On Thu, 05 Apr 2007 03:39:29 -0400 Rik van Riel <[EMAIL PROTECTED]> wrote:
> Rik van Riel wrote: > > > MADV_DONTNEED, unpatched, 1000 loops > > > > real 0m13.672s > > user 0m1.217s > > sys 0m45.712s > > > > > > MADV_DONTNEED, with patch, 1000 loops > > > > real 0m4.169s > > user 0m2.033s > > sys 0m3.224s > > I just noticed something fun with these numbers. > > Without the patch, the system (a quad core CPU) is 10% idle. > > With the patch, it is 66% idle - presumably I need Nick's > mmap_sem patch. > > However, despite being 66% idle, the test still runs over > 3 times as fast! Please quote the context switch rate when testing this stuff (I use vmstat 1). I've seen it vary by a factor of 10,000 depending upon what's happening. - 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/
