Re: Login time

[Michael Meeks <michael meeks novell com>]

On Thu, 2007-04-12 at 22:29 +0200, Soeren Sandmann wrote:
> What I think is going on is that strace greatly exaggerates the time
> to do each system call so it tends to produce inflated numbers for
> kernel time vs user time.

	To put some numbers to this - OO.o does about ~20k system calls on
writer startup [ this is rather excessive - but lets not go there ],
startup with strace -f -o /tmp/log [1] takes ~3 seconds, and without it
takes ~2.5 seconds (both warm, 3 runs etc.)

	That yields a penalty of 500ms for 20,000 system calls which is 
25us per call - which (on the whole) seems a reasonably low overhead for
a more reasonable application that does fewer syscalls. ie. it shouldn't
be -that- bad :-)

	HTH,

		Michael.

[1] - don't churn it to a terminal of course or you'll get really bad
performance & odd effects.
-- 
 michael meeks novell com  <><, Pseudo Engineer, itinerant idiot