Re: [patch] zero-bounce block highmem I/O, #13

Jens Axboe
2001-08-28T12:40:38Z

On Tue, Aug 28 2001, Christoph Rohland wrote:
> Hi Jens,
>
> On Tue, 28 Aug 2001, Jens Axboe wrote:
> > Ok found the bug -- SCSI was accidentally using blk_seg_merge_ok
> > when it just wanted to test if we were crossing a 4GB physical
> > address boundary or not. Doh! Attached incremental patch should fix
> > the SCSI performance issue. I'm testing right now...
>
> Yup, performance is back to 2.4.9 level. But I do not see an
> improvement.
>
> I will now do a database import.

Of course it depends on the type of work load how big an improvement you
see. How much RAM is in the machine?

It would be interesting to see profiles of stock + highmem kernels.

--
Jens Axboe