On Tue, 27 Jun 2023 13:57:31 GMT, Chen Liang <li...@openjdk.org> wrote:
>> This patch implements lazy initialization for VarHandle working on static >> fields. It has a good initial call performance. >> >> We introduce a new internal API, `target()` to unpack a lazy VarHandle in VH >> implementation methods. If called via MethodHandle, a barrier is added in >> the MethodHandle instead. >> >> The new test ensures the correctness of Lazy VH for both direct and indirect >> invocation; the performance of MethodHandle version of lazy VH is not yet >> tested. >> >> >> Benchmark Mode Cnt Score >> Error Units >> LazyStaticColdStart.methodHandleCreateEager ss 10 41.490 ± >> 12.331 us/op >> LazyStaticColdStart.methodHandleCreateLazy ss 10 21.810 ± >> 16.964 us/op >> LazyStaticColdStart.methodHandleInitializeCallEager ss 10 57.860 ± >> 13.738 us/op >> LazyStaticColdStart.methodHandleInitializeCallLazy ss 10 93.300 ± >> 18.858 us/op >> LazyStaticColdStart.varHandleCreateEager ss 10 39.860 ± >> 9.362 us/op >> LazyStaticColdStart.varHandleCreateLazy ss 10 17.630 ± >> 1.111 us/op >> LazyStaticColdStart.varHandleInitializeCallEager ss 10 123.170 ± >> 62.468 us/op >> LazyStaticColdStart.varHandleInitializeCallLazy ss 10 105.390 ± >> 41.815 us/op > > Chen Liang has updated the pull request incrementally with one additional > commit since the last revision: > > Rollback VHG changes Latest update looks very good, i like how it has got simpler and therefore easier to understand. I agree with a focus on the correctness for the MHs, as it is quite hard to reason about all this. The initializing MHs should optimize, it just takes more work to do so. I shall provide some minor comments inline. ------------- PR Comment: https://git.openjdk.org/jdk/pull/13821#issuecomment-1610190790