go encoding/json: optimize field sorting with slices and cmp

Refactor field sorting in typeFields to use slices.SortFunc and cmp.Compare, resulting in performance improvements in cache misses and slight increases in hit latency. Memory allocation and operation counts also reduced significantly for cache misses.

goos: darwin goarch: arm64 pkg: encoding/json cpu: Apple M2 Max │ old.txt │ new.txt │ │ sec/op │ sec/op vs base │ TypeFieldsCache/MissTypes1-12 5.068µ ± 2% 5.032µ ± 1% ~ (p=0.055 n=10) TypeFieldsCache/MissTypes10-12 15.22µ ± 2% 14.79µ ± 2% -2.84% (p=0.000 n=10) TypeFieldsCache/MissTypes100-12 98.40µ ± 3% 94.72µ ± 1% -3.73% (p=0.002 n=10) TypeFieldsCache/MissTypes1000-12 860.3µ ± 3% 840.7µ ± 1% ~ (p=0.105 n=10) TypeFieldsCache/MissTypes10000-12 8.092m ± 3% 7.987m ± 4% ~ (p=0.280 n=10) TypeFieldsCache/MissTypes100000-12 80.90m ± 9% 80.62m ± 2% ~ (p=0.631 n=10) TypeFieldsCache/MissTypes1000000-12 1009.5m ± 7% 933.8m ± 7% -7.50% (p=0.011 n=10) TypeFieldsCache/HitTypes1-12 1.554n ± 3% 1.617n ± 3% +4.05% (p=0.004 n=10) TypeFieldsCache/HitTypes10-12 1.575n ± 1% 1.624n ± 6% +3.14% (p=0.000 n=10) TypeFieldsCache/HitTypes100-12 1.566n ± 1% 1.627n ± 5% +3.86% (p=0.000 n=10) TypeFieldsCache/HitTypes1000-12 1.526n ± 4% 1.596n ± 3% +4.55% (p=0.001 n=10) TypeFieldsCache/HitTypes10000-12 1.506n ± 0% 1.573n ± 3% +4.41% (p=0.000 n=10) TypeFieldsCache/HitTypes100000-12 1.480n ± 1% 1.529n ± 7% +3.35% (p=0.001 n=10) TypeFieldsCache/HitTypes1000000-12 1.473n ± 2% 1.468n ± 2% ~ (p=0.739 n=10) geomean 1.371µ 1.374µ +0.25%

                                │     old.txt     │                new.txt                 │
                                │      B/op       │     B/op       vs base                 │

TypeFieldsCache/MissTypes1-12 2.023Ki ± 0% 2.000Ki ± 0% -1.16% (p=0.000 n=10) TypeFieldsCache/MissTypes10-12 10.95Ki ± 0% 10.71Ki ± 0% -2.17% (p=0.000 n=10) TypeFieldsCache/MissTypes100-12 101.91Ki ± 0% 99.53Ki ± 0% -2.34% (p=0.000 n=10) TypeFieldsCache/MissTypes1000-12 1044.3Ki ± 0% 1020.8Ki ± 0% -2.25% (p=0.000 n=10) TypeFieldsCache/MissTypes10000-12 9.957Mi ± 0% 9.730Mi ± 0% -2.29% (p=0.000 n=10) TypeFieldsCache/MissTypes100000-12 97.79Mi ± 0% 95.50Mi ± 0% -2.34% (p=0.000 n=10) TypeFieldsCache/MissTypes1000000-12 1018.4Mi ± 0% 995.5Mi ± 0% -2.25% (p=0.000 n=10) TypeFieldsCache/HitTypes1-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ TypeFieldsCache/HitTypes10-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ TypeFieldsCache/HitTypes100-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ TypeFieldsCache/HitTypes1000-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ TypeFieldsCache/HitTypes10000-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ TypeFieldsCache/HitTypes100000-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ TypeFieldsCache/HitTypes1000000-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ geomean ² -1.06% ² ¹ all samples are equal ² summaries must be >0 to compute geomean

                                │    old.txt    │               new.txt                │
                                │   allocs/op   │  allocs/op   vs base                 │

TypeFieldsCache/MissTypes1-12 46.00 ± 0% 45.00 ± 0% -2.17% (p=0.000 n=10) TypeFieldsCache/MissTypes10-12 215.0 ± 0% 205.0 ± 0% -4.65% (p=0.000 n=10) TypeFieldsCache/MissTypes100-12 1.845k ± 0% 1.745k ± 0% -5.42% (p=0.000 n=10) TypeFieldsCache/MissTypes1000-12 18.08k ± 0% 17.08k ± 0% -5.53% (p=0.000 n=10) TypeFieldsCache/MissTypes10000-12 180.3k ± 0% 170.3k ± 0% -5.55% (p=0.000 n=10) TypeFieldsCache/MissTypes100000-12 1.804M ± 0% 1.704M ± 0% -5.54% (p=0.000 n=10) TypeFieldsCache/MissTypes1000000-12 18.04M ± 0% 17.04M ± 0% -5.54% (p=0.000 n=10) TypeFieldsCache/HitTypes1-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ TypeFieldsCache/HitTypes10-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ TypeFieldsCache/HitTypes100-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ TypeFieldsCache/HitTypes1000-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ TypeFieldsCache/HitTypes10000-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ TypeFieldsCache/HitTypes100000-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ TypeFieldsCache/HitTypes1000000-12 0.000 ± 0% 0.000 ± 0% ~ (p=1.000 n=10) ¹ geomean ² -2.49% ² ¹ all samples are equal ² summaries must be >0 to compute geomean

Apr 26 '24 03:04 aimuz

This PR (HEAD: d16772d4fb44f76e2688e15f1bdfc7db14bb55c6) has been imported to Gerrit for code review.

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Apr 26 '24 03:04 gopherbot

Message from Gopher Robot:

Patch Set 1:

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