On Tue, Aug 23, 2005 at 02:32:36PM +0200, Jens Axboe wrote:
> Hi,
> 
> This is a little something I have played with. It allows you to see
> exactly what is going on in the block layer for a given queue. Currently
> it can logs request queueing and building, dispatches, requeues, and
> completions.

Ah, fabulous.  Thanks Jens!

> +     t.magic         = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION;
> +     t.sequence      = atomic_add_return(1, &bt->sequence);
> +     t.time          = sched_clock() / 1000;

Wouldn't it be better to pass out the highest precision available here
& then do the conversion in userspace instead?  I guess one might want
that little bit more for a RAM disk or something ... actually, talking
to one of the SGI people here with alot of experience on IRIX with a
similar facility, the msec resolution there is apparently sometimes an
issue already with fast storage.

cheers.

-- 
Nathan
-
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/

Reply via email to