@samitouri / QOS-React / commits / 8e9a5fc6c1

[Fizz] Enable the progressiveChunkSize option (#33027)

Since the very beginning we have had the `progressiveChunkSize` option but we never actually took advantage of it because we didn't count the bytes that we emitted. This starts counting the bytes by taking a pass over the added chunks each time a segment completes. That allows us to outline a Suspense boundary to stream in late even if it is already loaded by the time that back-pressure flow and in a `prerender`. Meaning it gets inserted with script. The effect can be seen in the fixture where if you have large HTML content that can block initial paint (thanks to [`rel="expect"`](https://github.com/facebook/react/pull/33016) but also nested Suspense boundaries). Before this fix, the paint would be blocked until the large content loaded. This lets us paint the fallback first in the case that the raw bytes of the content takes a while to download. You can set it to `Infinity` to opt-out. E.g. if you want to ensure there's never any scripts. It's always set to `Infinity` in `renderToHTML` and the legacy `renderToString`. One downside is that if we might choose to outline a boundary, we need to let its fallback complete. We don't currently discount the size of the fallback but really just consider them additive even though in theory the fallback itself could also add significant size or even more than the content. It should maybe really be considered the delta but that would require us to track the size of the fallback separately which is tricky. One problem with the current heuristic is that we just consider the size of the boundary content itself down to the next boundary. If you have a lot of small boundaries adding up, it'll never kick in. I intend to address that in a follow up.

Sebastian Markbåge committed Apr 25, 2025 at 16:10 UTC 8e9a5fc6c1a6252ca1727ab8fe0d4ee13f2568ec
5 files changed +309 -16
fixtures/ssr/src/components/Chrome.js
+7 -1
@@ -4,6 +4,8 @@ import Theme, {ThemeToggleButton} from './Theme';
4
5 import './Chrome.css';
6
7 +import LargeContent from './LargeContent';
8 +
9 export default class Chrome extends Component {
10 state = {theme: 'light'};
11 render() {
@@ -25,7 +27,6 @@ export default class Chrome extends Component {
27 />
28 <Suspense fallback="Loading...">
29 <Theme.Provider value={this.state.theme}>
28 - {this.props.children}
30 <div>
31 <ThemeToggleButton
32 onChange={theme => {
@@ -35,9 +36,14 @@ export default class Chrome extends Component {
36 }}
37 />
38 </div>
39 + {this.props.children}
40 </Theme.Provider>
41 </Suspense>
42 <p>This should appear in the first paint.</p>
43 + <Suspense fallback="Loading...">
44 + <p>This content should not block paint.</p>
45 + <LargeContent />
46 + </Suspense>
47 <script
48 dangerouslySetInnerHTML={{
49 __html: `assetManifest = ${JSON.stringify(assets)};`,
fixtures/ssr/src/components/LargeContent.js new
+243
@@ -0,0 +1,243 @@
1 +import React, {Fragment} from 'react';
2 +
3 +export default function LargeContent() {
4 + return (
5 + <Fragment>
6 + <p>
7 + Lorem ipsum dolor sit amet, consectetur adipiscing elit. Mauris
8 + porttitor tortor ac lectus faucibus, eget eleifend elit hendrerit.
9 + Integer porttitor nisi in leo congue rutrum. Morbi sed ante posuere,
10 + aliquam lorem ac, imperdiet orci. Duis malesuada gravida pharetra. Cras
11 + facilisis arcu diam, id dictum lorem imperdiet a. Suspendisse aliquet
12 + tempus tortor et ultricies. Aliquam libero velit, posuere tempus ante
13 + sed, pellentesque tincidunt lorem. Nullam iaculis, eros a varius
14 + aliquet, tortor felis tempor metus, nec cursus felis eros aliquam nulla.
15 + Vivamus ut orci sed mauris congue lacinia. Cras eget blandit neque.
16 + Pellentesque a massa in turpis ullamcorper volutpat vel at massa. Sed
17 + ante est, auctor non diam non, vulputate ultrices metus. Maecenas dictum
18 + fermentum quam id aliquam. Donec porta risus vitae pretium posuere.
19 + Fusce facilisis eros in lacus tincidunt congue.
20 + </p>
21 + <p>
22 + Pellentesque habitant morbi tristique senectus et netus et malesuada
23 + fames ac turpis egestas. Phasellus dolor ante, iaculis vel nisl vitae,
24 + ornare ornare orci. Praesent sit amet lobortis sapien. Suspendisse
25 + pharetra posuere libero ut dapibus. Donec condimentum ante urna. Aliquam
26 + laoreet tincidunt lacus, sed interdum tortor dapibus elementum. Nam sed
27 + faucibus lorem. Suspendisse finibus, velit sed molestie finibus, risus
28 + purus mollis ante, sit amet aliquet sapien nulla ut nibh. In eget ligula
29 + metus. Duis in purus mattis, blandit magna nec, dictum nunc.
30 + </p>
31 + <p>
32 + Sed convallis magna id tortor blandit dictum. Suspendisse in porttitor
33 + neque. Integer quis metus consequat, rutrum est sit amet, finibus justo.
34 + In hac habitasse platea dictumst. Nullam sagittis, risus sed vehicula
35 + porta, sapien elit ultrices nibh, vel luctus odio tortor et ante. Sed
36 + porta enim in hendrerit tristique. Pellentesque id feugiat libero, sit
37 + amet tempor enim. Proin gravida nisl justo, vel ornare dolor bibendum
38 + ac. Mauris scelerisque mattis facilisis. Praesent sodales augue mollis
39 + orci vulputate aliquet. Mauris molestie luctus neque, sed congue elit
40 + congue ut. Cras quis tortor augue. In auctor nulla vel turpis dapibus
41 + egestas. Phasellus consequat rhoncus nisi sed dignissim. Quisque varius
42 + justo non ex lobortis finibus cursus nec justo. Nulla erat neque,
43 + commodo et sem convallis, tristique faucibus odio.
44 + </p>
45 + <p>
46 + Ut condimentum volutpat sem, id accumsan augue placerat vel. Donec ac
47 + efficitur turpis. Suspendisse pretium odio euismod sapien bibendum, sed
48 + tempus est condimentum. Etiam nisl magna, consequat at ullamcorper at,
49 + sollicitudin eu eros. In mattis ligula arcu. Sed eu consectetur turpis,
50 + id molestie ligula. Vestibulum et venenatis enim. Donec condimentum
51 + vitae nisi et placerat. Sed fringilla vehicula egestas. Proin
52 + consectetur, nibh non ornare scelerisque, diam lorem cursus lectus, ut
53 + mattis mauris purus id mi. Curabitur non ligula sit amet augue molestie
54 + vulputate. Donec maximus magna at volutpat aliquet. Pellentesque
55 + dignissim nulla eget odio eleifend tincidunt. Etiam diam lorem, ornare
56 + vel scelerisque vel, iaculis id risus. Donec aliquet aliquam felis, ac
57 + vehicula lacus suscipit vitae. Morbi eu ligula elit.
58 + </p>
59 + <p>
60 + Praesent pellentesque, libero ut faucibus tempor, purus elit consequat
61 + metus, in ornare nulla lectus at erat. Duis quis blandit turpis. Fusce
62 + at ligula rutrum metus molestie tempor sit amet eu justo. Maecenas
63 + tincidunt nisl nunc. Morbi ac metus tempor, pretium arcu vel, dapibus
64 + velit. Nulla convallis ligula at porta mollis. Duis magna ante, mollis
65 + eget nibh in, congue tempor dolor. Sed tincidunt sagittis arcu, in
66 + ultricies neque tempor non. Suspendisse eget nunc neque. Nulla sit amet
67 + odio volutpat, maximus purus id, dictum metus. Integer consequat, orci
68 + nec ullamcorper porta, mauris libero vestibulum ipsum, nec tempor tellus
69 + enim non nunc. Quisque nisl risus, dapibus sit amet purus nec, aliquam
70 + finibus metus. Nullam condimentum urna viverra finibus cursus. Proin et
71 + sollicitudin tellus, porta fermentum felis. Maecenas ac turpis sed dui
72 + condimentum interdum sed sed erat. Mauris ut dignissim erat.
73 + </p>
74 + <p>
75 + Proin varius porta dui, id fringilla elit lobortis eget. Integer at
76 + metus elementum, efficitur eros id, euismod est. Morbi vestibulum nibh
77 + ac leo luctus sagittis. Praesent rhoncus, risus sit amet mattis dictum,
78 + diam sapien tempor neque, vel dignissim nulla neque eget ex. Nam
79 + sollicitudin metus quis ullamcorper dapibus. Nam tristique euismod
80 + efficitur. Pellentesque rhoncus vel sem eget lacinia. Pellentesque
81 + volutpat velit ac dignissim luctus. Vivamus euismod tortor at ligula
82 + mattis porta. Vestibulum ante ipsum primis in faucibus orci luctus et
83 + ultrices posuere cubilia curae;
84 + </p>
85 + <p>
86 + Proin blandit vulputate efficitur. Pellentesque sit amet porta odio.
87 + Nunc pulvinar varius rhoncus. Mauris fermentum leo a imperdiet pretium.
88 + Mauris scelerisque justo vel ante egestas, eget tempus neque malesuada.
89 + Sed dictum ex vel justo dignissim, aliquam commodo diam rutrum. Integer
90 + dignissim est ullamcorper augue laoreet consectetur id at diam. Vivamus
91 + molestie blandit urna, eget pulvinar augue dictum vestibulum. Duis
92 + maximus bibendum mauris, ut ultricies elit rhoncus eu. Praesent gravida
93 + placerat mauris. Praesent tempor ipsum at nibh rhoncus sagittis. Duis
94 + non sem turpis. Quisque et metus leo. Sed eu purus lorem. Pellentesque
95 + dictum metus sed leo viverra interdum. Maecenas vel tincidunt mi.
96 + </p>
97 + <p>
98 + Praesent consequat dapibus pellentesque. Fusce at enim id mauris laoreet
99 + commodo. Nullam ut mauris euismod, rhoncus tellus vel, facilisis diam.
100 + Aenean porta faucibus augue, a iaculis massa iaculis in. Praesent vel
101 + metus purus. Etiam quis augue eget orci lobortis eleifend ac ut lorem.
102 + Aenean non orci quis nisi molestie maximus. Mauris interdum, eros et
103 + aliquam aliquam, lectus diam pharetra velit, in condimentum odio eros
104 + non quam. Praesent bibendum pretium turpis vitae tristique. Mauris
105 + convallis, massa ut fermentum fermentum, libero orci tempus ipsum,
106 + malesuada ultrices metus sapien placerat lectus. Ut fringilla arcu nec
107 + lorem ultrices mattis. Etiam id tortor feugiat magna gravida gravida.
108 + Morbi aliquam, mi ac pellentesque mattis, erat ex venenatis erat, a
109 + vestibulum eros turpis quis metus. Pellentesque tempus justo in ligula
110 + ultricies porta. Phasellus congue felis sit amet dolor tristique
111 + finibus. Nunc eget eros non est ultricies vestibulum.
112 + </p>
113 + <p>
114 + Donec efficitur ligula quis odio tincidunt tristique. Duis urna dolor,
115 + hendrerit quis enim at, accumsan auctor turpis. Vivamus ante lorem,
116 + maximus vitae suscipit ut, congue eget velit. Maecenas sed ligula erat.
117 + Aliquam mollis purus at nisi porta suscipit in ut magna. Vivamus a
118 + turpis nec tellus egestas suscipit nec ornare nisi. Donec vestibulum
119 + libero quis ex suscipit, sit amet luctus leo gravida.
120 + </p>
121 + <p>
122 + Praesent pharetra dolor elit, sed volutpat lorem rhoncus non. Etiam a
123 + neque ut velit dignissim sodales. Vestibulum neque risus, condimentum
124 + nec consectetur vitae, ultricies ut sapien. Integer iaculis at urna sit
125 + amet malesuada. Integer tincidunt, felis ac vulputate semper, velit leo
126 + facilisis lorem, quis aliquet leo dui id lorem. Morbi non quam quis nisl
127 + sagittis consequat nec vitae libero. Nunc molestie pretium libero, eu
128 + eleifend nibh feugiat sed. Ut in bibendum diam, sit amet vehicula risus.
129 + Nam ornare ac nisi ac euismod. Nullam id egestas nulla. Etiam porta
130 + commodo ante sit amet pellentesque. Suspendisse eleifend purus in urna
131 + euismod auctor non vel nisi. Suspendisse rutrum est nunc, sit amet
132 + lacinia lacus dictum eget. Pellentesque habitant morbi tristique
133 + senectus et netus et malesuada fames ac turpis egestas. Morbi a blandit
134 + diam.
135 + </p>
136 + <p>
137 + Donec eget efficitur sapien. Suspendisse diam lacus, varius eu interdum
138 + et, congue ac justo. Proin ipsum odio, suscipit elementum mauris sed,
139 + porttitor congue est. Cras dapibus dictum ante, vitae gravida elit
140 + venenatis sed. Sed massa sem, posuere ut enim sit amet, vestibulum
141 + condimentum nibh. Pellentesque pulvinar sodales lacinia. Proin id
142 + pretium sapien, non convallis nulla. In mollis tincidunt sem et
143 + porttitor.
144 + </p>
145 + <p>
146 + Integer at sollicitudin sem. Suspendisse sed semper orci. Nulla at nibh
147 + nec risus suscipit posuere egestas vitae enim. Nullam mauris justo,
148 + mattis vel laoreet non, finibus nec nisl. Cras iaculis ultrices nibh,
149 + non commodo eros aliquam non. Sed vitae mollis dui, at maximus metus. Ut
150 + vestibulum, enim ut lobortis vulputate, lorem urna congue elit, non
151 + dictum odio lorem eget velit. Morbi eleifend id ligula vitae vulputate.
152 + Suspendisse ac laoreet justo. Proin eu mattis diam.
153 + </p>
154 + <p>
155 + Nunc in ex quis enim ullamcorper scelerisque eget ac eros. Class aptent
156 + taciti sociosqu ad litora torquent per conubia nostra, per inceptos
157 + himenaeos. Aliquam turpis dui, egestas a rhoncus non, fermentum in
158 + tellus. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices
159 + posuere cubilia curae; Aenean non risus arcu. Nam ultricies lacinia
160 + volutpat. Class aptent taciti sociosqu ad litora torquent per conubia
161 + nostra, per inceptos himenaeos. Lorem ipsum dolor sit amet, consectetur
162 + adipiscing elit.
163 + </p>
164 + <p>
165 + Aliquam a felis leo. Proin lorem ipsum, congue eu cursus in, rhoncus ut
166 + libero. Vestibulum sit amet consequat nunc. Ut eleifend lobortis lacus,
167 + vel molestie metus viverra eget. Nullam suscipit eu magna scelerisque
168 + suscipit. Donec dictum in diam nec lacinia. Mauris pellentesque ex ut
169 + purus facilisis, eget placerat turpis semper. Sed dapibus lorem ante, et
170 + malesuada dui eleifend ac. Sed diam felis, semper ac nulla vel, posuere
171 + ultricies ante.
172 + </p>
173 + <p>
174 + Nunc elementum odio sapien, sit amet vulputate lorem varius at. Fusce
175 + non sapien vitae lorem aliquam pretium sit amet congue dolor. Nunc quis
176 + tortor luctus, pretium ex a, tincidunt urna. Aliquam fermentum massa a
177 + erat pharetra varius. Curabitur at auctor dui. Sed posuere pellentesque
178 + massa, vel bibendum urna dictum non. Fusce eget rhoncus urna. Maecenas
179 + sed lectus tellus. Pellentesque convallis dapibus nisl vitae venenatis.
180 + Quisque ornare a dolor ac pharetra. Nam cursus, mi a lacinia accumsan,
181 + felis erat fringilla magna, ac mattis nunc ante a orci.
182 + </p>
183 + <p>
184 + Nunc vel tortor euismod, commodo tortor non, aliquam nisi. Maecenas
185 + tempus mollis velit non suscipit. Mauris sit amet dolor sed ex fringilla
186 + varius. Suspendisse vel cursus risus. Vivamus pharetra massa nec dolor
187 + aliquam feugiat. Fusce finibus enim commodo, scelerisque ante eu,
188 + laoreet ex. Curabitur placerat magna quis imperdiet lacinia. Etiam
189 + lectus mauris, porttitor ac lacinia sed, posuere eget lacus. Mauris
190 + vulputate mattis imperdiet. Nunc id aliquet libero, vitae hendrerit
191 + purus. Praesent vestibulum urna ac egestas tempor. In molestie, nunc sit
192 + amet sagittis dapibus, ligula enim fermentum mi, lacinia molestie eros
193 + dui in tortor. Mauris fermentum pulvinar faucibus. Curabitur laoreet
194 + eleifend purus, non tincidunt tortor gravida nec. Nam eu lectus congue,
195 + commodo libero et, porttitor est. Nullam tincidunt, nisi eu congue
196 + congue, magna justo commodo massa, nec efficitur dui lectus non sem.
197 + </p>
198 + <p>
199 + Nullam vehicula, ipsum quis lacinia tristique, elit nulla dignissim
200 + augue, at pulvinar metus justo ac magna. Nullam nec nunc ac sapien
201 + mollis cursus eu ac enim. Pellentesque a pharetra erat. Ut tempor magna
202 + nisi, accumsan blandit lectus volutpat nec. Vivamus vel lorem nec eros
203 + blandit dictum eget ac diam. Nulla nec turpis dolor. Morbi eu euismod
204 + libero. Nam ut tortor at arcu porta tincidunt. In gravida ligula
205 + fringilla ornare imperdiet. Nulla scelerisque ante erat, efficitur
206 + dictum metus ullamcorper vel. Nam ac purus metus. Maecenas eget tempus
207 + nulla. Ut magna lorem, efficitur ut ex a, semper aliquam magna. Praesent
208 + lobortis, velit ac posuere mattis, justo est accumsan turpis, id
209 + sagittis felis mi in lacus.
210 + </p>
211 + <p>
212 + Aenean est mi, semper nec sem at, malesuada consectetur nunc. Aenean
213 + consequat sem quis sem consequat, non aliquam est placerat. Cras
214 + malesuada magna neque, et pellentesque nibh consequat at. Sed interdum
215 + velit et ex interdum, vel lobortis ante vestibulum. Nam placerat lectus
216 + eu commodo efficitur. Pellentesque in nunc ac massa porttitor eleifend
217 + ut efficitur sem. Aenean at magna auctor, posuere augue in, ultrices
218 + arcu. Praesent dignissim augue ex, malesuada maximus metus interdum a.
219 + Proin nec odio in nulla vestibulum.
220 + </p>
221 + <p>
222 + Aenean est mi, semper nec sem at, malesuada consectetur nunc. Aenean
223 + consequat sem quis sem consequat, non aliquam est placerat. Cras
224 + malesuada magna neque, et pellentesque nibh consequat at. Sed interdum
225 + velit et ex interdum, vel lobortis ante vestibulum. Nam placerat lectus
226 + eu commodo efficitur. Pellentesque in nunc ac massa porttitor eleifend
227 + ut efficitur sem. Aenean at magna auctor, posuere augue in, ultrices
228 + arcu. Praesent dignissim augue ex, malesuada maximus metus interdum a.
229 + Proin nec odio in nulla vestibulum.
230 + </p>
231 + <p>
232 + Aenean est mi, semper nec sem at, malesuada consectetur nunc. Aenean
233 + consequat sem quis sem consequat, non aliquam est placerat. Cras
234 + malesuada magna neque, et pellentesque nibh consequat at. Sed interdum
235 + velit et ex interdum, vel lobortis ante vestibulum. Nam placerat lectus
236 + eu commodo efficitur. Pellentesque in nunc ac massa porttitor eleifend
237 + ut efficitur sem. Aenean at magna auctor, posuere augue in, ultrices
238 + arcu. Praesent dignissim augue ex, malesuada maximus metus interdum a.
239 + Proin nec odio in nulla vestibulum.
240 + </p>
241 + </Fragment>
242 + );
243 +}
packages/react-noop-renderer/src/ReactNoopServer.js
+2
@@ -98,6 +98,8 @@ const ReactNoopServer = ReactFizzServer({
98 closeWithError(destination: Destination, error: mixed): void {},
99 flushBuffered(destination: Destination): void {},
100
101 + byteLengthOfChunk: null,
102 +
103 getChildFormatContext(): null {
104 return null;
105 },
packages/react-server/src/ReactFizzServer.js
+54 -12
@@ -50,6 +50,7 @@ import {
50 flushBuffered,
51 close,
52 closeWithError,
53 + byteLengthOfChunk,
54 } from './ReactServerStreamConfig';
55 import {
56 writeCompletedRoot,
@@ -348,6 +349,7 @@ export opaque type Request = {
349 pendingRootTasks: number, // when this reaches zero, we've finished at least the root boundary.
350 completedRootSegment: null | Segment, // Completed but not yet flushed root segments.
351 completedPreambleSegments: null | Array<Array<Segment>>, // contains the ready-to-flush segments that make up the preamble
352 + byteSize: number, // counts the number of bytes accumulated in the shell
353 abortableTasks: Set<Task>,
354 pingedTasks: Array<Task>, // High priority tasks that should be worked on first.
355 // Queues to flush in order of priority
@@ -398,6 +400,13 @@ type Preamble = PreambleState;
400 // 500 * 1024 / 8 * .8 * 0.5 / 2
401 const DEFAULT_PROGRESSIVE_CHUNK_SIZE = 12800;
402
403 +function isEligibleForOutlining(
404 + request: Request,
405 + boundary: SuspenseBoundary,
406 +): boolean {
407 + return boundary.byteSize > request.progressiveChunkSize;
408 +}
409 +
410 function defaultErrorHandler(error: mixed) {
411 if (
412 typeof error === 'object' &&
@@ -447,6 +456,7 @@ function RequestInstance(
456 this.pendingRootTasks = 0;
457 this.completedRootSegment = null;
458 this.completedPreambleSegments = null;
459 + this.byteSize = 0;
460 this.abortableTasks = abortSet;
461 this.pingedTasks = pingedTasks;
462 this.clientRenderedBoundaries = ([]: Array<SuspenseBoundary>);
@@ -1235,6 +1245,7 @@ function renderSuspenseBoundary(
1245 boundarySegment.textEmbedded,
1246 );
1247 boundarySegment.status = COMPLETED;
1248 + finishedSegment(request, parentBoundary, boundarySegment);
1249 } catch (thrownValue: mixed) {
1250 if (request.status === ABORTING) {
1251 boundarySegment.status = ABORTED;
@@ -1301,20 +1312,24 @@ function renderSuspenseBoundary(
1312 contentRootSegment.textEmbedded,
1313 );
1314 contentRootSegment.status = COMPLETED;
1315 + finishedSegment(request, newBoundary, contentRootSegment);
1316 queueCompletedSegment(newBoundary, contentRootSegment);
1317 if (newBoundary.pendingTasks === 0 && newBoundary.status === PENDING) {
1318 // This must have been the last segment we were waiting on. This boundary is now complete.
1307 - // Therefore we won't need the fallback. We early return so that we don't have to create
1308 - // the fallback.
1319 newBoundary.status = COMPLETED;
1310 - if (request.pendingRootTasks === 0 && task.blockedPreamble) {
1311 - // The root is complete and this boundary may contribute part of the preamble.
1312 - // We eagerly attempt to prepare the preamble here because we expect most requests
1313 - // to have few boundaries which contribute preambles and it allow us to do this
1314 - // preparation work during the work phase rather than the when flushing.
1315 - preparePreamble(request);
1320 + // Therefore we won't need the fallback. We early return so that we don't have to create
1321 + // the fallback. However, if this boundary ended up big enough to be eligible for outlining
1322 + // we can't do that because we might still need the fallback if we outline it.
1323 + if (!isEligibleForOutlining(request, newBoundary)) {
1324 + if (request.pendingRootTasks === 0 && task.blockedPreamble) {
1325 + // The root is complete and this boundary may contribute part of the preamble.
1326 + // We eagerly attempt to prepare the preamble here because we expect most requests
1327 + // to have few boundaries which contribute preambles and it allow us to do this
1328 + // preparation work during the work phase rather than the when flushing.
1329 + preparePreamble(request);
1330 + }
1331 + return;
1332 }
1317 - return;
1333 }
1334 } catch (thrownValue: mixed) {
1335 newBoundary.status = CLIENT_RENDERED;
@@ -2451,6 +2466,7 @@ function resumeNode(
2466 renderTask.blockedSegment = resumedSegment;
2467 renderNode(request, task, node, childIndex);
2468 resumedSegment.status = COMPLETED;
2469 + finishedSegment(request, blockedBoundary, resumedSegment);
2470 if (blockedBoundary === null) {
2471 request.completedRootSegment = resumedSegment;
2472 } else {
@@ -4272,6 +4288,27 @@ function queueCompletedSegment(
4288 }
4289 }
4290
4291 +function finishedSegment(
4292 + request: Request,
4293 + boundary: Root | SuspenseBoundary,
4294 + segment: Segment,
4295 +) {
4296 + if (byteLengthOfChunk !== null) {
4297 + // Count the bytes of all the chunks of this segment.
4298 + const chunks = segment.chunks;
4299 + let segmentByteSize = 0;
4300 + for (let i = 0; i < chunks.length; i++) {
4301 + segmentByteSize += byteLengthOfChunk(chunks[i]);
4302 + }
4303 + // Accumulate on the parent boundary to power heuristics.
4304 + if (boundary === null) {
4305 + request.byteSize += segmentByteSize;
4306 + } else {
4307 + boundary.byteSize += segmentByteSize;
4308 + }
4309 + }
4310 +}
4311 +
4312 function finishedTask(
4313 request: Request,
4314 boundary: Root | SuspenseBoundary,
@@ -4318,9 +4355,13 @@ function finishedTask(
4355 // This needs to happen after we read the parentFlushed flags because aborting can finish
4356 // work which can trigger user code, which can start flushing, which can change those flags.
4357 // If the boundary was POSTPONED, we still need to finish the fallback first.
4358 + // If the boundary is eligible to be outlined during flushing we can't cancel the fallback
4359 + // since we might need it when it's being outlined.
4360 if (boundary.status === COMPLETED) {
4322 - boundary.fallbackAbortableTasks.forEach(abortTaskSoft, request);
4323 - boundary.fallbackAbortableTasks.clear();
4361 + if (!isEligibleForOutlining(request, boundary)) {
4362 + boundary.fallbackAbortableTasks.forEach(abortTaskSoft, request);
4363 + boundary.fallbackAbortableTasks.clear();
4364 + }
4365
4366 if (
4367 request.pendingRootTasks === 0 &&
@@ -4418,6 +4459,7 @@ function retryRenderTask(
4459
4460 task.abortSet.delete(task);
4461 segment.status = COMPLETED;
4462 + finishedSegment(request, task.blockedBoundary, segment);
4463 finishedTask(request, task.blockedBoundary, segment);
4464 } catch (thrownValue: mixed) {
4465 resetHooksState();
@@ -4929,7 +4971,7 @@ function flushSegment(
4971 flushSubtree(request, destination, segment, hoistableState);
4972
4973 return writeEndPendingSuspenseBoundary(destination, request.renderState);
4932 - } else if (boundary.byteSize > request.progressiveChunkSize) {
4974 + } else if (isEligibleForOutlining(request, boundary)) {
4975 // This boundary is large and will be emitted separately so that we can progressively show
4976 // other content. We add it to the queue during the flush because we have to ensure that
4977 // the parent flushes first so that there's something to inject it into.
packages/react-server/src/ReactServerStreamConfigFB.js
+3 -3
@@ -60,9 +60,9 @@ export function typedArrayToBinaryChunk(
60 throw new Error('Not implemented.');
61 }
62
63 -export function byteLengthOfChunk(chunk: Chunk | PrecomputedChunk): number {
64 - throw new Error('Not implemented.');
65 -}
63 +export const byteLengthOfChunk:
64 + | null
65 + | ((chunk: Chunk | PrecomputedChunk) => number) = null;
66
67 export function byteLengthOfBinaryChunk(chunk: BinaryChunk): number {
68 throw new Error('Not implemented.');