XFS: Abysmal write performance because of excessive seeking (allocation groups to blame?)

[Emmanuel Florac]

Le Sat, 7 Apr 2012 09:27:50 +0200 vous écriviez:

> So it sounds like that for poor guys like us, who can’t afford the
> hardware to have dozens of spindles, the best option would be to
> create the XFS file system with agcount=1? That seems to be the only
> reasonable conclusion to me, since a single RAID device, like a single
> disk, cannot write in parallel anyway.

You best option is to buy a SSD. Seriously, even a basic decent consumer
model will bury your array in the dust. Also, recent RAID controllers
from LSI and Adaptec are able to "enhance" a spinning rust array by
using an SSD as a cache.

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