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Re: changing raid level?

On Wed, 28 Jan 2009 11:17:22 +0100
Manuel Bouyer <> wrote:

> On a slow CPU the read+read+compare+write is killing the whole system
> (mostly the "compare" I think) with 90% of the cpu working on this.
> A simple read+write is much, much better on such a setup (the system
> is still useable while doing a raid1 reconstruct). It matters
> even on a fast CPU, when both disks are able to provide data at 180MB/s.
> The system is still useable but comptationnal tasks (esp. network
> encryption) is much, much slower.

If the problem is CPU usage more than I/O, could a thread running at a
lower (higher) priority help for this?


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