On Tue, Jan 29, 2002 at 09:20:10PM -0500, Robert Love wrote:
> On Tue, 2002-01-29 at 20:26, Andrew Morton wrote:
> > Just a little word of caution here. Remember the
> > apache-flock-synchronisation fiasco, where removal
> > of the BKL halved Apache throughput on 8-way x86.
> > This was because the BKL removal turned serialisation
> > on a quick codepath from a spinlock into a schedule().
> I feared this too, but eventually I decided it was worth it and
> benchmarks backed that up. If nothing else this is yet-another-excuse
> for locks that can spin-then-sleep.
> I posted dbench results, which show a positive gain even on 2-way for
> multiple client loads.
Luckily, apache on its own doesn't seem to use lseek() when sending the
file - it seems to be an open, mmap, write. (apache 1.3.22)
However, php with apache does do an lseek on the target script. Now
remember the /. effect... You'll be accessing the same file from
several apache or php processes.
-- Russell King (email@example.com) The developer of ARM Linux http://www.arm.linux.org.uk/personal/aboutme.html - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to firstname.lastname@example.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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