On Sat, 1 Jul 2023 19:05:23 GMT, Sergey Tsypanov <stsypa...@openjdk.org> wrote:
>> The below benchmark files have scaling issues due to cache contention and >> leads to poor scaling when run on multiple threads. The patch sets the scope >> from benchmark level to thread level to fix the issue: >> - org/openjdk/bench/java/io/DataOutputStreamTest.java >> - org/openjdk/bench/java/lang/ArrayCopyObject.java >> - org/openjdk/bench/java/lang/ArrayFiddle.java >> - org/openjdk/bench/java/time/format/DateTimeFormatterBench.java >> - org/openjdk/bench/jdk/incubator/vector/IndexInRangeBenchmark.java >> - org/openjdk/bench/jdk/incubator/vector/MemorySegmentVectorAccess.java >> - org/openjdk/bench/jdk/incubator/vector/StoreMaskedBenchmark.java >> - org/openjdk/bench/jdk/incubator/vector/StoreMaskedIOOBEBenchmark.java >> - org/openjdk/bench/vm/compiler/ArrayFill.java >> - org/openjdk/bench/vm/compiler/IndexVector.java >> >> Also removing the static scope for variables in >> org/openjdk/bench/jdk/incubator/vector/VectorFPtoIntCastOperations.java for >> better scaling. >> >> Please review and share your feedback. >> >> Thanks, >> Swati > > test/micro/org/openjdk/bench/java/lang/ArrayCopyObject.java line 64: > >> 62: } >> 63: >> 64: @State(Scope.Thread) > > Are you sure it makes sense as in `main()` method we set `fork(1)` so there's > only one thread running the benchmark? AFAIK fork value specifies number of times harness should [fork](https://javadoc.io/doc/org.openjdk.jmh/jmh-core/0.6/org/openjdk/jmh/annotations/Fork.html). Also the change is setting scope to thread level not controlling the number of threads. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/14746#discussion_r1251459004
