On Sun, 17 Sep 2023 16:01:33 GMT, 温绍锦 <d...@openjdk.org> wrote:
> @cl4es made performance optimizations for the simple specifiers of > String.format in PR https://github.com/openjdk/jdk/pull/2830. Based on the > same idea, I continued to make improvements. I made patterns like %2d %02d > also be optimized. > > The following are the test results based on MacBookPro M1 Pro: > > > -Benchmark Mode Cnt Score Error Units > -StringFormat.complexFormat avgt 15 1862.233 ? 217.479 ns/op > -StringFormat.int02Format avgt 15 312.491 ? 26.021 ns/op > -StringFormat.intFormat avgt 15 84.432 ? 4.145 ns/op > -StringFormat.longFormat avgt 15 87.330 ? 6.111 ns/op > -StringFormat.stringFormat avgt 15 63.985 ? 11.366 ns/op > -StringFormat.stringIntFormat avgt 15 87.422 ? 0.147 ns/op > -StringFormat.widthStringFormat avgt 15 250.740 ? 32.639 ns/op > -StringFormat.widthStringIntFormat avgt 15 312.474 ? 16.309 ns/op > > +Benchmark Mode Cnt Score Error Units > +StringFormat.complexFormat avgt 15 740.626 ? 66.671 ns/op > (+151.45) > +StringFormat.int02Format avgt 15 131.049 ? 0.432 ns/op > (+138.46) > +StringFormat.intFormat avgt 15 67.229 ? 4.155 ns/op > (+25.59) > +StringFormat.longFormat avgt 15 66.444 ? 0.614 ns/op > (+31.44) > +StringFormat.stringFormat avgt 15 62.619 ? 4.652 ns/op (+2.19) > +StringFormat.stringIntFormat avgt 15 89.606 ? 13.966 ns/op (-2.44) > +StringFormat.widthStringFormat avgt 15 52.462 ? 15.649 ns/op > (+377.95) > +StringFormat.widthStringIntFormat avgt 15 101.814 ? 3.147 ns/op > (+206.91) I enhanced parse fast-path to support more specifiers, including: % flag_1 width_1 % flag_2 % width_2 % width_1 . precesion_1 now benchmark on macbook m1 pro result is: -Benchmark Mode Cnt Score Error Units (optimized) -StringFormat.complexFormat avgt 15 2049.387 ? 121.539 ns/op -StringFormat.flags2Format avgt 15 430.964 ? 2.414 ns/op -StringFormat.flagsFormat avgt 15 257.851 ? 23.833 ns/op -StringFormat.stringFormat avgt 15 63.564 ? 10.490 ns/op -StringFormat.stringIntFormat avgt 15 88.111 ? 0.678 ns/op -StringFormat.width2Format avgt 15 349.304 ? 31.349 ns/op -StringFormat.width2PrecisionFormat avgt 15 464.621 ? 53.918 ns/op -StringFormat.widthFormat avgt 15 301.997 ? 34.974 ns/op -StringFormat.widthPrecisionFormat avgt 15 484.526 ? 38.098 ns/op -StringFormat.widthStringFormat avgt 15 235.421 ? 32.955 ns/op -StringFormat.widthStringIntFormat avgt 15 315.178 ? 15.154 ns/op +Benchmark Mode Cnt Score Error Units +StringFormat.complexFormat avgt 15 702.407 ? 85.481 ns/op (+191.77) +StringFormat.flags2Format avgt 15 329.551 ? 1.610 ns/op (+30.78) +StringFormat.flagsFormat avgt 15 125.798 ? 1.109 ns/op (+104.98) +StringFormat.stringFormat avgt 15 60.029 ? 6.275 ns/op (+5.89) +StringFormat.stringIntFormat avgt 15 89.020 ? 0.575 ns/op (-1.03) +StringFormat.width2Format avgt 15 135.743 ? 0.643 ns/op (+157.33) +StringFormat.width2PrecisionFormat avgt 15 351.408 ? 21.031 ns/op (+32.22) +StringFormat.widthFormat avgt 15 208.843 ? 47.504 ns/op (+44.61) +StringFormat.widthPrecisionFormat avgt 15 354.375 ? 67.314 ns/op (+36.73) +StringFormat.widthStringFormat avgt 15 74.846 ? 19.604 ns/op (+214.55) +StringFormat.widthStringIntFormat avgt 15 101.638 ? 0.961 ns/op (+210.10) > I was worried this would sprawl out more, but perhaps ~230 lines of code is a > reasonable extra weight to make the long tail of `String.format`'s regex-free. > > I was going to comment that the flag parsing was broken in > [f303f29](https://github.com/openjdk/jdk/commit/f303f2959d108d993dc03e86a27ef42bb892647f) > but it seems that it was fixed in the latest. I think we need to make a > review pass over all existing tests to make sure all imaginable variants are > covered. > > The parser code also ought to be shared between `Formatter` and > `FormatProcessor` so that there's a single source of truth going forward. The codes of Formatter and FormatProcessor have been regex-free. There are many changes and require more detailed review. ------------- PR Comment: https://git.openjdk.org/jdk/pull/15776#issuecomment-1723733247 PR Comment: https://git.openjdk.org/jdk/pull/15776#issuecomment-1730164585
