Gamlerhart Last Update: Disabling GC (#636)

* Disable The GC

Cuts off sometimes up to 1 seconds
of runtime on my machine.

* Remove Confusing Byte-Order Parameter

Bytes have no Byte-Order ;)

* Provide More Memory to Run the 10K set

* Fix Comparison Function

calculate_average_gamlerhart.sh

@@ -15,5 +15,5 @@
 #  limitations under the License.
 #
 
-JAVA_OPTS="--enable-preview --add-modules=jdk.incubator.vector"
+JAVA_OPTS="--enable-preview --add-modules=jdk.incubator.vector -XX:+UnlockExperimentalVMOptions -XX:+UseEpsilonGC -Xmx512m -Xlog:all=error"
 java $JAVA_OPTS --class-path target/average-1.0.0-SNAPSHOT.jar dev.morling.onebrc.CalculateAverage_gamlerhart

src/main/java/dev/morling/onebrc/CalculateAverage_gamlerhart.java

@@ -31,8 +31,7 @@
 
 import static java.lang.Double.doubleToRawLongBits;
 import static java.lang.Double.longBitsToDouble;
-import static java.lang.foreign.ValueLayout.JAVA_BYTE;
-import static java.lang.foreign.ValueLayout.JAVA_LONG_UNALIGNED;
+import static java.lang.foreign.ValueLayout.*;
 
 /**
  * Broad experiments in this implementation:
@@ -242,7 +241,7 @@ else if (isSameEntry(file, slotEntry, pos, len)) {
         private boolean isSameEntry(MemorySegment file, long slotEntry, long pos, int len) {
             long keyPos = (slotEntry & MASK_POS) >> SHIFT_POS;
             int keyLen = (int) (slotEntry & MASK_LEN);
-            var isSame = isSame(file, keyPos, pos, len);
+            var isSame = len == keyLen && isSame(file, keyPos, pos, len);
             return isSame;
         }
 
@@ -251,8 +250,8 @@ private static boolean isSame(MemorySegment file, long i1, long i2, int len) {
             var i1len = i1 + vecLen;
             var i2len = i2 + vecLen;
             if (len < vecLen && i1len <= file.byteSize() && i2len <= file.byteSize()) {
-                var v1 = byteVec.fromMemorySegment(file, i1, ByteOrder.BIG_ENDIAN);
-                var v2 = byteVec.fromMemorySegment(file, i2, ByteOrder.BIG_ENDIAN);
+                var v1 = byteVec.fromMemorySegment(file, i1, ByteOrder.nativeOrder());
+                var v2 = byteVec.fromMemorySegment(file, i2, ByteOrder.nativeOrder());
                 var isTrue = v1.compare(VectorOperators.EQ, v2, allTrue.indexInRange(0, len));
                 return isTrue.trueCount() == len;
             }