Re: ext2fs kernel profiling: most of the time in thread management

[Svante Signell]

On Thu, 2011-12-29 at 01:25 +0100, Samuel Thibault wrote:
> Hello,
> 
> I've done some stat-based kernel profiling (I'll have to post how to do
> it on the wiki sometime) on ext2fs doing nothing more than
> 
> while true; do rm -f blop ; \cp -f blip blop ; done

> It might be biaised by the clock not being able to tick everywhere in
> the kernel (though I guess e.g. most of the IPC machinery is running at
> ipl0?), but I believe it's still a bit revealing: I had already noticed
> that ext2fs spends most of its time in the kernel (like 90%), and it
> here seems we're spending a lot of time just managing the ext2fs thread
> sleeps (no, there aren't many threads in that test, just two dozen).

It's hard to relate these numbers without comparison: What are the
corresponding numbers for Linux/kFreeBSD?