Script:
const now = performance.now();
process.report.getReport()
console.log(`Took ${performance.now() - now}ms`);On Node 20.2.0:
> node get-report.js
Took 26.467950999736786ms
On node 20.3.0
> node get-report.js
609.6318630054593ms
I did a bisect and the commit that introduced this slowdown was bfcb3d1, which is the upgrade of libuv.
But the actual problem was introduced (I think) at libuv/libuv@434eb4b, the slowdown is caused because instead of assuming the same information for all CPUs, now libuv read the /sys/devices/system/cpu/cpu%u/cpufreq/scaling_cur_freq for every CPU.
I'll also open an issue on libuv, but I want to keep it open just to track this slowdown.
My machine:
- Ryzen 9 5950X 3.4GHz, 16-Cores 32-Threads
- 32GB of Memory.
cc @nodejs/performance
Script:
On Node 20.2.0:
On node 20.3.0
I did a bisect and the commit that introduced this slowdown was bfcb3d1, which is the upgrade of
libuv.But the actual problem was introduced (I think) at libuv/libuv@434eb4b, the slowdown is caused because instead of assuming the same information for all CPUs, now
libuvread the/sys/devices/system/cpu/cpu%u/cpufreq/scaling_cur_freqfor every CPU.I'll also open an issue on
libuv, but I want to keep it open just to track this slowdown.My machine:
cc @nodejs/performance