bootstrap: optimize modules loaded in the built-in snapshot

[joyeecheung]

To make the patch easier to review I have split it into smaller commits, though it's probably also okay to review the entire diff since most of the changes are superficial.

Locally I got:

                                                                                     confidence improvement accuracy (*)   (**)  (***)
misc/startup.js count=30 mode='process' script='benchmark/fixtures/require-builtins'        ***      4.14 %       ±0.59% ±0.79% ±1.03%
misc/startup.js count=30 mode='process' script='test/fixtures/semicolon'                    ***     11.11 %       ±0.75% ±1.00% ±1.30%
misc/startup.js count=30 mode='worker' script='benchmark/fixtures/require-builtins'         ***      3.67 %       ±0.73% ±0.97% ±1.27%
misc/startup.js count=30 mode='worker' script='test/fixtures/semicolon'                     ***     10.93 %       ±0.90% ±1.20% ±1.56%

bootstrap: support module_wrap binding in snapshot

bootstrap: include event_target into the built-in snapshot

Since the module has to be loaded during bootstrap anyway.

modules: move modules/cjs/helpers.js to modules/helpers.js

The helpers are actually shared by the two loaders, so move them
under modules/ directly.

lib: add getLazy() method to internal/util

This patch adds a getLazy() method to facilitate initialize-once
lazy loading in the internals.

lib: lazy-load deps in source_map_cache.js

So that the file can be snapshotted.

lib: lazy-load deps in modules/run_main.js

So that the file can be snapshotted

modules: move callbacks and conditions into modules/esm/utils.js

This moves the following utils into modules/esm/utils.js:

• Code related to default conditions
• The callbackMap (which is now created in the module instead of
  hanging off the module_wrap binding, since the C++ land
  does not need it).
• Per-isolate module callbacks

These are self-contained code that can be included into the
built-in snapshot.

bootstrap: make CJS loader snapshotable

This patch makes the top-level access to runtime states in the
CJS loader lazy, and move the side-effects into a
initializeCJS() function that gets called during pre-execution.
As a result the CJS loader can be included into the built-in
snapshot.

bootstrap: optimize modules loaded in the built-in snapshot

Preload essential modules and lazy-load non-essential ones.
After this patch, all modules listed by running this snippet:

const list = process.moduleLoadList.join('\n');
require('fs').writeSync(1, list, 'utf-8');

(which is roughly the same list as the one in
test-bootstrap-module.js for the main thread)
are loaded from the snapshot so no additional compilation cost
is incurred.

[nodejs-github-bot]

Review requested:

• @nodejs/modules
• @nodejs/startup
• @nodejs/vm

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/48458/

[GeoffreyBooth]

What’s the relationship between this PR and #45828? Is this just the first of the several commits you mentioned?

[joyeecheung]

@GeoffreyBooth This is a trimmed down version of #45828 that does not attempt to snapshot the ESM loader (except some really small bits)

[GeoffreyBooth]

Okay, well even still this seems like a significant improvement. The benchmarks you posted here are almost as good as in #45828, so it seems like you’ve achieved the bulk of the performance boost already in this PR alone.

[joyeecheung]

From the CI: https://ci.nodejs.org/view/Node.js%20benchmark/job/benchmark-node-micro-benchmarks/1264/

02:34:00                                                                                      confidence improvement accuracy (*)   (**)  (***)
02:34:01 misc/startup.js count=30 mode='process' script='benchmark/fixtures/require-builtins'        ***      3.32 %       ±0.84% ±1.11% ±1.45%
02:34:01 misc/startup.js count=30 mode='process' script='test/fixtures/semicolon'                    ***     10.02 %       ±1.17% ±1.57% ±2.04%
02:34:01 misc/startup.js count=30 mode='worker' script='benchmark/fixtures/require-builtins'         ***      5.03 %       ±0.90% ±1.20% ±1.56%
02:34:01 misc/startup.js count=30 mode='worker' script='test/fixtures/semicolon'                     ***     11.24 %       ±1.27% ±1.69% ±2.21%

[GeoffreyBooth]

Thanks for doing this. I can’t speak for the bootstrap parts but the module refactors look great!

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/48483/

[bnoordhuis]

#45551 needs to be backported first

@juanarbol that's been done. This PR and #46225 should be unblocked now?