On Sat, Nov 15, 2008 at 10:52 AM, Richard Scobie [off-list ref] wrote:

Dan Williams wrote:

quoted

By default MD tries to be fair and allow partially written stripes the
same access to the disk as fully written stripes to prevent starvation
for little writers.  However, you can sometimes eek out more streaming
performance at the cost of fairness by increasing this value (where 0
== never let a preread pass a full-stripe-write).

I believe XFS optimises for full stripe writes, so perhaps this setting is
of more benefit for other file systems?

Not really.  XFS was used when benchmarking this change [1] and was
able to measure a performance gain.

[1] http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=8b3e6cdc53b7f29f7026955d6cb6902a49322a15