Re: [PATCH][2.6-mm] Readahead issues and AIO read speedup

[Jens Axboe]

On Thu, Aug 07 2003, Joel Becker wrote:
> On Thu, Aug 07, 2003 at 09:28:00AM -0700, Andrew Morton wrote:
> > If the database pagesize is 16k then the application should be submitting
> > 16k reads, yes?  If so then these should not be creating 4k requests at the
> > device layer!  So what we need to do is to ensure that at least those 16k
> 
> 	Um, I thought bio enforced single CDB I/O for contiguous chunks
> of disk!  If it doesn't, 2.6 is just as lame as 2.4.

It does of course, that was one of the main points of the bio structure.
->readpages() can submit those 16k minimum chunks in one bio.

-- 
Jens Axboe

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