Re: READAHEAD

From: Andrew Morton
Date: Fri Oct 31 2003 - 03:02:25 EST


Nuno Silva <nuno.silva@xxxxxxxxxxxx> wrote:
>
> >> Before, i never had to set readahead so high
> >> Please could you tell me, what is going on here ?
> >
> >
> > Lots of people have been reporting this. It's rather weird.
> >
>
> I know nothing about this but, FWIW, I think that what changed where the
> units. With 2.4 you specify sectors, with 2.6 you specify bytes.
>
> So, having -a8, in 2.4, is the same as having -a$((8*512)) [it's 4096
> :)], in 2.6.
>

No, everything seems OK. Both `hdparm -a' and `blockdev --setra' are
operating in units of 512 bytes.

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