while (start < memorySegment.byteSize()) {
start = end + 1;
end = Math.min(memorySegment.byteSize() - 1, start + chunksize - 1);
while (memorySegment.get(ValueLayout.JAVA_BYTE, end) != eol) {
end--;
}
startSizePairs.add(new Pair(start, (int) (end - start + 1)));
}
}
return startSizePairs;
}
public static Callable<Store> createRunnable(MemorySegment memorySegment, Pair p) {
return new Callable<Store>() {
@Override
public Store call() {
try {
double[] min = new double[MAX_UNIQUE_KEYS];
double[] max = new double[MAX_UNIQUE_KEYS];
double[] sum = new double[MAX_UNIQUE_KEYS];
int[] count = new int[MAX_UNIQUE_KEYS];
for (int i = 0; i < count.length; i++) {
min[i] = Double.POSITIVE_INFINITY;
max[i] = Double.NEGATIVE_INFINITY;
sum[i] = 0.0d;
count[i] = 0;
}
byte[] allBytes2 = memorySegment.asSlice(p.start, p.size).toArray(ValueLayout.JAVA_BYTE);
byte[] eol = "\n".getBytes(StandardCharsets.UTF_8);
byte[] sep = ";".getBytes(StandardCharsets.UTF_8);
int st = 0;
for (int i = 0; i < allBytes2.length; i++) {
if (allBytes2[i] == eol[0]) {
;
byte[] s2 = new byte[i - st];
System.arraycopy(allBytes2, st, s2, 0, s2.length);
for (int j = 0; j < s2.length; j++) {
if (s2[j] == sep[0]) {
byte[] city = new byte[j];
byte[] value = new byte[s2.length - j - 1];
System.arraycopy(s2, 0, city, 0, city.length);
System.arraycopy(s2, city.length + 1, value, 0, value.length);
double d = getaDouble(value);
StringHolder citys = new StringHolder(city);
Integer index = indexMap.get(citys);
if (Objects.isNull(index)) {
lock.lock();
if (Objects.isNull(indexMap.get(citys))) {
index = indexCount.getAndIncrement();
indexMap.putIfAbsent(citys, index);
}
index = indexMap.get(citys);
lock.unlock();
}
count[index] = count[index] + 1;
max[index] = Math.max(max[index], d);
min[index] = Math.min(min[index], d);
sum[index] = Double.sum(sum[index], d);
break;
}
}
st = i + 1;
}
}
// System.out.println("Task " + kk + "Completed in " + (System.nanoTime() - start));
return new Store(min, max, sum, count);
}
catch (Exception e) {
// throw new RuntimeException(e);
throw e;
}
}
};
}
private static double getaDouble(byte[] value) {
double d = 0.0;
int s = -1;
for (int k = value.length - 1; k >= 0; k--) {
if (value[k] == 45) {
d = d * -1;
}
else if (value[k] == 46) {
}
else {
d = d + (((int) value[k]) - 48) * Math.pow(10, s);
s++;
}
}
return d;
}
static class StringHolder implements Comparable<StringHolder> {
byte[] bytes;
public StringHolder(byte[] bytes) {
this.bytes = bytes;
}
@Override
public String toString() {
return new String(this.bytes);
}
@Override
public int hashCode() {
return Arrays.hashCode(this.bytes);
}
@Override
public boolean equals(Object obj) {
return Arrays.equals(this.bytes, ((StringHolder) obj).bytes);
}
@Override
public int compareTo(StringHolder o) {
return new String(this.bytes).compareTo(new String(o.bytes));
}
}
}