Andrei Maslennikov wrote:
On 4/13/07, *Brian J. Murrell* <brian-KYPl3Ael/zSakBO8gow8eQ@xxxxxxxxxxxxxxxx
<mailto:brian-KYPl3Ael/zSakBO8gow8eQ@xxxxxxxxxxxxxxxx>> wrote:
On Fri, 2007-13-04 at 17:30 +0200, Andrei Maslennikov wrote:
> Time ago we have however considered and discarded this solution
as we
> wanted to ensure that every file is confined to one and only one
OSS capable
> to deliver 0.9-1 GB/sec.
Do you really mean OSS here or OST? Given the 3 OSTs you would put on
the 3 RAID cards you have in your OSS, this would meet your
requirements
wouldn't it?
Hi Brian,
I meant OSS here. If our configuration would include only one OSS
with 3 OSTs
and the default stripe count for the file system would be 3, the
solution mentioned
by Andreas would be ok (and we have even considered it before asking
the first
question on this list). The point is, if we would be adding other
3-OST-based OSS
machines to the same file system, it may so happen that the files may
end up
on different OSS machines (with a default stripe count of 3 one file
may be split
over 3 OSTs in three different OSS hosts).
Our main requirement is to ensure that every file ends up in one
and only
one OSS box. If this is not possible with the multi-OST OSS machines, we
may only be able to use one OST per OSS, and hence will have to
stay with
max 750 MB/sec single file performance per OSS.
Best regards - Andrei.
You can use 'lfs setstripe' to designate a starting OST index, for a
file or a directory. With that, you could set up different single-OSS
directories.
If you have more than a single client reading from an OSS at the same
time, you don't even need to do that -- use three OSTs per OSS, with
everything single-striped. Your multiple clients can use the different
OSTs simultaneously, increasing your total performance.
