From 22b960ada294a87d5cf60c2dc1b13585287cab73 Mon Sep 17 00:00:00 2001
From: Samuel Yvon
Date: Fri, 12 Jan 2024 11:16:13 -0800
Subject: [PATCH] Graal Native for SamuelYvon (#332)
* Graal Native
* I need a GC :(
* Fix slash lolz
* Fix god damn output lol
I forgot java :D
* Custom hash, custom key
* More optimisations
* I don't need "optimize-build"
I don't care about image size! :D
---
calculate_average_SamuelYvon.sh | 17 ++-
prepare_SamuelYvon.sh | 17 +++
....java => CalculateAverage_SamuelYvon.java} | 131 +++++++++++++++---
3 files changed, 144 insertions(+), 21 deletions(-)
rename src/main/java/dev/morling/onebrc/{CalculateAverage_samuelyvon.java => CalculateAverage_SamuelYvon.java} (62%)
diff --git a/calculate_average_SamuelYvon.sh b/calculate_average_SamuelYvon.sh
index da03382..046b8b0 100755
--- a/calculate_average_SamuelYvon.sh
+++ b/calculate_average_SamuelYvon.sh
@@ -15,5 +15,18 @@
# limitations under the License.
#
-JAVA_OPTS="--enable-preview"
-java $JAVA_OPTS --class-path target/average-1.0.0-SNAPSHOT.jar dev.morling.onebrc.CalculateAverage_samuelyvon
+# THIS IS A DIRECT COPY OF royvanrijn's CALCULATE SCRIPT; I AM NOT FAMILIAR WITH AOT STUFF ON JAVA.
+# THANKS royvanrijn!!
+
+if [ -f target/CalculateAverage_SamuelYvon_image ]; then
+ echo "Picking up existing native image 'target/CalculateAverage_SamuelYvon_image', delete the file to select JVM mode." 1>&2
+ target/CalculateAverage_SamuelYvon_image
+else
+ JAVA_OPTS="--enable-preview -XX:+UnlockExperimentalVMOptions -XX:+TrustFinalNonStaticFields -dsa -XX:+UseNUMA"
+ if [[ ! "$(uname -s)" = "Darwin" ]]; then
+ # On OS/X, my machine, this errors:
+ JAVA_OPTS="$JAVA_OPTS -XX:+UseTransparentHugePages"
+ fi
+ echo "Choosing to run the app in JVM mode as no native image was found, use additional_build_step_SamuelYvon.sh to generate." 1>&2
+ java $JAVA_OPTS --class-path target/average-1.0.0-SNAPSHOT.jar dev.morling.onebrc.CalculateAverage_SamuelYvon
+fi
diff --git a/prepare_SamuelYvon.sh b/prepare_SamuelYvon.sh
index f83a3ff..11fe5e8 100755
--- a/prepare_SamuelYvon.sh
+++ b/prepare_SamuelYvon.sh
@@ -15,5 +15,22 @@
# limitations under the License.
#
+# THIS IS A DIRECT COPY OF royvanrijn's PREPARE SCRIPT; I AM NOT FAMILIAR WITH AOT STUFF ON JAVA.
+# THANKS royvanrijn!!
+
source "$HOME/.sdkman/bin/sdkman-init.sh"
sdk use java 21.0.1-graal 1>&2
+
+# ./mvnw clean verify removes target/ and will re-trigger native image creation.
+if [ ! -f target/CalculateAverage_SamuelYvon_image ]; then
+
+ JAVA_OPTS="--enable-preview -dsa"
+
+ # No vector API because it does not link :(
+# JAVA_OPTS="--enable-preview -dsa --add-modules jdk.incubator.vector"
+
+# Enable the GC because I need memory :D
+ NATIVE_IMAGE_OPTS="--gc=G1 -O3 -march=native --strict-image-heap $JAVA_OPTS"
+
+ native-image $NATIVE_IMAGE_OPTS -cp target/average-1.0.0-SNAPSHOT.jar -o target/CalculateAverage_SamuelYvon_image dev.morling.onebrc.CalculateAverage_SamuelYvon
+fi
diff --git a/src/main/java/dev/morling/onebrc/CalculateAverage_samuelyvon.java b/src/main/java/dev/morling/onebrc/CalculateAverage_SamuelYvon.java
similarity index 62%
rename from src/main/java/dev/morling/onebrc/CalculateAverage_samuelyvon.java
rename to src/main/java/dev/morling/onebrc/CalculateAverage_SamuelYvon.java
index 10a2179..45ffd0d 100644
--- a/src/main/java/dev/morling/onebrc/CalculateAverage_samuelyvon.java
+++ b/src/main/java/dev/morling/onebrc/CalculateAverage_SamuelYvon.java
@@ -15,6 +15,8 @@
*/
package dev.morling.onebrc;
+//import jdk.incubator.vector.ByteVector;
+
import java.io.IOException;
import java.io.RandomAccessFile;
import java.nio.MappedByteBuffer;
@@ -52,7 +54,7 @@ import java.util.stream.Collectors;
* 2024-01-09: Naive multi-threaded, no floats, manual line parsing
*
*/
-public class CalculateAverage_samuelyvon {
+public class CalculateAverage_SamuelYvon {
private static final String FILE = "./measurements.txt";
@@ -60,15 +62,21 @@ public class CalculateAverage_samuelyvon {
private static final byte SEMICOL = 0x3B;
+ private static final byte DOT = '.';
+
private static final byte MINUS = '-';
private static final byte ZERO = '0';
+ private static final String SLASH_S = "/";
+
private static final byte NEWLINE = '\n';
// The minimum line length in bytes (over-egg.)
private static final int MIN_LINE_LENGTH_BYTES = 200;
+ private static final int DJB2_INIT = 5381;
+
/**
* Branchless min (unprecise for large numbers, but good enough)
*
@@ -91,25 +99,84 @@ public class CalculateAverage_samuelyvon {
return b + (diff & dsgn);
}
+ /**
+ * A magic key that contains references to the String and where it's located in memory
+ */
+ private static final class StationName {
+ private final int hash;
+
+ private final byte[] value;
+
+ private StationName(int hash, MappedByteBuffer backing, int pos, int len) {
+ this.hash = hash;
+ this.value = new byte[len];
+ backing.get(pos, this.value);
+ }
+
+ @Override
+ public int hashCode() {
+ return hash;
+ }
+
+ @SuppressWarnings("EqualsWhichDoesntCheckParameterClass")
+ @Override
+ public boolean equals(Object obj) {
+ // Should NEVER be true
+ // if (!(obj instanceof StationName)) {
+ // return false;
+ // }
+ StationName other = (StationName) obj;
+
+ if (this.value.length != other.value.length) {
+ return false;
+ }
+
+ // Byte for byte compare. This actually is a bug! I'm assuming the input
+ // is UTF-8 normalized, which in real life would probably not be the case.
+ // TODO: SIMD?
+ return Arrays.equals(this.value, other.value);
+ }
+
+ @Override
+ public String toString() {
+ return new String(this.value, StandardCharsets.UTF_8);
+ }
+ }
+
private static class StationMeasureAgg {
private int min;
private int max;
private long sum;
private long count;
- private final String city;
+ private final StationName station;
- public StationMeasureAgg(String city) {
+ private String memoizedName;
+
+ public StationMeasureAgg(StationName name) {
// Actual numbers are between -99.9 and 99.9, but we *10 to avoid float
- this.city = city;
+ this.station = name;
min = 1000;
max = -1000;
sum = 0;
count = 0;
}
+ @Override
+ public int hashCode() {
+ return this.station.hash;
+ }
+
+ /**
+ * Get the city name, but also memoized it to avoid building it multiple times
+ *
+ * @return the city name
+ */
public String city() {
- return this.city;
+ if (null == this.memoizedName) {
+ this.memoizedName = station.toString();
+ }
+ return this.memoizedName;
}
public StationMeasureAgg mergeWith(StationMeasureAgg other) {
@@ -135,27 +202,38 @@ public class CalculateAverage_samuelyvon {
double min = Math.round((double) this.min) / 10.0;
double max = Math.round((double) this.max) / 10.0;
double mean = Math.round((((double) this.sum / this.count))) / 10.0;
- return min + "/" + mean + "/" + max;
+ return min + SLASH_S + mean + SLASH_S + max;
+ }
+
+ public StationName station() {
+ return this.station;
}
}
- private static HashMap parseChunk(MappedByteBuffer chunk) {
- HashMap m = HashMap.newHashMap(MAX_STATIONS);
+ private static HashMap parseChunk(MappedByteBuffer chunk) {
+ HashMap m = HashMap.newHashMap(MAX_STATIONS);
int i = 0;
while (i < chunk.limit()) {
int j = i;
+
+ int hash = DJB2_INIT;
+
+ // Implement a version of djb2 while we read until the semi, we read anyways
for (; j < chunk.limit(); ++j) {
- // TODO: Could compute a hash here, store a byte array, and decode UTF-8 at the
- // latest moment.
- if (chunk.get(j) == SEMICOL) {
+ byte b = chunk.get(j);
+
+ if (b == SEMICOL) {
break;
}
+
+ // How will this behave in java? Why do I get no control OF SIGNEDNESS FFS
+ // Can I assume int is 32 bits? What is this language! In Java 1.7 it could be 16 bits?
+ // Apparently not anymore??
+ hash = (((hash << 5) + hash) + b);
}
- byte[] backingNameArray = new byte[j - i];
- chunk.get(i, backingNameArray);
- String name = new String(backingNameArray, StandardCharsets.UTF_8);
+ StationName name = new StationName(hash, chunk, i, j - i);
// Skip the `;`
j++;
@@ -167,7 +245,7 @@ public class CalculateAverage_samuelyvon {
for (j = j + (neg ? 1 : 0); j < chunk.limit(); ++j) {
temp *= 10;
byte c = chunk.get(j);
- if (c != '.') {
+ if (c != DOT) {
temp += (char) (c - ZERO);
}
else {
@@ -181,7 +259,7 @@ public class CalculateAverage_samuelyvon {
i = j + 1;
- while (chunk.get(i++) != '\n')
+ while (chunk.get(i++) != NEWLINE)
;
if (neg)
@@ -241,9 +319,24 @@ public class CalculateAverage_samuelyvon {
var fileChunks = getFileChunks();
// Map per core, giving the non-overlapping memory slices
- final Map sortedMeasures = fileChunks.parallelStream().map(CalculateAverage_samuelyvon::parseChunk)
- .flatMap(x -> x.values().stream()).collect(Collectors.toMap(StationMeasureAgg::city, x -> x, StationMeasureAgg::mergeWith, TreeMap::new));
+ final Map allMeasures = fileChunks.parallelStream().map(CalculateAverage_SamuelYvon::parseChunk).flatMap(x -> x.values().stream())
+ .collect(Collectors.toMap(StationMeasureAgg::station, x -> x, StationMeasureAgg::mergeWith, HashMap::new));
- System.out.println(sortedMeasures);
+ // Give a capacity that should never be gone past
+ StringBuilder sb = new StringBuilder(allMeasures.size() * (100 + 4 + 20));
+ sb.append('{');
+
+ allMeasures.values().stream().sorted(Comparator.comparing(StationMeasureAgg::city)).forEach(x -> {
+ sb.append(x.city());
+ sb.append('=');
+ sb.append(x);
+ sb.append(", ");
+ });
+
+ sb.delete(sb.length() - 2, sb.length()); // delete trailing comma and space
+
+ sb.append('}');
+
+ System.out.println(sb);
}
}