[linux-lvm] Paralell IO performance with LVM and XFS

[Russell Coker]

On Thu, 17 Jan 2002 16:21, Patrick Caulfield wrote:
> On Thu, Jan 17, 2002 at 01:56:39PM +0100, Russell Coker wrote:
> > Striping across 4 disks will never give you 4* the throughput of 1 disk,
> > but you would hope for double the throughput.
>
> A graph of some tests I did using bonnie++ and striping on fibre-channel
> disks is online at http://www.cix.co.uk/~tykepenguin/stripetest.png

Firstly, I suggest that you skip the per-char tests when graphing such 
things, it's generally not very interesting and just clutters the graph.

Next the seeks, block-io, and create/delete test results belong on different 
graphs because the Y axis measures different things, and because it needs 
different scales.

Finally what graphing program did you use?

> The most obvious bottleneck there was the actually FC interface which ran
> out of capacity at 3 stripes.

Why are you so certain that it's the FC interface at fault?  The FC interface 
should be able to do more than 60MB/s.

-- 
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