Add inline value support for small values (≤8 bytes) #89271

lukesandberg · 2026-01-29T23:50:42Z

Implement Inline Value Storage in SST Files

This PR enhances the Static Sorted Table (SST) file format by implementing inline value storage for small values (≤8 bytes). Instead of storing these small values in separate value blocks, they are now stored directly in the key blocks, which:

Reduces indirection overhead (8 bytes per value)
Improves read performance by eliminating an extra lookup
Reduces the total size of SST files

The implementation:

Adds a new EntryValue::Inline variant for values ≤8 bytes
- for values <=8 bytes the 'small value' encoding is pure overhead (8 bytes to address <=8 bytes). This threshold was chosen to not regress key block sizes.
Introduces key block entry types 8-255 to encode inline values (supporting up to 247 bytes)
Updates the README to document the inline value format
Enhances ArcSlice with a new slice_from_subslice method for zero-copy access to inline values
Adds a Read implementation for ArcSlice<u8> to support streaming reads

lukesandberg · 2026-01-29T23:51:12Z

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codspeed-hq · 2026-01-30T00:13:58Z

Merging this PR will not alter performance

✅ 17 untouched benchmarks
⏩ 3 skipped benchmarks¹

_{Comparing inline_values_for_great_good (ade571c) with collision_tolerant_compaction (a0ba566)²}

3 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩
No successful run was found on collision_tolerant_compaction (c34eeaa) during the generation of this report, so 2a61196 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

nextjs-bot · 2026-01-30T00:14:49Z

Stats from current PR

✅ No significant changes detected

📊 All Metrics

📖 Metrics Glossary

Dev Server Metrics:

Listen = TCP port starts accepting connections
First Request = HTTP server returns successful response
Cold = Fresh build (no cache)
Warm = With cached build artifacts

Build Metrics:

Fresh = Clean build (no .next directory)
Cached = With existing .next directory

Change Thresholds:

Time: Changes < 50ms AND < 10%, OR < 2% are insignificant
Size: Changes < 1KB AND < 1% are insignificant
All other changes are flagged to catch regressions

⚡ Dev Server

Metric	Canary	PR	Change	Trend
Cold (Listen)	456ms	455ms	✓	▁▁█▁▁
Cold (Ready in log)	439ms	439ms	✓	██▆▆▇
Cold (First Request)	1.153s	1.191s	✓	▇▆▇▇▇
Warm (Listen)	456ms	456ms	✓	▁█▁▁█
Warm (Ready in log)	443ms	447ms	✓	▂▁▃▁▂
Warm (First Request)	341ms	345ms	✓	▅▁▅▁█

📦 Dev Server (Webpack) (Legacy)

📦 Dev Server (Webpack)

Metric	Canary	PR	Change	Trend
Cold (Listen)	458ms	456ms	✓	▁▁▁▁▁
Cold (Ready in log)	453ms	451ms	✓	▁▁▁▁▁
Cold (First Request)	1.803s	1.813s	✓	▁▁▁▁▁
Warm (Listen)	459ms	457ms	✓	▁▁▁▁▁
Warm (Ready in log)	451ms	451ms	✓	▁▁▁▁▁
Warm (First Request)	1.858s	1.805s	✓	▁▁▁▁▁

⚡ Production Builds

Metric	Canary	PR	Change	Trend
Fresh Build	3.985s	3.937s	✓	▂▁▁▁▁
Cached Build	3.847s	3.903s	✓	▁▁▁▁▁

📦 Production Builds (Webpack) (Legacy)

📦 Production Builds (Webpack)

Metric	Canary	PR	Change	Trend
Fresh Build	14.485s	14.495s	✓	▂▁▁▁▁
Cached Build	14.526s	14.626s	✓	▁▁▁▁▁
node_modules Size	463 MB	463 MB	✓	▁▁▁▁▁

📦 Bundle Sizes

Bundle Sizes

⚡ Turbopack

Client

Main Bundles: **434 kB** → **434 kB** ✅ -2 B

81 files with content-based hashes (individual files not comparable between builds)

Server

Middleware

	Canary	PR	Change
middleware-b..fest.js gzip	765 B	765 B	✓
Total	765 B	765 B	✓

Build Details

Build Manifests

	Canary	PR	Change
_buildManifest.js gzip	451 B	451 B	✓
Total	451 B	451 B	✓

📦 Webpack

Client

Main Bundles

	Canary	PR	Change
5528-HASH.js gzip	5.47 kB	N/A	-
6280-HASH.js gzip	54.4 kB	N/A	-
6335.HASH.js gzip	169 B	N/A	-
912-HASH.js gzip	4.53 kB	N/A	-
e8aec2e4-HASH.js gzip	62.5 kB	N/A	-
framework-HASH.js gzip	59.7 kB	59.7 kB	✓
main-app-HASH.js gzip	255 B	254 B	✓
main-HASH.js gzip	39 kB	39 kB	✓
webpack-HASH.js gzip	1.68 kB	1.68 kB	✓
262-HASH.js gzip	N/A	4.52 kB	-
2889.HASH.js gzip	N/A	169 B	-
5602-HASH.js gzip	N/A	5.48 kB	-
6948ada0-HASH.js gzip	N/A	62.5 kB	-
9544-HASH.js gzip	N/A	55.1 kB	-
Total	228 kB	228 kB	⚠️ +693 B

Polyfills

	Canary	PR	Change
polyfills-HASH.js gzip	39.4 kB	39.4 kB	✓
Total	39.4 kB	39.4 kB	✓

Pages

	Canary	PR	Change
_app-HASH.js gzip	194 B	194 B	✓
_error-HASH.js gzip	183 B	180 B	🟢 3 B (-2%)
css-HASH.js gzip	331 B	330 B	✓
dynamic-HASH.js gzip	1.81 kB	1.81 kB	✓
edge-ssr-HASH.js gzip	256 B	256 B	✓
head-HASH.js gzip	351 B	352 B	✓
hooks-HASH.js gzip	384 B	383 B	✓
image-HASH.js gzip	580 B	581 B	✓
index-HASH.js gzip	260 B	260 B	✓
link-HASH.js gzip	2.49 kB	2.49 kB	✓
routerDirect..HASH.js gzip	320 B	319 B	✓
script-HASH.js gzip	386 B	386 B	✓
withRouter-HASH.js gzip	315 B	315 B	✓
1afbb74e6ecf..834.css gzip	106 B	106 B	✓
Total	7.97 kB	7.97 kB	✅ -1 B

Server

Edge SSR

	Canary	PR	Change
edge-ssr.js gzip	126 kB	126 kB	✓
page.js gzip	247 kB	248 kB	✓
Total	374 kB	374 kB	⚠️ +311 B

Middleware

	Canary	PR	Change
middleware-b..fest.js gzip	616 B	614 B	✓
middleware-r..fest.js gzip	156 B	155 B	✓
middleware.js gzip	33.1 kB	33.2 kB	✓
edge-runtime..pack.js gzip	842 B	842 B	✓
Total	34.7 kB	34.8 kB	⚠️ +102 B

Build Details

Build Manifests

	Canary	PR	Change
_buildManifest.js gzip	732 B	736 B	✓
Total	732 B	736 B	⚠️ +4 B

Build Cache

	Canary	PR	Change
0.pack gzip	3.76 MB	3.77 MB	🔴 +7.52 kB (+0%)
index.pack gzip	101 kB	102 kB	✓
index.pack.old gzip	103 kB	103 kB	✓
Total	3.97 MB	3.98 MB	⚠️ +8.35 kB

🔄 Shared (bundler-independent)

Runtimes

	Canary	PR	Change
app-page-exp...dev.js gzip	311 kB	311 kB	✓
app-page-exp..prod.js gzip	166 kB	166 kB	✓
app-page-tur...dev.js gzip	311 kB	311 kB	✓
app-page-tur..prod.js gzip	166 kB	166 kB	✓
app-page-tur...dev.js gzip	307 kB	307 kB	✓
app-page-tur..prod.js gzip	164 kB	164 kB	✓
app-page.run...dev.js gzip	307 kB	307 kB	✓
app-page.run..prod.js gzip	164 kB	164 kB	✓
app-route-ex...dev.js gzip	70.2 kB	70.2 kB	✓
app-route-ex..prod.js gzip	48.8 kB	48.8 kB	✓
app-route-tu...dev.js gzip	70.2 kB	70.2 kB	✓
app-route-tu..prod.js gzip	48.8 kB	48.8 kB	✓
app-route-tu...dev.js gzip	69.8 kB	69.8 kB	✓
app-route-tu..prod.js gzip	48.6 kB	48.6 kB	✓
app-route.ru...dev.js gzip	69.8 kB	69.8 kB	✓
app-route.ru..prod.js gzip	48.6 kB	48.6 kB	✓
dist_client_...dev.js gzip	324 B	324 B	✓
dist_client_...dev.js gzip	326 B	326 B	✓
dist_client_...dev.js gzip	318 B	318 B	✓
dist_client_...dev.js gzip	317 B	317 B	✓
pages-api-tu...dev.js gzip	43.1 kB	43.1 kB	✓
pages-api-tu..prod.js gzip	32.8 kB	32.8 kB	✓
pages-api.ru...dev.js gzip	43.1 kB	43.1 kB	✓
pages-api.ru..prod.js gzip	32.8 kB	32.8 kB	✓
pages-turbo....dev.js gzip	52.4 kB	52.4 kB	✓
pages-turbo...prod.js gzip	39.3 kB	39.3 kB	✓
pages.runtim...dev.js gzip	52.4 kB	52.4 kB	✓
pages.runtim..prod.js gzip	39.3 kB	39.3 kB	✓
server.runti..prod.js gzip	62.5 kB	62.5 kB	✓
Total	2.77 MB	2.77 MB	✓

Store small values directly in the key block entry, eliminating the 8-byte indirection overhead (2-byte block index + 2-byte size + 4-byte position) for values that fit within that space. Key changes: - Add EntryValue::Inline variant for values ≤8 bytes - Add KEY_BLOCK_ENTRY_TYPE_INLINE_MIN (8) - types 8-255 encode inline sizes 0-247 - Return zero-copy ArcSlice for inline values via slice_from_subslice - Consolidate ArcSlice API: remove new_unchecked/full_arc, add slice_from_subslice

nextjs-bot · 2026-01-30T01:45:20Z

Failing test suites

Commit: ade571c | About building and testing Next.js

pnpm test-start-turbo test/e2e/app-dir/segment-cache/prefetch-runtime/prefetch-runtime.test.ts (turbopack) (job)

runtime prefetching > passed to a public cache > can completely prefetch a page that uses cookies and no uncached IO (DD)

Expand output

● runtime prefetching › passed to a public cache › can completely prefetch a page that uses cookies and no uncached IO

apiRequestContext.fetch: socket hang up
Call log:
  - → GET http://localhost:42601/passed-to-public-cache/cookies-only?_rsc=gtqjj
  -   user-agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) HeadlessChrome/130.0.6723.31 Safari/537.36
  -   accept: */*
  -   accept-encoding: gzip,deflate,br
  -   cookie: testCookie=initialValue
  -   next-test-fetch-priority: low
  -   referer: http://localhost:42601/
  -   next-router-prefetch: 1
  -   next-router-segment-prefetch: /!KGRlZmF1bHQp/passed-to-public-cache
  -   next-url: /
  -   rsc: 1
  -   sec-ch-ua: "Chromium";v="130", "HeadlessChrome";v="130", "Not?A_Brand";v="99"
  -   sec-ch-ua-mobile: ?0
  -   sec-ch-ua-platform: "Linux"

  225 |             // server; we pass the request to the server the immediately.
  226 |             result: (async () => {
> 227 |               const originalResponse = await page.request.fetch(request, {
      |                                                           ^
  228 |                 maxRedirects: 0,
  229 |               })
  230 |

  at fetch (lib/router-act.ts:227:59)
  at lib/router-act.ts:245:13
  at routeHandler (lib/router-act.ts:257:7)

● runtime prefetching › passed to a public cache › can completely prefetch a page that uses cookies and no uncached IO

apiRequestContext.fetch: socket hang up
Call log:
  - → GET http://localhost:42601/passed-to-public-cache/cookies-only?_rsc=o863q
  -   user-agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) HeadlessChrome/130.0.6723.31 Safari/537.36
  -   accept: */*
  -   accept-encoding: gzip,deflate,br
  -   cookie: testCookie=initialValue
  -   next-test-fetch-priority: low
  -   referer: http://localhost:42601/
  -   next-router-prefetch: 1
  -   next-router-segment-prefetch: /!KGRlZmF1bHQp
  -   next-url: /
  -   rsc: 1
  -   sec-ch-ua: "Chromium";v="130", "HeadlessChrome";v="130", "Not?A_Brand";v="99"
  -   sec-ch-ua-mobile: ?0
  -   sec-ch-ua-platform: "Linux"

  225 |             // server; we pass the request to the server the immediately.
  226 |             result: (async () => {
> 227 |               const originalResponse = await page.request.fetch(request, {
      |                                                           ^
  228 |                 maxRedirects: 0,
  229 |               })
  230 |

  at fetch (lib/router-act.ts:227:59)
  at lib/router-act.ts:245:13
  at routeHandler (lib/router-act.ts:257:7)

● runtime prefetching › passed to a public cache › can completely prefetch a page that uses cookies and no uncached IO

apiRequestContext.fetch: socket hang up
Call log:
  - → GET http://localhost:42601/passed-to-public-cache/cookies-only?_rsc=nn07o
  -   user-agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) HeadlessChrome/130.0.6723.31 Safari/537.36
  -   accept: */*
  -   accept-encoding: gzip,deflate,br
  -   cookie: testCookie=initialValue
  -   next-test-fetch-priority: low
  -   referer: http://localhost:42601/
  -   next-router-prefetch: 1
  -   next-router-segment-prefetch: /_index
  -   next-url: /
  -   rsc: 1
  -   sec-ch-ua: "Chromium";v="130", "HeadlessChrome";v="130", "Not?A_Brand";v="99"
  -   sec-ch-ua-mobile: ?0
  -   sec-ch-ua-platform: "Linux"

  225 |             // server; we pass the request to the server the immediately.
  226 |             result: (async () => {
> 227 |               const originalResponse = await page.request.fetch(request, {
      |                                                           ^
  228 |                 maxRedirects: 0,
  229 |               })
  230 |

  at fetch (lib/router-act.ts:227:59)
  at lib/router-act.ts:245:13
  at routeHandler (lib/router-act.ts:257:7)

● runtime prefetching › passed to a public cache › can completely prefetch a page that uses cookies and no uncached IO

apiRequestContext.fetch: socket hang up
Call log:
  - → GET http://localhost:42601/passed-to-public-cache/cookies-only?_rsc=nn07o
  -   user-agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) HeadlessChrome/130.0.6723.31 Safari/537.36
  -   accept: */*
  -   accept-encoding: gzip,deflate,br
  -   cookie: testCookie=initialValue
  -   next-test-fetch-priority: low
  -   referer: http://localhost:42601/
  -   next-router-prefetch: 1
  -   next-router-segment-prefetch: /_index
  -   next-url: /
  -   rsc: 1
  -   sec-ch-ua: "Chromium";v="130", "HeadlessChrome";v="130", "Not?A_Brand";v="99"
  -   sec-ch-ua-mobile: ?0
  -   sec-ch-ua-platform: "Linux"

  225 |             // server; we pass the request to the server the immediately.
  226 |             result: (async () => {
> 227 |               const originalResponse = await page.request.fetch(request, {
      |                                                           ^
  228 |                 maxRedirects: 0,
  229 |               })
  230 |

  at fetch (lib/router-act.ts:227:59)
  at lib/router-act.ts:245:13
  at routeHandler (lib/router-act.ts:257:7)

pnpm test packages/next/src/server/app-render/action-handler.test.ts (job)

Expand output

● Test suite failed to run

Jest encountered an unexpected token

Jest failed to parse a file. This happens e.g. when your code or its dependencies use non-standard JavaScript syntax, or when Jest is not configured to support such syntax.

Out of the box Jest supports Babel, which will be used to transform your files into valid JS based on your Babel configuration.

By default "node_modules" folder is ignored by transformers.

Here's what you can do:
 • If you are trying to use ECMAScript Modules, see https://jestjs.io/docs/ecmascript-modules for how to enable it.
 • If you are trying to use TypeScript, see https://jestjs.io/docs/getting-started#using-typescript
 • To have some of your "node_modules" files transformed, you can specify a custom "transformIgnorePatterns" in your config.
 • If you need a custom transformation specify a "transform" option in your config.
 • If you simply want to mock your non-JS modules (e.g. binary assets) you can stub them out with the "moduleNameMapper" config option.

You'll find more details and examples of these config options in the docs:
https://jestjs.io/docs/configuration
For information about custom transformations, see:
https://jestjs.io/docs/code-transformation

Details:

C:\actions-runner\_work\next.js\next.js\packages\next\src\server\app-render\action-handler.ts:1
({"Object.<anonymous>":function(module,exports,require,__dirname,__filename,jest){import { RSC_HEADER, RSC_CONTENT_TYPE_HEADER, NEXT_ROUTER_STATE_TREE_HEADER, ACTION_HEADER, NEXT_ACTION_NOT_FOUND_HEADER, NEXT_ROUTER_PREFETCH_HEADER, NEXT_ROUTER_SEGMENT_PREFETCH_HEADER, NEXT_URL, NEXT_ACTION_REVALIDATED_HEADER } from '../../client/components/app-router-headers';
                                                                                  ^^^^^^

SyntaxError: Cannot use import statement outside a module

  3 | describe('parseHostHeader', () => {
  4 |   it('should return correct host', () => {
> 5 |     expect(parseHostHeader({})).toBe(undefined)
    |                        ^
  6 |
  7 |     expect(
  8 |       parseHostHeader({

  at Runtime.createScriptFromCode (../node_modules/.pnpm/jest-runtime@29.7.0/node_modules/jest-runtime/build/index.js:1505:14)
  at Object.<anonymous> (../packages/next/src/server/app-render/action-handler.test.ts:5:24)

nextjs-bot added created-by: Turbopack team PRs by the Turbopack team. Turbopack Related to Turbopack with Next.js. labels Jan 29, 2026

lukesandberg mentioned this pull request Jan 29, 2026

Create a new compaction mechanism to ensure the TaskCache functions properly #89075

Draft

lukesandberg added 2 commits January 29, 2026 17:14

simplify signatures by just passing an ArcSlice down

ade571c

lukesandberg force-pushed the collision_tolerant_compaction branch from a0ba566 to c34eeaa Compare January 30, 2026 01:26

lukesandberg force-pushed the inline_values_for_great_good branch from a4b02d6 to ade571c Compare January 30, 2026 01:26

This was referenced Jan 30, 2026

[turbopack] Make compression in SST files disableable #89309

Draft

[turbopack] Add a simple tool to inspect serialized SST files and report on their contents #89310

Draft

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Add inline value support for small values (≤8 bytes) #89271

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