Optimize dev rebuild defaults

[ScriptedAlchemy]

Summary

• stop forcing dev writeToDisk so Rsbuild keeps dev output in its memory filesystem
• disable classic web splitChunks/runtimeChunk in dev by default while preserving user rspack optimization overrides
• cache identical route transform results across inline/worker executors

Verification

• pnpm test:core
• pnpm build
• pnpm bench:smoke
• node scripts/bench-builds.mts --profile smoke --mode dev --iterations 1 --warmup 0 --format both --out .benchmark/results/dev-smoke
• pnpm prettier --check src/index.ts src/parallel-route-transforms.ts tests/index.test.ts tests/features.test.ts tests/parallel-route-transforms.test.ts tests/dev-runtime.integration.test.ts
• git diff --check

[pkg-pr-new]

Open in StackBlitz

pnpm add https://pkg.pr.new/rsbuild-plugin-react-router@e5dc8b6

commit: e5dc8b6

[github-actions]

Benchmark Results

Compared PR head e5dc8b6 against base 7bb55da.

Reading benchmark confidence

Raw deltas are always shown. The signal label only indicates whether the observed median delta is larger than a robust run-to-run noise band; it does not erase or replace the measurement.

The noise band is the larger of 2% or two combined robust standard deviations estimated from each side's relative median absolute deviation (rMAD). Fewer than three finite samples is reported as insufficient data. An inconclusive result should be rerun or investigated from the uploaded raw samples before drawing a performance conclusion.

Benchmark	Runs	Base total	Head total	Delta	Base rMAD	Head rMAD	Noise band	Signal
large-355-ssr-esm (build)	3	8.53s	8.55s	+0.3%	0.4%	0.2%	±2.0%	⚪ inconclusive
synthetic-1024-ssr-esm (build)	3	4.09s	4.30s	+5.2%	0.1%	0.2%	±2.0%	🔴 regression
synthetic-1024-ssr-esm-split (build)	3	5.58s	5.67s	+1.7%	0.1%	1.0%	±3.0%	⚪ inconclusive
synthetic-256-sourcemaps (build)	5	2.24s	2.19s	-2.3%	0.1%	0.8%	±2.3%	🟢 improvement
synthetic-256-ssr-esm (build)	5	2.09s	2.06s	-1.5%	0.9%	1.9%	±6.1%	⚪ inconclusive
synthetic-256-ssr-esm-split (build)	5	2.50s	2.46s	-1.5%	0.0%	0.3%	±2.0%	⚪ inconclusive
synthetic-48-ssr-esm (build)	5	1.37s	1.36s	-0.8%	1.1%	1.1%	±4.7%	⚪ inconclusive
large-355-ssr-esm (dev)	3	15.57s	14.99s	-3.7%	1.5%	0.3%	±4.5%	⚪ inconclusive
synthetic-1024-ssr-esm (dev)	3	4.74s	5.18s	+9.4%	0.4%	0.1%	±2.0%	🔴 regression
synthetic-1024-ssr-esm-split (dev)	3	4.83s	5.18s	+7.3%	0.3%	1.5%	±4.5%	🔴 regression
synthetic-256-sourcemaps (dev)	5	2.11s	2.14s	+1.6%	0.9%	0.3%	±2.7%	⚪ inconclusive
synthetic-256-ssr-esm (dev)	5	1.89s	2.02s	+7.2%	1.3%	0.9%	±4.6%	🔴 regression
synthetic-256-ssr-esm-split (dev)	5	1.83s	2.03s	+11.0%	0.6%	0.6%	±2.6%	🔴 regression
synthetic-48-ssr-esm (dev)	5	0.95s	0.90s	-5.7%	0.5%	0.7%	±2.5%	🟢 improvement
complex app (cold)	3	113.10s	114.14s	+0.9%	0.6%	0.4%	±2.0%	⚪ inconclusive
complex app (dev)	3	100.33s	99.12s	-1.2%	0.2%	0.4%	±2.0%	⚪ inconclusive
complex app (warm)	3	79.19s	82.25s	+3.9%	0.3%	0.8%	±2.7%	🔴 regression

Dev Rollup

Group	Fixtures	Base total	Head total	Delta	Base ready	Head ready	Ready delta	Base routes	Head routes	Route delta	Base update/HMR	Head update/HMR	Update delta	Speedup
All dev fixtures	7	31.91s	32.45s	+1.7%	19.60s	21.15s	+7.9%	3.98s	4.06s	+2.0%	2.92s	2.63s	-10.1%	0.98x
Large app	1	15.57s	14.99s	-3.7%	8.24s	8.48s	+3.0%	1.94s	2.00s	+2.6%	1.72s	1.55s	-9.9%	1.04x
Standard fixtures	6	16.34s	17.46s	+6.8%	11.36s	12.67s	+11.5%	2.03s	2.06s	+1.4%	1.21s	1.08s	-10.4%	0.94x

Production Build Benchmarks

Rendered 7 production build benchmarks.

Benchmark	Runs	Base total	Head total	Delta	Head mean	Head p95	Speedup	Head RSS p95
large-355-ssr-esm	3	8.53s	8.55s	+0.3%	8.53s	8.57s	1.00x	1456 MB
synthetic-1024-ssr-esm	3	4.09s	4.30s	+5.2%	4.34s	4.43s	0.95x	541 MB
synthetic-1024-ssr-esm-split	3	5.58s	5.67s	+1.7%	5.64s	5.73s	0.98x	650 MB
synthetic-256-sourcemaps	5	2.24s	2.19s	-2.3%	2.18s	2.20s	1.02x	377 MB
synthetic-256-ssr-esm	5	2.09s	2.06s	-1.5%	2.06s	2.11s	1.02x	363 MB
synthetic-256-ssr-esm-split	5	2.50s	2.46s	-1.5%	2.45s	2.47s	1.02x	368 MB
synthetic-48-ssr-esm	5	1.37s	1.36s	-0.8%	1.36s	1.38s	1.01x	304 MB

ci-small+ci-large Dev Fixture Summary

Rendered 7 dev benchmark fixtures from the ci-small+ci-large profile.

Benchmark	Runs	Base total	Head total	Delta	Base ready	Head ready	Base routes	Head routes	Base update/HMR	Head update/HMR	Update delta	Head mean	Head p95	Speedup	Head RSS p95
large-355-ssr-esm	3	15.57s	14.99s	-3.7%	8.24s	8.48s	1.94s	2.00s	1.72s	1.55s	-9.9%	14.98s	15.03s	1.04x	-
synthetic-1024-ssr-esm	3	4.74s	5.18s	+9.4%	3.27s	3.76s	0.60s	0.59s	0.35s	0.33s	-7.1%	5.18s	5.18s	0.91x	-
synthetic-1024-ssr-esm-split	3	4.83s	5.18s	+7.3%	3.35s	3.74s	0.59s	0.59s	0.35s	0.33s	-7.6%	5.18s	5.26s	0.93x	-
synthetic-256-sourcemaps	5	2.11s	2.14s	+1.6%	1.52s	1.59s	0.25s	0.26s	0.15s	0.13s	-16.1%	2.15s	2.18s	0.98x	-
synthetic-256-ssr-esm	5	1.89s	2.02s	+7.2%	1.29s	1.48s	0.23s	0.25s	0.15s	0.13s	-16.0%	2.03s	2.07s	0.93x	-
synthetic-256-ssr-esm-split	5	1.83s	2.03s	+11.0%	1.27s	1.48s	0.23s	0.25s	0.15s	0.13s	-16.4%	2.03s	2.09s	0.90x	-
synthetic-48-ssr-esm	5	0.95s	0.90s	-5.7%	0.67s	0.63s	0.12s	0.13s	0.05s	0.05s	-0.8%	0.90s	0.91s	1.06x	-

large-355-ssr-esm Plugin Operations

Environment	Operation	Count	Base total	Head total	Delta	Head wall	Head max	Reports
web	route:module	1071	1048.6ms	2890.6ms	+175.7%	2890.6ms	25.7ms	20
node	route:module	1071	600.7ms	971.0ms	+61.6%	971.0ms	8.8ms	42
web	route:client-entry	1071	272.1ms	253.4ms	-6.9%	253.4ms	5.6ms	6
node	manifest:transform	3	73.8ms	63.0ms	-14.6%	63.0ms	24.8ms	3
web	manifest:stage	6	12.1ms	8.6ms	-28.9%	8.6ms	1.9ms	6
web	manifest:transform	3	0.3ms	0.3ms	0.0%	0.3ms	0.1ms	3

synthetic-1024-ssr-esm Plugin Operations

Environment	Operation	Count	Base total	Head total	Delta	Head wall	Head max	Reports
web	route:module	3078	1219.0ms	2196.0ms	+80.1%	2196.0ms	14.2ms	27
node	route:module	3078	539.5ms	994.5ms	+84.3%	994.5ms	7.2ms	24
web	route:client-entry	3078	379.0ms	375.5ms	-0.9%	375.5ms	6.3ms	6
node	manifest:transform	3	127.4ms	130.1ms	+2.1%	130.1ms	45.0ms	3
node	module:client-only-stub	3	72.6ms	19.4ms	-73.3%	19.4ms	8.2ms	3
web	manifest:stage	6	40.9ms	35.7ms	-12.7%	35.7ms	6.9ms	6
web	manifest:transform	3	0.3ms	0.3ms	0.0%	0.3ms	0.1ms	3

synthetic-1024-ssr-esm-split Plugin Operations

Environment	Operation	Count	Base total	Head total	Delta	Head wall	Head max	Reports
web	route:module	3078	1271.5ms	2200.4ms	+73.1%	2200.4ms	34.5ms	26
node	route:module	3078	575.5ms	1061.5ms	+84.4%	1061.5ms	6.4ms	24
web	route:client-entry	3078	383.8ms	416.9ms	+8.6%	416.9ms	7.6ms	6
node	manifest:transform	3	129.5ms	125.2ms	-3.3%	125.2ms	45.5ms	3
node	module:client-only-stub	3	100.6ms	25.4ms	-74.8%	25.4ms	12.8ms	3
web	manifest:stage	6	38.5ms	27.7ms	-28.1%	27.7ms	6.7ms	6
web	manifest:transform	3	0.3ms	0.3ms	0.0%	0.3ms	0.1ms	3

synthetic-256-sourcemaps Plugin Operations

Environment	Operation	Count	Base total	Head total	Delta	Head wall	Head max	Reports
web	route:module	1290	718.9ms	1511.8ms	+110.3%	1511.8ms	33.7ms	20
node	route:module	1290	303.4ms	582.8ms	+92.1%	582.8ms	4.6ms	35
web	route:client-entry	1290	206.3ms	203.1ms	-1.6%	203.1ms	4.9ms	10
node	manifest:transform	5	76.7ms	77.0ms	+0.4%	77.0ms	19.4ms	5
node	module:client-only-stub	5	69.6ms	38.9ms	-44.1%	38.9ms	14.3ms	5
web	manifest:stage	11	14.3ms	10.5ms	-26.6%	10.5ms	1.3ms	11
web	manifest:transform	5	0.5ms	0.5ms	0.0%	0.5ms	0.1ms	5

synthetic-256-ssr-esm Plugin Operations

Environment	Operation	Count	Base total	Head total	Delta	Head wall	Head max	Reports
web	route:module	1291	712.3ms	1455.4ms	+104.3%	1455.4ms	27.7ms	21
node	route:module	1290	266.8ms	545.9ms	+104.6%	545.9ms	3.4ms	32
web	route:client-entry	1291	213.7ms	209.1ms	-2.2%	209.1ms	5.0ms	11
node	manifest:transform	5	96.7ms	67.7ms	-30.0%	67.7ms	17.3ms	5
node	module:client-only-stub	5	46.6ms	33.3ms	-28.5%	33.3ms	11.8ms	5
web	manifest:stage	11	14.7ms	13.7ms	-6.8%	13.7ms	4.0ms	11
web	manifest:transform	5	0.5ms	0.5ms	0.0%	0.5ms	0.1ms	5

synthetic-256-ssr-esm-split Plugin Operations

Environment	Operation	Count	Base total	Head total	Delta	Head wall	Head max	Reports
web	route:module	1292	679.1ms	1474.4ms	+117.1%	1474.4ms	21.0ms	22
node	route:module	1290	287.7ms	529.4ms	+84.0%	529.4ms	3.7ms	35
web	route:client-entry	1292	219.0ms	211.8ms	-3.3%	211.8ms	5.5ms	12
node	module:client-only-stub	5	81.1ms	41.2ms	-49.2%	41.2ms	16.3ms	5
node	manifest:transform	5	67.2ms	83.9ms	+24.9%	83.9ms	21.6ms	5
web	manifest:stage	12	14.6ms	14.2ms	-2.7%	14.2ms	3.9ms	12
web	manifest:transform	5	0.5ms	0.5ms	0.0%	0.5ms	0.1ms	5

synthetic-48-ssr-esm Plugin Operations

Environment	Operation	Count	Base total	Head total	Delta	Head wall	Head max	Reports
web	route:module	251	255.1ms	196.1ms	-23.1%	196.1ms	9.9ms	11
node	route:module	250	84.5ms	76.3ms	-9.7%	76.3ms	0.6ms	10
web	route:client-entry	251	62.3ms	53.7ms	-13.8%	53.7ms	3.4ms	11
node	module:client-only-stub	5	43.5ms	33.4ms	-23.2%	33.4ms	12.8ms	5
node	manifest:transform	5	25.8ms	28.7ms	+11.2%	28.7ms	6.6ms	5
web	manifest:stage	11	3.5ms	2.9ms	-17.1%	2.9ms	0.4ms	11
web	manifest:transform	5	0.5ms	0.5ms	0.0%	0.5ms	0.1ms	5

Synthetic Rsbuild App

Rendered 2 production build benchmarks.

Benchmark	Runs	Base total	Head total	Delta	Head mean	Head p95	Speedup	Head RSS p95
complex app	3	113.10s	114.14s	+0.9%	114.01s	-	0.99x	-
complex app	3	79.19s	82.25s	+3.9%	81.89s	-	0.96x	-

Rendered 1 dev benchmark fixture from the embedded complex app.

Benchmark	Runs	Base total	Head total	Delta	Base ready	Head ready	Base routes	Head routes	Base update/HMR	Head update/HMR	Update delta	Head mean	Head p95	Speedup	Head RSS p95
complex app	3	100.33s	99.12s	-1.2%	89.43s	89.21s	2.90s	3.12s	3.37s	2.43s	-27.9%	99.13s	-	1.01x	-

Profile: ci-small+ci-large; mode: dev; iterations: 5; warmup: 1.
The uploaded benchmark artifact includes diagnostics/summary.md and diagnostics/summary.json with runner metadata, per-run timing samples, CPU/RSS samples, and plugin timing hot spots.
Workflow run