> `ZoneOffset` instances are cached by the `ZoneOffset` class itself for values > in the range [-18h, 18h] for each second that is on an even quarter of an > hour (i.e. at most 2*18*4+1 = 145 values). > > Instead of using a `ConcurrentHashMap` for caching instanced, we could > instead use an `AtomicReferenceArray` with direct slot value access for said > even seconds. This will improve performance and reduce the number of object > even though the backing array will go from an initial 32 in the CHM to an > initial/final 145 in the ARA. The CHM will contain much more objects and > array slots for typical numbers of entries in the cache and will compute > hash/bucket/collision on the hot code path for each cache access.
Per Minborg has updated the pull request incrementally with two additional commits since the last revision: - Simplify benchmark - Add benchmark ------------- Changes: - all: https://git.openjdk.org/jdk/pull/12346/files - new: https://git.openjdk.org/jdk/pull/12346/files/5a8e9720..562885c7 Webrevs: - full: https://webrevs.openjdk.org/?repo=jdk&pr=12346&range=03 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=12346&range=02-03 Stats: 70 lines in 1 file changed: 70 ins; 0 del; 0 mod Patch: https://git.openjdk.org/jdk/pull/12346.diff Fetch: git fetch https://git.openjdk.org/jdk pull/12346/head:pull/12346 PR: https://git.openjdk.org/jdk/pull/12346
