On Mon, 19 Oct 2020 06:57:24 GMT, Aleksey Shipilev <sh...@openjdk.org> wrote:
>> This is fork off the SizeOf JEP, JDK-8249196. There is already the entry >> point in JDK that can use the intrinsic like >> this: `Instrumentation.getInstanceSize`. Therefore, we can implement the >> C1/C2 intrinsic now, hook it up to >> `Instrumentation`, and let the tools use that fast path today. With this >> patch, JOL is able to be close to >> `deepSizeOf` implementation from SizeOf JEP. >> Example performance improvements for sizing up a custom linked list: >> >> Benchmark (size) Mode Cnt Score Error Units >> >> # Default >> LinkedChainBench.linkedChain 1 avgt 5 705.835 ± 8.051 ns/op >> LinkedChainBench.linkedChain 10 avgt 5 3148.874 ± 37.856 ns/op >> LinkedChainBench.linkedChain 100 avgt 5 28693.256 ± 142.254 ns/op >> LinkedChainBench.linkedChain 1000 avgt 5 290161.590 ± 4594.631 ns/op >> >> # Instrumentation attached, no intrinsics >> LinkedChainBench.linkedChain 1 avgt 5 159.659 ± 19.238 ns/op >> LinkedChainBench.linkedChain 10 avgt 5 717.659 ± 22.540 ns/op >> LinkedChainBench.linkedChain 100 avgt 5 7739.394 ± 111.683 ns/op >> LinkedChainBench.linkedChain 1000 avgt 5 80724.238 ± 2887.794 ns/op >> >> # Instrumentation attached, new intrinsics >> LinkedChainBench.linkedChain 1 avgt 5 95.254 ± 0.808 ns/op >> LinkedChainBench.linkedChain 10 avgt 5 261.564 ± 8.524 ns/op >> LinkedChainBench.linkedChain 100 avgt 5 3367.192 ± 21.128 ns/op >> LinkedChainBench.linkedChain 1000 avgt 5 34148.851 ± 373.080 ns/op > > Aleksey Shipilev has refreshed the contents of this pull request, and > previous commits have been removed. The > incremental views will show differences compared to the previous content of > the PR. test/jdk/java/lang/instrument/GetObjectSizeTest.java line 2: > 1: /* > 2: * Copyright (c) 2020, Red Hat, Inc. All rights reserved. You can't replace Copyright lines of one company with other. ------------- PR: https://git.openjdk.java.net/jdk/pull/650
