Re: USB performance bug since kernel 2.6.13 (CRITICAL???)

Alan Cox
2006-10-13T23:58:21Z

Ar Gwe, 2006-10-13 am 16:30 -0700, ysgrifennodd Open Source:
> There is an ioctl that is waiting for the URB to be reaped.
> I am almost certain it is this syscall that is taking 4 ms (as
> opposed to 1 ms with CONFIG_HZ=1000).

What does strace say about it ? This is measurable not speculation.

> Will the first piece of code wake up immediately or only after the
> next HZ timeslice? If it is the latter, which is what I am starting to

It depends if there are other things running and on their priority
relative to you.