On 2014-09-24 0:09, Stan Hoeppner wrote:
> If you create any striped arrays, especially parity arrays, with md make
> sure to manually specify chunk size and match it to your workload. The
> current default is 512KB. This is too large for a great many workloads,
> specifically those that are metadata heavy or manipulate many small
> files. 512KB wastes space and with parity arrays causes RMW, hammering
> throughput and increasing latency.
Thanks again for the valueable information.
I used to work with databases on storage subsystems, so placing GBs of
database containers for tableapaces on arrays with a larger stripe size
was actually beneficial.
For log files and other data I usually used different cache settings and
So how does this work with SW RAID?
Does the XFS chunk size equal the amount of data touched by a single r/w
I'm asking because data is usually written in page/extent sizes for
databases. Even if I have a container with 50GB, I might only have to
read/write a 4k page.
regards Helmut K. C. Tessarek
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await thee at its end.