Re: 30 TB RAID6 + XFS slow write performance

Michael Monnerie
2011-07-20T14:04:38Z

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On Mittwoch, 20. Juli 2011 Stan Hoeppner wrote:
> I thought this was packing multiple small files into
> a single stripe write, which you just explained XFS does not do.

This is interesting, I jump in here. Does that mean that if I have a XFS
volume with sw=14,su=64k (14*64=896KiB) that when I write 10 small files
in the same dir with 2KB each, each file would be placed at a 896KiB
boundary? That way, all stripes of a 1GB partition would be full when
there are roughly 1170 files (1170*896KiB ~ 1GB). What would happen when
I create other files - is XFS "full" then, or would it start using sub-
stripes? If sub-stripes, would they start at su (=64KiB) distances, or
at single block (e.g. 4KiB) distances?

I hope I could explain my thoughts in an understandable way ;-)

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