Just in case it is of general interest: ZFS mirroring was the culprit in our case

[David Carter]

On Tue, 13 Nov 2007, Pascal Gienger wrote:

> Our latency problems went away like a miracle when we detached one half 
> of the mirror (so it is no more a mirror).
>
> Read-Rates are doubled (not per device, the total read rate!), latency 
> is cut off. No more latency problems.
>
> When attaching the volume again, resilvering puts the system to a halt -
> reads and writes do block for seconds (!).

Definitely of interest to those of us keeping one eye on ZFS. Thanks. Can 
someone else running ZFS confirm this behaviour?

-- 
David Carter                             Email: David.Carter at ucs.cam.ac.uk
University Computing Service,            Phone: (01223) 334502
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