Playground/1brc
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Reverting ByteBuffer idea, using Thomas's trick instead. (#538)

Browse Source
This commit is contained in:
Roy van Rijn 2024-01-21 11:15:07 -08:00 committed by GitHub
parent d0a28599c2
commit d8b071c878
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
2 changed files with 37 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
prepare_royvanrijn.sh
View File

@ -16,7 +16,7 @@
#
source "$HOME/.sdkman/bin/sdkman-init.sh"
sdk use java 21.0.1-graal 1>&2
sdk use java 21.0.2-graal 1>&2
# ./mvnw clean verify removes target/ and will re-trigger native image creation.
if [ ! -f target/CalculateAverage_royvanrijn_image ]; then

44
src/main/java/dev/morling/onebrc/CalculateAverage_royvanrijn.java
View File

@ -15,12 +15,15 @@
*/
package dev.morling.onebrc;
import java.io.IOException;
import java.lang.foreign.Arena;
import java.lang.reflect.Field;
import java.nio.channels.FileChannel;
import java.nio.charset.StandardCharsets;
import java.nio.file.Path;
import java.nio.file.StandardOpenOption;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.stream.Collectors;
@ -102,8 +105,27 @@ public class CalculateAverage_royvanrijn {
private static final int TABLE_SIZE = 1 << 19; // large enough for the contest.
private static final int TABLE_MASK = (TABLE_SIZE - 1);
public static void main(String[] args) throws Exception {
// Idea of thomaswue, don't wait for slow unmap:
private static void spawnWorker() throws IOException {
ProcessHandle.Info info = ProcessHandle.current().info();
ArrayList<String> workerCommand = new ArrayList<>();
info.command().ifPresent(workerCommand::add);
info.arguments().ifPresent(args -> workerCommand.addAll(Arrays.asList(args)));
workerCommand.add("--worker");
new ProcessBuilder()
.command(workerCommand)
.inheritIO()
.redirectOutput(ProcessBuilder.Redirect.PIPE)
.start()
.getInputStream()
.transferTo(System.out);
}
public static void main(String[] args) throws Exception {
if (args.length == 0 || !("--worker".equals(args[0]))) {
spawnWorker();
return;
}
// Calculate input segments.
final FileChannel fileChannel = FileChannel.open(Path.of(FILE), StandardOpenOption.READ);
final long fileSize = fileChannel.size();
@ -159,7 +181,7 @@ public class CalculateAverage_royvanrijn {
.collect(Collectors.joining(", ")));
System.out.println("}");
// System.out.println(measurements.entrySet().stream().mapToLong(e -> UNSAFE.getInt(e.getValue(), ENTRY_COUNT + Unsafe.ARRAY_BYTE_BASE_OFFSET)).sum());
System.out.close(); // close the stream to stop
}
private static byte[] fillEntry(final byte[] entry, final long fromAddress, final int length, final int temp) {
@ -176,15 +198,15 @@ public class CalculateAverage_royvanrijn {
int entryMin = UNSAFE.getInt(entry, ENTRY_MIN);
int entryMax = UNSAFE.getInt(entry, ENTRY_MAX);
entryMin = Math.min(temp, entryMin);
entryMax = Math.max(temp, entryMax);
long entrySum = UNSAFE.getLong(entry, ENTRY_SUM) + temp;
int entryCount = UNSAFE.getInt(entry, ENTRY_COUNT) + 1;
UNSAFE.putInt(entry, ENTRY_MIN, entryMin);
UNSAFE.putInt(entry, ENTRY_MAX, entryMax);
if (temp < entryMin) {
UNSAFE.putInt(entry, ENTRY_MIN, temp);
}
else if (temp > entryMax) {
UNSAFE.putInt(entry, ENTRY_MAX, temp);
}
UNSAFE.putInt(entry, ENTRY_COUNT, entryCount);
UNSAFE.putLong(entry, ENTRY_SUM, entrySum);
}
@ -435,6 +457,8 @@ public class CalculateAverage_royvanrijn {
reader.processStart();
if (!reader.readFirst()) {
// Found delimiter in first 8 bytes:
int temperature = reader.processEndAndGetTemperature();
// Find or insert the entry:
@ -462,6 +486,7 @@ public class CalculateAverage_royvanrijn {
reader.processName();
if (!reader.readNext()) {
// Found delimiter in 8-16 bytes:
int temperature = reader.processEndAndGetTemperature();
@ -490,6 +515,8 @@ public class CalculateAverage_royvanrijn {
reader.processName();
if (!reader.readNext()) {
// Found delimiter in 16-24 bytes:
int temperature = reader.processEndAndGetTemperature();
// Find or insert the entry:
@ -515,6 +542,7 @@ public class CalculateAverage_royvanrijn {
}
else {
// Need more than 24 bytes:
reader.processName();
while (reader.readNext()) {