Re: [RFC] [PATCH] 2.5.35 patch for making DIO async

[Benjamin LaHaise <bcrl@redhat.com>]

On Wed, Sep 18, 2002 at 08:58:22AM -0700, Badari Pulavarty wrote:
> Thanks for looking at the patch. Patch needed few cleanups to get it
> working. Here is the status so far..
> 
> 1) I tested synchronous raw read/write. They perform almost same as
>    without this patch. I am looking at why I can't match the performance.
>    (I get 380MB/sec on 40 dd's on 40 disks without this patch.
>     I get 350MB/sec with this patch).

Hmm, we should try to improve that.  Have you tried profiling a long run?

> 2) wait_on_sync_kiocb() needed blk_run_queues() to make regular read/
>    write perform well.

That should be somewhat conditional, but for now it sounds like the right 
thing to do.

> 3) I am testing aio read/writes. I am using libaio.0.3.92. 
>    When I try aio_read/aio_write on raw device, I am get OOPS.
>    Can I use libaio.0.3.92 on 2.5 ? Are there any interface
>    changes I need to worry  between 2.4 and 2.5 ?

libaio 0.3.92 should work on 2.5.  Could you send me a copy of the 
decoded Oops?

		-ben
-- 
GMS rules.