Currently V8 only checks that the length of the source code is the
same as the code used to generate the hash, so we add an additional
check here:
1. During compile time, when generating node_javascript.cc and
node_code_cache.cc, we compute and include the hash of the
(unwrapped) JavaScript source in both.
2. At runtime, we check that the hash of the code being compiled
and the hash of the code used to generate the cache
(inside the wrapper) is the same.
This is based on the assumptions:
1. `internalBinding('code_cache_hash')` must be in sync with
`internalBinding('code_cache')` (same C++ file)
2. `internalBinding('natives_hash')` must be in sync with
`process.binding('natives')` (same C++ file)
3. If `internalBinding('natives_hash')` is in sync with
`internalBinding('natives_hash')`, then the (unwrapped)
code used to generate `internalBinding('code_cache')`
should be in sync with the (unwrapped) code in
`process.binding('natives')`
There will be, however, false positives if the wrapper used
to generate the cache is different from the one used at run time,
and the length of the wrapper somehow stays the same.
But that should be rare and can be eased once we make the
two bootstrappers cached and checked as well.
PR-URL: https://github.com/nodejs/node/pull/22152
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Tiancheng "Timothy" Gu <timothygu99@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Gus Caplan <me@gus.host>
This patch makes it possible to generate the code cache
for the builtins directly from the original script object
(instead of compiling a new one) and after the script has
been run (via `NativeModule.require`). Before this patch
only the top level functions (the wrapped ones)
are included in the cache, after this patch the inner
functions in those modules will be included as well.
Also blacklists modules from dependencies like V8 and
node-inspect since we cannot guarantee that they are suitable
to be executed directly.
PR-URL: https://github.com/nodejs/node/pull/21567
Refs: https://github.com/nodejs/node/issues/21563
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Tiancheng "Timothy" Gu <timothygu99@gmail.com>
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: John-David Dalton <john.david.dalton@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
This patch speeds up the startup time and reduce the startup memory
footprint by using V8 code cache when comiling builtin modules.
The current approach is demonstrated in the `with-code-cache`
Makefile target (no corresponding Windows target at the moment).
1. Build the binary normally (`src/node_code_cache_stub.cc` is used),
by now `internalBinding('code_cache')` is an empty object
2. Run `tools/generate_code_cache.js` with the binary, which generates
the code caches by reading source code of builtin modules off source
code exposed by `require('internal/bootstrap/cache').builtinSource`
and then generate a C++ file containing static char arrays of the
code cache, using a format similar to `node_javascript.cc`
3. Run `configure` with the `--code-cache-path` option so that
the newly generated C++ file will be used when compiling the
new binary. The generated C++ file will put the cache into
the `internalBinding('code_cache')` object with the module
ids as keys
4. The new binary tries to read the code cache from
`internalBinding('code_cache')` and use it to compile
builtin modules. If the cache is used, it will put the id
into `require('internal/bootstrap/cache').compiledWithCache`
for bookkeeping, otherwise the id will be pushed into
`require('internal/bootstrap/cache').compiledWithoutCache`
This patch also added tests that verify the code cache is
generated and used when compiling builtin modules.
The binary with code cache:
- Is ~1MB bigger than the binary without code cahe
- Consumes ~1MB less memory during start up
- Starts up about 60% faster
PR-URL: https://github.com/nodejs/node/pull/21405
Reviewed-By: John-David Dalton <john.david.dalton@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Gus Caplan <me@gus.host>
