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bootstrap: lazy load non-essential modules #45659

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merged 1 commit into from Dec 9, 2022

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joyeecheung
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benchmark: make benchmarks runnable in older versions of Node.js

In addition make it runnable with --no-browser-globals

bootstrap: lazy load non-essential modules

It turns out that even with startup snapshots, there is a non-trivial
overhead for loading internal modules. This patch makes the loading
of the non-essential modules lazy again.

Caveat: we have to make some of the globals lazily-loaded too,
so the WPT runner is updated to test what the state of the global
scope is after the globals are accessed (and replaced with the
loaded value).

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Review requested:

  • @nodejs/modules
  • @nodejs/net
  • @nodejs/startup

@nodejs-github-bot nodejs-github-bot added lib / src Issues and PRs related to general changes in the lib or src directory. needs-ci PRs that need a full CI run. labels Nov 28, 2022
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joyeecheung commented Nov 28, 2022

Benchmark CI: https://ci.nodejs.org/view/Node.js%20benchmark/job/benchmark-node-micro-benchmarks/1241/

Results
                                                                                  confidence improvement accuracy (*)   (**)  (***)
misc/startup.js mode='process' script='benchmark/fixtures/require-builtins' dur=1        ***     -4.80 %       ±2.32% ±3.10% ±4.05%
misc/startup.js mode='process' script='benchmark/fixtures/require-cachable' dur=1        ***     -9.93 %       ±2.27% ±3.01% ±3.93%
misc/startup.js mode='process' script='test/fixtures/semicolon' dur=1                    ***     16.66 %       ±1.78% ±2.37% ±3.09%
misc/startup.js mode='worker' script='benchmark/fixtures/require-builtins' dur=1         ***     11.31 %       ±4.03% ±5.38% ±7.04%
misc/startup.js mode='worker' script='benchmark/fixtures/require-cachable' dur=1         ***      6.71 %       ±2.01% ±2.68% ±3.49%
misc/startup.js mode='worker' script='test/fixtures/semicolon' dur=1                     ***     36.80 %       ±2.69% ±3.59% ±4.69%

Be aware that when doing many comparisons the risk of a false-positive
result increases. In this case, there are 6 comparisons, you can thus
expect the following amount of false-positive results:
  0.30 false positives, when considering a   5% risk acceptance (*, **, ***),
  0.06 false positives, when considering a   1% risk acceptance (**, ***),
  0.01 false positives, when considering a 0.1% risk acceptance (***)


const {
newReadableStreamFromStreamBase,
} = require('internal/webstreams/adapters');
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The internal require() is actually just one map load (to see if the module is already loaded) + one property load (state check for circular dependencies) for modules that are already loaded, so I think it's fine to just inline these as they are followed by more expensive operations that will shadow the overhead of require()

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bnb commented Nov 28, 2022

this is awesome, amazing work @joyeecheung

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joyeecheung commented Nov 28, 2022

From the CI:

I think it's okay/predictable for the require-builtins and require-cachable benchmarks of the main process to regress a bit in favor of semicolon and the worker benchmarks. Most applications really only need a subset of the builtins, instead of all of them, and the modules removed here IMO either only work for a specific type of application (but not others), or there are multiple alternatives of them so it makes more sense to only pay the cost of one of them (when the user actually need them) instead of eagerly loading all the alternatives and paying for the extra cost.

17:49:10                                                                                   confidence improvement accuracy (*)   (**)  (***)
17:49:11 misc/startup.js mode='process' script='benchmark/fixtures/require-builtins' dur=1        ***     -4.80 %       ±2.32% ±3.10% ±4.05%
17:49:11 misc/startup.js mode='process' script='benchmark/fixtures/require-cachable' dur=1        ***     -9.93 %       ±2.27% ±3.01% ±3.93%
17:49:11 misc/startup.js mode='process' script='test/fixtures/semicolon' dur=1                    ***     16.66 %       ±1.78% ±2.37% ±3.09%
17:49:11 misc/startup.js mode='worker' script='benchmark/fixtures/require-builtins' dur=1         ***     11.31 %       ±4.03% ±5.38% ±7.04%
17:49:11 misc/startup.js mode='worker' script='benchmark/fixtures/require-cachable' dur=1         ***      6.71 %       ±2.01% ±2.68% ±3.49%
17:49:11 misc/startup.js mode='worker' script='test/fixtures/semicolon' dur=1                     ***     36.80 %       ±2.69% ±3.59% ±4.69%

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lgtm

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fantastic work. lgtm!

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anonrig commented Nov 29, 2022

cc @nodejs/performance

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Amazing the number of reduced modules bootstrapped. Thanks for this great work!

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Can you please summarize the overall benefit of this change? I assume it produces a faster startup (?) and how much faster does it get?

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aduh95 commented Nov 29, 2022

I assume it produces a faster startup (?) and how much faster does it get?

@GeoffreyBooth did you see #45659 (comment)?

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anonrig commented Nov 29, 2022

@joyeecheung Can you fix the js lint errors?

/home/runner/work/node/node/lib/internal/util.js
[10](https://github.com/nodejs/node/actions/runs/3575782975/jobs/6012760242#step:5:11)
Error:   508:14  error  Multiple spaces found before '='  no-multi-spaces
[11](https://github.com/nodejs/node/actions/runs/3575782975/jobs/6012760242#step:5:12)

[12](https://github.com/nodejs/node/actions/runs/3575782975/jobs/6012760242#step:5:13)
✖ 1 problem (1 error, 0 warnings)
[13](https://github.com/nodejs/node/actions/runs/3575782975/jobs/6012760242#step:5:14)
  1 error and 0 warnings potentially fixable with the `--fix` option.

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@GeoffreyBooth did you see #45659 (comment)?

Yes, but I don’t know how to interpret that. Is the semicolon benchmark a proxy for “start up and do nothing”? So base startup is 17% faster?

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anonrig commented Nov 29, 2022

@GeoffreyBooth did you see #45659 (comment)?

Yes, but I don’t know how to interpret that. Is the semicolon benchmark a proxy for “start up and do nothing”? So base startup is 17% faster?

@GeoffreyBooth Startup benchmark only benchmarks the startup time of a Node.js application. Loading a semicolon is a way of not calling any of the node applications, and benchmark the load time of all essential packages in Node.js (which directly effects the load time)

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Startup benchmark only benchmarks the startup time of a Node.js application. Loading a semicolon is a way of not calling any of the node applications, and benchmark the load time of all essential packages in Node.js (which directly effects the load time)

Okay, so is this a benchmark of how long Node itself takes to startup, when loading an application that does nothing? So therefore it’s fair to say that for the “noop app” case, this PR makes Node start up 17% faster?

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aduh95 commented Nov 29, 2022

So therefore it’s fair to say that for the “noop app” case, this PR makes Node start up 17% faster?

The benchmark is 99.9% confident that this PR improves the performance from 16.66 % - 3.09% up to 16.66 % + 3.09%. 17% is in this range, but it can be any other value in this range. Also, the benchmark is run on a specific machine, on a specific platform, so if you run it again on a different machine you are very likely to get a different figure. The prudent takeaway is "this PR makes Node.js start up faster", trying to be more specific is more likely to get you away from the truth than closer to it.

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Huzzah 🙌

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trying to be more specific is more likely to get you away from the truth than closer to it.

I think we should have some language that’s friendly enough that we can put it in the release notes. Making the runtime start 17-ish percent faster is a headline; so if that’s too imprecise, let’s come up with an alternative summary that’s still correct but not pedantic. @joyeecheung is it possible to pull the “semicolon” benchmark numbers for all the machines/platforms we test on? So that we can phrase a release note like “The node binary now starts up X% to Y% faster when loading an empty application, as measured on X CI machines covering X platforms.”

@GeoffreyBooth GeoffreyBooth added notable-change PRs with changes that should be highlighted in changelogs. performance Issues and PRs related to the performance of Node.js. and removed needs-ci PRs that need a full CI run. labels Nov 30, 2022
@aduh95 aduh95 added the needs-ci PRs that need a full CI run. label Nov 30, 2022
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joyeecheung commented Nov 30, 2022

“The node binary now starts up X% to Y% faster when loading an empty application, as measured on X CI machines covering X platforms.”

That's not how I would frame this PR, because this is only fixing a regression caused by being too careless about loading non-essential modules before, the startup is still slower compared to previous release lines. Part of the regression can be attributed to the "bloating" of the core - many of the modules loaded here were only added in recent releases, on main out/Release/node -p "process.moduleLoadList.join('\n')" | wc -l is 186, while it was ~136 for v16, ~88 for v14, this PR takes it back to 97. Another suspect can be the use of primordials, it could slow down the creation of vm contexts even with the help of the snapshots (-90% without snapshot, -30% with snapshot, from #44252 (comment)) . Even node --version, which involves no JS execution, has been much slower than before, which I am still looking into.

@GeoffreyBooth GeoffreyBooth mentioned this pull request Dec 20, 2022
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@joyeecheung this caused merge conflicts when landing in v18.x-staging. Do you mind creating a backport PR?

@danielleadams danielleadams added the backport-requested-v18.x PRs awaiting manual backport to the v18.x-staging branch. label Dec 30, 2022
danielleadams pushed a commit that referenced this pull request Dec 30, 2022
The internal `require()` is actually just one map load (to see if the
module is already loaded) + one property load (state check for circular
dependencies) for modules that are already loaded.

Refs: #45659 (comment)
PR-URL: #45809
Reviewed-By: Daeyeon Jeong <daeyeon.dev@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Minwoo Jung <nodecorelab@gmail.com>
danielleadams pushed a commit that referenced this pull request Dec 30, 2022
The internal `require()` is actually just one map load (to see if the
module is already loaded) + one property load (state check for circular
dependencies) for modules that are already loaded.

Refs: #45659 (comment)
PR-URL: #45809
Reviewed-By: Daeyeon Jeong <daeyeon.dev@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Minwoo Jung <nodecorelab@gmail.com>
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@danielleadams I think this probably needs more of a rewrite for v18.x instead of a simple backport. Will do it after the new years holidays

danielleadams pushed a commit that referenced this pull request Jan 3, 2023
The internal `require()` is actually just one map load (to see if the
module is already loaded) + one property load (state check for circular
dependencies) for modules that are already loaded.

Refs: #45659 (comment)
PR-URL: #45809
Reviewed-By: Daeyeon Jeong <daeyeon.dev@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Minwoo Jung <nodecorelab@gmail.com>
danielleadams pushed a commit that referenced this pull request Jan 4, 2023
The internal `require()` is actually just one map load (to see if the
module is already loaded) + one property load (state check for circular
dependencies) for modules that are already loaded.

Refs: #45659 (comment)
PR-URL: #45809
Reviewed-By: Daeyeon Jeong <daeyeon.dev@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Minwoo Jung <nodecorelab@gmail.com>
danielleadams pushed a commit that referenced this pull request Jan 5, 2023
The internal `require()` is actually just one map load (to see if the
module is already loaded) + one property load (state check for circular
dependencies) for modules that are already loaded.

Refs: #45659 (comment)
PR-URL: #45809
Reviewed-By: Daeyeon Jeong <daeyeon.dev@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Minwoo Jung <nodecorelab@gmail.com>
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This would need a non-semver-major version of #44483 to backport properly

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aduh95 commented Jan 23, 2023

@joyeecheung is it correct that you actually only need to pull from #44483 the changes made in lib/internal/validators.js and some of those made in lib/internal/bootstrap/browser.js? If so, that seems certainly feasible to do a non-semver-major backport. Otherwise, it seems very hard to backport anything else from that PR without risking breaking something somewhere.

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@aduh95 Not sure if this explanation makes sense - I need to pull in the changes to the module graph, ideally including some of the refactoring that reduces the conflicts

joyeecheung added a commit to joyeecheung/node that referenced this pull request Jan 30, 2023
It turns out that even with startup snapshots, there is a non-trivial
overhead for loading internal modules. This patch makes the loading
of the non-essential modules lazy again.

Caveat: we have to make some of the globals lazily-loaded too,
so the WPT runner is updated to test what the state of the global
scope is after the globals are accessed (and replaced with the
loaded value).

PR-URL: nodejs#45659
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Daeyeon Jeong <daeyeon.dev@gmail.com>
Reviewed-By: Jacob Smith <jacob@frende.me>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rafael Gonzaga <rafael.nunu@hotmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Minwoo Jung <nodecorelab@gmail.com>
Reviewed-By: Tierney Cyren <hello@bnb.im>
joyeecheung added a commit to joyeecheung/node that referenced this pull request Jan 30, 2023
It turns out that even with startup snapshots, there is a non-trivial
overhead for loading internal modules. This patch makes the loading
of the non-essential modules lazy again.

Caveat: we have to make some of the globals lazily-loaded too,
so the WPT runner is updated to test what the state of the global
scope is after the globals are accessed (and replaced with the
loaded value).

PR-URL: nodejs#45659
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Daeyeon Jeong <daeyeon.dev@gmail.com>
Reviewed-By: Jacob Smith <jacob@frende.me>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rafael Gonzaga <rafael.nunu@hotmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Minwoo Jung <nodecorelab@gmail.com>
Reviewed-By: Tierney Cyren <hello@bnb.im>
joyeecheung added a commit to joyeecheung/node that referenced this pull request Jan 30, 2023
It turns out that even with startup snapshots, there is a non-trivial
overhead for loading internal modules. This patch makes the loading
of the non-essential modules lazy again.

Caveat: we have to make some of the globals lazily-loaded too,
so the WPT runner is updated to test what the state of the global
scope is after the globals are accessed (and replaced with the
loaded value).

PR-URL: nodejs#45659
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Daeyeon Jeong <daeyeon.dev@gmail.com>
Reviewed-By: Jacob Smith <jacob@frende.me>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rafael Gonzaga <rafael.nunu@hotmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Minwoo Jung <nodecorelab@gmail.com>
Reviewed-By: Tierney Cyren <hello@bnb.im>
panva pushed a commit to joyeecheung/node that referenced this pull request Jan 31, 2023
It turns out that even with startup snapshots, there is a non-trivial
overhead for loading internal modules. This patch makes the loading
of the non-essential modules lazy again.

Caveat: we have to make some of the globals lazily-loaded too,
so the WPT runner is updated to test what the state of the global
scope is after the globals are accessed (and replaced with the
loaded value).

PR-URL: nodejs#45659
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Daeyeon Jeong <daeyeon.dev@gmail.com>
Reviewed-By: Jacob Smith <jacob@frende.me>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rafael Gonzaga <rafael.nunu@hotmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Minwoo Jung <nodecorelab@gmail.com>
Reviewed-By: Tierney Cyren <hello@bnb.im>
panva pushed a commit to joyeecheung/node that referenced this pull request Jan 31, 2023
It turns out that even with startup snapshots, there is a non-trivial
overhead for loading internal modules. This patch makes the loading
of the non-essential modules lazy again.

Caveat: we have to make some of the globals lazily-loaded too,
so the WPT runner is updated to test what the state of the global
scope is after the globals are accessed (and replaced with the
loaded value).

PR-URL: nodejs#45659
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Daeyeon Jeong <daeyeon.dev@gmail.com>
Reviewed-By: Jacob Smith <jacob@frende.me>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rafael Gonzaga <rafael.nunu@hotmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Minwoo Jung <nodecorelab@gmail.com>
Reviewed-By: Tierney Cyren <hello@bnb.im>
targos pushed a commit to joyeecheung/node that referenced this pull request Oct 28, 2023
It turns out that even with startup snapshots, there is a non-trivial
overhead for loading internal modules. This patch makes the loading
of the non-essential modules lazy again.

Caveat: we have to make some of the globals lazily-loaded too,
so the WPT runner is updated to test what the state of the global
scope is after the globals are accessed (and replaced with the
loaded value).

PR-URL: nodejs#45659
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Daeyeon Jeong <daeyeon.dev@gmail.com>
Reviewed-By: Jacob Smith <jacob@frende.me>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rafael Gonzaga <rafael.nunu@hotmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Minwoo Jung <nodecorelab@gmail.com>
Reviewed-By: Tierney Cyren <hello@bnb.im>
targos pushed a commit that referenced this pull request Nov 10, 2023
It turns out that even with startup snapshots, there is a non-trivial
overhead for loading internal modules. This patch makes the loading
of the non-essential modules lazy again.

Caveat: we have to make some of the globals lazily-loaded too,
so the WPT runner is updated to test what the state of the global
scope is after the globals are accessed (and replaced with the
loaded value).

PR-URL: #45659
Backport-PR-URL: #46425
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Daeyeon Jeong <daeyeon.dev@gmail.com>
Reviewed-By: Jacob Smith <jacob@frende.me>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rafael Gonzaga <rafael.nunu@hotmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Minwoo Jung <nodecorelab@gmail.com>
Reviewed-By: Tierney Cyren <hello@bnb.im>
sercher added a commit to sercher/graaljs that referenced this pull request Apr 25, 2024
It turns out that even with startup snapshots, there is a non-trivial
overhead for loading internal modules. This patch makes the loading
of the non-essential modules lazy again.

Caveat: we have to make some of the globals lazily-loaded too,
so the WPT runner is updated to test what the state of the global
scope is after the globals are accessed (and replaced with the
loaded value).

PR-URL: nodejs/node#45659
Backport-PR-URL: nodejs/node#46425
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Daeyeon Jeong <daeyeon.dev@gmail.com>
Reviewed-By: Jacob Smith <jacob@frende.me>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rafael Gonzaga <rafael.nunu@hotmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Minwoo Jung <nodecorelab@gmail.com>
Reviewed-By: Tierney Cyren <hello@bnb.im>
sercher added a commit to sercher/graaljs that referenced this pull request Apr 25, 2024
It turns out that even with startup snapshots, there is a non-trivial
overhead for loading internal modules. This patch makes the loading
of the non-essential modules lazy again.

Caveat: we have to make some of the globals lazily-loaded too,
so the WPT runner is updated to test what the state of the global
scope is after the globals are accessed (and replaced with the
loaded value).

PR-URL: nodejs/node#45659
Backport-PR-URL: nodejs/node#46425
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Daeyeon Jeong <daeyeon.dev@gmail.com>
Reviewed-By: Jacob Smith <jacob@frende.me>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rafael Gonzaga <rafael.nunu@hotmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Minwoo Jung <nodecorelab@gmail.com>
Reviewed-By: Tierney Cyren <hello@bnb.im>
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