Re: Remote NAS

[adfas asd <chimera_god@yahoo.com>]

--- On Wed, 9/23/09, Keld Jørn Simonsen <keld@dkuug.dk> wrote:
> Writes are about the same for RAID10 types and RAID1.
> This is also what theory would tell for random writes,
> given that they
> are random, and that the elevator algorithm of the file
> system optimizes
> the writing. 
> 
> Yes, offset came after far, but Neil Brown said that offset
> was
> implemented to make Linux MD align to RAID standards. It
> was not
> necessarily meant to be better than far. 
> 
> I think it is hard to beat raid10 far on reads (but then I
> am also the
> one that invented the layout). As said for random reading
> and writing
> the theory says that all mirrored raid types perform
> equally, and tests
> verify this. Maybe far layout even has an edge for random
> reading, in
> theory it should, but I have not seen tests really
> verifying that.

Excellent, thanks Keld.




      
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