chore: avoid microtasks when flushing sync

[trueadm]

This has a significant impact on our benchmark suite because we avoid creating microtasks in a sync benchmark. We previously had this logic in the codebase but it was removed in #15348

Main:

{ benchmark: 'sbench_create_signals', time: '401.26', gc_time: '29.60' } { benchmark: 'sbench_create_0to1', time: '8.17', gc_time: '0.00' } { benchmark: 'sbench_create_1to1', time: '29.06', gc_time: '0.59' } { benchmark: 'sbench_create_2to1', time: '27.08', gc_time: '0.52' } { benchmark: 'sbench_create_4to1', time: '25.51', gc_time: '0.61' } { benchmark: 'sbench_create_1000to1', time: '24.78', gc_time: '0.49' } { benchmark: 'sbench_create_1to2', time: '12.27', gc_time: '0.00' } { benchmark: 'sbench_create_1to4', time: '16.14', gc_time: '1.18' } { benchmark: 'sbench_create_1to8', time: '13.43', gc_time: '1.21' } { benchmark: 'sbench_create_1to1000', time: '4.89', gc_time: '0.00' } { benchmark: 'kairo_avoidable_owned', time: '415.52', gc_time: '77.30' } { benchmark: 'kairo_avoidable_unowned', time: '507.39', gc_time: '73.81' } { benchmark: 'kairo_broad_owned', time: '414.50', gc_time: '2.02' } { benchmark: 'kairo_broad_unowned', time: '413.50', gc_time: '2.16' } { benchmark: 'kairo_deep_owned', time: '181.87', gc_time: '1.93' } { benchmark: 'kairo_deep_unowned', time: '806.19', gc_time: '4.01' } { benchmark: 'kairo_diamond_owned', time: '340.28', gc_time: '34.45' } { benchmark: 'kairo_diamond_unowned', time: '434.26', gc_time: '34.75' } { benchmark: 'kairo_triangle_owned', time: '96.85', gc_time: '4.79' } { benchmark: 'kairo_triangle_unowned', time: '198.79', gc_time: '4.57' } { benchmark: 'kairo_mux_owned', time: '298.60', gc_time: '3.77' } { benchmark: 'kairo_mux_unowned', time: '450.16', gc_time: '3.95' } { benchmark: 'kairo_repeated_owned', time: '54.82', gc_time: '5.33' } { benchmark: 'kairo_repeated_unowned', time: '55.61', gc_time: '5.08' } { benchmark: 'kairo_unstable_owned', time: '88.33', gc_time: '5.46' } { benchmark: 'kairo_unstable_unowned', time: '103.47', gc_time: '4.81' } { benchmark: 'mol_bench_owned', time: '231.41', gc_time: '0.75' } { benchmark: 'mol_bench_unowned', time: '248.76', gc_time: '1.18' } Finished reactivity benchmarks. { suite_time: '5902.90', suite_gc_time: '304.32' } 

This PR:

{ benchmark: 'sbench_create_signals', time: '295.67', gc_time: '79.27' } { benchmark: 'sbench_create_0to1', time: '7.83', gc_time: '0.00' } { benchmark: 'sbench_create_1to1', time: '19.93', gc_time: '2.14' } { benchmark: 'sbench_create_2to1', time: '17.41', gc_time: '1.75' } { benchmark: 'sbench_create_4to1', time: '16.30', gc_time: '1.77' } { benchmark: 'sbench_create_1000to1', time: '14.97', gc_time: '2.05' } { benchmark: 'sbench_create_1to2', time: '9.86', gc_time: '0.60' } { benchmark: 'sbench_create_1to4', time: '19.46', gc_time: '6.63' } { benchmark: 'sbench_create_1to8', time: '15.18', gc_time: '3.71' } { benchmark: 'sbench_create_1to1000', time: '4.45', gc_time: '0.00' } { benchmark: 'kairo_avoidable_owned', time: '270.91', gc_time: '4.66' } { benchmark: 'kairo_avoidable_unowned', time: '362.95', gc_time: '5.16' } { benchmark: 'kairo_broad_owned', time: '408.44', gc_time: '0.00' } { benchmark: 'kairo_broad_unowned', time: '407.62', gc_time: '0.00' } { benchmark: 'kairo_deep_owned', time: '175.84', gc_time: '0.00' } { benchmark: 'kairo_deep_unowned', time: '805.32', gc_time: '0.00' } { benchmark: 'kairo_diamond_owned', time: '273.82', gc_time: '2.69' } { benchmark: 'kairo_diamond_unowned', time: '379.19', gc_time: '2.78' } { benchmark: 'kairo_triangle_owned', time: '87.13', gc_time: '0.41' } { benchmark: 'kairo_triangle_unowned', time: '186.83', gc_time: '0.43' } { benchmark: 'kairo_mux_owned', time: '291.71', gc_time: '1.28' } { benchmark: 'kairo_mux_unowned', time: '437.53', gc_time: '1.37' } { benchmark: 'kairo_repeated_owned', time: '44.12', gc_time: '0.21' } { benchmark: 'kairo_repeated_unowned', time: '45.87', gc_time: '0.21' } { benchmark: 'kairo_unstable_owned', time: '76.82', gc_time: '0.53' } { benchmark: 'kairo_unstable_unowned', time: '92.73', gc_time: '0.60' } { benchmark: 'mol_bench_owned', time: '230.92', gc_time: '0.24' } { benchmark: 'mol_bench_unowned', time: '248.28', gc_time: '0.39' } Finished reactivity benchmarks. { suite_time: '5247.09', suite_gc_time: '118.88' } 

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🦋 Changeset detected

Latest commit: 425a8d8

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

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svelte	Patch

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[github-actions]

Playground

pnpm add https://pkg.pr.new/svelte@15855 

[Rich-Harris]

with updated bench:compare

sbench_create_signals time: fastest is b (main) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 446.49ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 439.05ms gc_time: fastest is b (main) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 200.65ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 196.49ms sbench_create_0to1 time: fastest is b (main) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 5.00ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 4.89ms sbench_create_1to1 time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 21.81ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 22.16ms gc_time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 2.72ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 2.73ms sbench_create_2to1 time: fastest is b (main) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 19.73ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 19.48ms gc_time: fastest is b (main) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 2.80ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 2.70ms sbench_create_4to1 time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 18.12ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 18.14ms gc_time: fastest is b (main) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 2.78ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 2.70ms sbench_create_1000to1 time: fastest is b (main) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 16.78ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 16.64ms gc_time: fastest is b (main) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 2.82ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 2.64ms sbench_create_1to2 time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 10.25ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 10.61ms gc_time: fastest is b (main) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 0.65ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 0.61ms sbench_create_1to4 time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 8.36ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 8.78ms gc_time: fastest is b (main) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 0.52ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 0.47ms sbench_create_1to8 time: fastest is b (main) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 6.36ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 6.29ms sbench_create_1to1000 time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 4.65ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 5.04ms kairo_avoidable_owned time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼ 288.04ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 459.60ms gc_time: fastest is a (flush-sync) a: ◼ 6.73ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 111.79ms kairo_avoidable_unowned time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 385.36ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 554.96ms gc_time: fastest is a (flush-sync) a: ◼ 6.74ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 108.98ms kairo_broad_owned time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 431.42ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 434.66ms kairo_broad_unowned time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 431.44ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 433.16ms kairo_deep_owned time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 189.10ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 194.03ms kairo_deep_unowned time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 921.25ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 928.12ms kairo_diamond_owned time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 285.83ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 371.12ms gc_time: fastest is a (flush-sync) a: ◼ 4.03ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 56.06ms kairo_diamond_unowned time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 394.52ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 471.91ms gc_time: fastest is a (flush-sync) a: ◼ 4.06ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 56.02ms kairo_triangle_owned time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 93.83ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 106.47ms gc_time: fastest is a (flush-sync) a: ◼ 0.44ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 8.30ms kairo_triangle_unowned time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 212.52ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 227.08ms gc_time: fastest is a (flush-sync) a: ◼ 0.45ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 9.08ms kairo_mux_owned time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 313.04ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 322.66ms gc_time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼ 2.13ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 5.12ms kairo_mux_unowned time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 470.57ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 481.98ms gc_time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼ 2.18ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 5.36ms kairo_repeated_owned time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 45.66ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 57.89ms gc_time: fastest is a (flush-sync) a: ◼ 0.25ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 7.72ms kairo_repeated_unowned time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 46.50ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 59.80ms gc_time: fastest is a (flush-sync) a: ◼ 0.22ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 7.38ms kairo_unstable_owned time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 79.44ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 91.97ms gc_time: fastest is a (flush-sync) a: ◼◼ 0.75ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 8.64ms kairo_unstable_unowned time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 95.76ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 108.02ms gc_time: fastest is a (flush-sync) a: ◼◼◼ 0.89ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 6.66ms mol_bench_owned time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 278.60ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 281.32ms mol_bench_unowned time: fastest is a (flush-sync) a: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 296.31ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 297.55ms gc_time: fastest is a (flush-sync) a: ◼◼◼◼◼ 0.26ms b: ◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼◼ 1.14ms 

[Rich-Harris]

Not sure why we need a separate boolean and a try-catch wrapper. Simpler version: #15895

[Rich-Harris]

merged #15895, closing