On Mon, 2005-01-24 at 15:24 -0800, Christoph Lameter wrote: > On Mon, 24 Jan 2005, john stultz wrote: > > + /* convert to nanoseconds */ > > + ns_offset = cyc2ns(timesource, delta, NULL); > > + > > + /* apply the NTP scaling */ > > + ns_offset = ntp_scale(ns_offset); > > The monotonic clock is the time base for the gettime and gettimeofday > functions. This means ntp_scale() is called every time that the kernel or > an application access time. > > As pointed out before this will dramatically worsen the performance > compared to the current code base. > > ntp_scale() also will make it difficult to implement optimized arch > specific version of function for timer access. > > The fastcalls would have to be disabled on ia64 to make this work. Its > likely extremely difficult to implement a fastcall if it involves > ntp_scale().
Yep, performance is a big concern. Re-working ntp_scale() is still on my TODO list. I just didn't get to it in this release. Patches are always welcome. :) thanks for the feedback! -john - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
