[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]
Re: Global page into user processes (was: Re: Patch to cache TLS in %fp7 to avoid _lwp_getprivate syscalls)
On Wed, 18 Jan 2012 22:43:18 +0100
Joerg Sonnenberger <joerg%britannica.bec.de@localhost> wrote:
> On Wed, Jan 18, 2012 at 03:20:57PM -0500, Matthew Mondor wrote:
> > I noticed that the KERN_HARDCLOCK_TICKS sysctl(3) is still quite faster
> > than gettimeofday(2) (although it only exports a single int, the
> > hardclock(9)):
> Well, what timer are you using? Unless it is TSC or LAPIC, it is going
> to take significantly longer than the system call overhead or just
> reading a global variable.
This was with TSC. But the KERN_HARDCLOCK_TICKS sysctl knob appears
to export the hardclock_ticks global variable (at least on netbsd-5).
Main Index |
Thread Index |