On Fri, 17 Feb 2023 09:50:16 GMT, Sergey Tsypanov <stsypa...@openjdk.org> wrote:
> 1) When `DateTimeFormatter` is reused we don't need to copy > `availableZoneIds` and allocate `nonRegionIds` as PrefixTree can be taken > from cache. In the related benchmark allocation of `HashSet` takes ~93% of > all time, so avoiding it should bring some improvement for cases when we > reuse `DateTimeFormatter` to parse a string into `ZoneDateTime` >  > > 2) `DateTimeFormatter` is mostly used with one locale, so `cachedTree` and > `cachedTreeCI` can have predefined size. > > > @State(Scope.Thread) > @BenchmarkMode(Mode.AverageTime) > @OutputTimeUnit(TimeUnit.NANOSECONDS) > public class DateTimeFormatterBenchmark { > > private static final DateTimeFormatter df = new > DateTimeFormatterBuilder().appendPattern("yyyy:MM:dd:HH:mm:v").toFormatter(); > private static final String TEXT = "2015:03:10:12:13:ECT"; > > @Setup > public void setUp() { > ZonedDateTime.parse(TEXT, df); > } > > @Benchmark > public ZonedDateTime parse() { > return ZonedDateTime.parse(TEXT, df); > } > } Looks like a nice fix to me. test/micro/org/openjdk/bench/java/time/format/ZonedDateTimeFormatterBenchmark.java line 23: > 21: * questions. > 22: */ > 23: package time.format; package should be `org.openjdk.bench.java.time.format`? ------------- Changes requested by naoto (Reviewer). PR Review: https://git.openjdk.org/jdk/pull/12612#pullrequestreview-1361520443 PR Review Comment: https://git.openjdk.org/jdk/pull/12612#discussion_r1150894573
