example writeFile benchmark:
```
# before
time 188 ms rate 53191
time 168 ms rate 59523
time 167 ms rate 59880
time 166 ms rate 60240
time 168 ms rate 59523
time 173 ms rate 57803
time 183 ms rate 54644
# after
time 157 ms rate 63694
time 152 ms rate 65789
time 151 ms rate 66225
time 151 ms rate 66225
time 152 ms rate 65789
```
This revert has been discussed at length out-of-band (including with
@andreubotella). The realms work in impeding ongoing event loop and
performance work. We very much want to land realms but it needs to wait
until these lower-level refactors are complete. We hope to bring realms
back in a couple weeks.
The `JsRuntimeState` struct stores a number of JS callbacks that are
used either in the event loop or when interacting with V8. Some of
these callback fields are vectors of callbacks, and therefore could
plausibly store at least one callback per realm. However, some of
those fields are `Option<v8::Global<v8::Function>>`, which would make
the callbacks set by a realm override the one that might have been set
by a different realm.
As it turns out, all of the current such optional callbacks
(`js_promise_reject_cb`, `js_format_exception_cb` and
`js_wasm_streaming_cb`) are only used from inside a realm, and
therefore this change makes it so such callbacks can only be set from
inside a realm, and will only affect that realm.
Pull request #14019 enabled initial support for realms, but it did not
include support for async ops anywhere other than the main realm. The
main issue was that the `js_recv_cb` callback, which resolves promises
corresponding to async ops, was only set for the main realm, so async
ops in other realms would never resolve. Furthermore, promise ID's are
specific to each realm, which meant that async ops from other realms
would result in a wrong promise from the main realm being resolved.
This change creates a `ContextState` struct, similar to
`JsRuntimeState` but stored in a slot of each `v8::Context`, which
contains a `js_recv_cb` callback for each realm. Combined with a new
list of known realms, which stores them as `v8::Weak<v8::Context>`,
and a change in the `#[op]` macro to pass the current context to
`queue_async_op`, this makes it possible to send the results of
promises for different realms to their realm, and prevent the ID's
from getting mixed up.
Additionally, since promise ID's are no longer unique to the isolate,
having a single set of unrefed ops doesn't work. This change therefore
also moves `unrefed_ops` from `JsRuntimeState` to `ContextState`, and
adds the lengths of the unrefed op sets for all known realms to get
the total number of unrefed ops to compare in the event loop.
Co-authored-by: Luis Malheiro <luismalheiro@gmail.com>
Relanding #12994
This commit adds support for "unhandledrejection" event.
This event will trigger event listeners registered using:
"globalThis.addEventListener("unhandledrejection")
"globalThis.onunhandledrejection"
This is done by registering a default handler using
"Deno.core.setPromiseRejectCallback" that allows to
handle rejected promises in JavaScript instead of Rust.
This commit will make it possible to polyfill
"process.on("unhandledRejection")" in the Node compat
layer.
Co-authored-by: Colin Ihrig <cjihrig@gmail.com>
The `op_event_loop_has_more_work` op, introduced in #14830, duplicates
code from `JsRuntime::poll_event_loop`. That PR also added the unused
method `JsRuntime::event_loop_has_work`, which is another duplication
of that same code, and which isn't used anywhere.
This change deduplicates this by renaming
`JsRuntime::event_loop_has_work` to `event_loop_pending_state`, and
making it the single place to determine what in the event loop is
pending. This result is then returned in a struct which is used both
in the event loop and in the `op_event_loop_has_more_work` op.
This commit adds support for "unhandledrejection" event.
This event will trigger event listeners registered using:
"globalThis.addEventListener("unhandledrejection")
"globalThis.onunhandledrejection"
This is done by registering a default handler using
"Deno.core.setPromiseRejectCallback" that allows to
handle rejected promises in JavaScript instead of Rust.
This commit will make it possible to polyfill
"process.on("unhandledRejection")" in the Node compat
layer.
Co-authored-by: Colin Ihrig <cjihrig@gmail.com>
Keep a cache for source maps and source lines.
We sort of already had a cache argument for source map lookup
functions but we just passed an empty map instead of storing it.
Extended it to cache source line lookups as well and plugged it
into runtime state.
