Re: OSDL DBT-2 AS vs. Deadline 2.5.68-mm2

Mark Haverkamp (markh@osdl.org)
07 May 2003 10:39:11 -0700


On Wed, 2003-05-07 at 10:36, Jens Axboe wrote:
> On Wed, May 07 2003, markw@osdl.org wrote:
> > On 7 May, Jens Axboe wrote:
> > > On Wed, May 07 2003, markw@osdl.org wrote:
> > >> I've collected some data from STP to see if it's useful or if there's
> > >> anything else that would be useful to collect. I've got some tests
> > >> queued up for the newer patches, but I wanted to put out what I had so
> > >> far.
> > >>
> > >>
> > >> METRICS OVER LAST 20 MINUTES:
> > >> --------------- -------- ----- ---- -------- -----------------------------------
> > >> Kernel Elevator NOTPM CPU% Blocks/s URL
> > >> --------------- -------- ----- ---- -------- -----------------------------------
> > >> 2.5.68-mm2 as 1155 94.3 8940.2 http://khack.osdl.org/stp/271356/
> > >> 2.5.68-mm2 deadline 1255 94.9 9598.7 http://khack.osdl.org/stp/271359/
> > >>
> > >> FUNCTIONS SORTED BY TICKS:
> > >> -- ------------------------- ------- ------------------------- -------
> > >> # as 2.5.68-mm2 ticks deadline 2.5.68-mm2 ticks
> > >> -- ------------------------- ------- ------------------------- -------
> > >> 1 default_idle 6103428 default_idle 5359025
> > >> 2 bounce_copy_vec 86272 bounce_copy_vec 97696
> > >> 3 schedule 63819 schedule 70114
> > >> 4 __make_request 30397 __blk_queue_bounce 31167
> > >> 5 __blk_queue_bounce 26962 scsi_request_fn 26623
> > >> 6 scsi_request_fn 24845 __make_request 25012
> > >
> > > uhh nasty, you are spending a lot of time bouncing. How much RAM is in
> > > the machine, and what is the scsi hba?
> >
> > The system has 4GB of memory and has a DECchip 21554 (aacraid) that the
> > external drives are connected to. Mark Haverkamp is currently trying to
> > address those bounce buffers.
>
> aacraid actually looks sane enough. so you should just be able to set
> host->highmem_io and it should work.

That is what I thought, but I wanted to get a machine with lots of
memory to try it out on.

Mark.

-- 
Mark Haverkamp <markh@osdl.org>

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