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a08a10262a
The rust standard library has a fast path for process spawning, where it
will use `posix_spawn` instead of `fork` + `exec`. In order to take that
fast path, you can't have a `pre_exec` hook and you have to pass an
absolute path for the program path.
We were already resolving the program path, but we were unconditionally
doing a `pre_exec` hook. This PR makes the `pre_exec` hook conditional,
which lets us take the fast path in most cases.
**Results**
on an m3 max
canary:
```
took 318755.68ms
```
this PR:
```
took 17184.64ms
```
So an improvement from 318.76 seconds to 17.18 seconds, or about 18.5x
faster
**Benchmark**:
```js
import { fileURLToPath } from "node:url";
const performance = globalThis.performance;
const __filename = fileURLToPath(import.meta.url);
async function spawn() {
const child = new Deno.Command("cat", {
args: [__filename],
stderr: "null",
stdin: "null",
stdout: "null",
}).spawn();
await child.status;
}
async function spawn100() {
const procs = [];
for (let i = 0; i < 100; i++) {
procs.push(spawn());
}
await Promise.all(procs);
}
const start = performance.now();
for (let i = 0; i < 1000; i++) {
console.log(`on ${(i + 1) * 100}`);
await spawn100();
}
const end = performance.now();
console.log(`took ${end - start}ms`);
```
|
||
|---|---|---|
| .. | ||
| 40_process.js | ||
| Cargo.toml | ||
| ipc.rs | ||
| lib.rs | ||
| README.md | ||
deno_process
This crate implements subprocess APIs for Deno