Re: [ANNOUNCE] ktimers subsystem

Thomas Gleixner
2005-09-25T20:59:40Z

On Sun, 2005-09-25 at 01:45 +0200, Roman Zippel wrote:

> > The backward conversion from nsec_t to timespec is almost a non issue.
> > The vast majority of callers dont provide the second argument to
> > nanosleep(), setitimer(), set_timer() which makes the conversion
> > necessary and I think we optimize for the common use case.
>
> You know very well, that the conversion back to timespec is the killer in
> your calculation. You graciously decide that the "vast majority" doesn't
> want to read the timer, how did you get to that conclusion?

I graciously put instrumentation into _all_ the relevant syscalls on a
desktop and a server machine. The result is that less than 1% of the
calls provide the read back variable.

tglx