[linux-lvm] Testing the new LVM cache feature

[Richard W.M. Jones]

On Fri, May 30, 2014 at 09:38:14AM -0400, Mike Snitzer wrote:
> Why are you setting {read,write}_promote_adjustment to 1?  I asked you
> to set write_promote_adjustment to 0.

I didn't realize there would be (much) difference.  However I
will certainly try it with write_promote_adjustment == 0.

> Your random fio job won't hit the same blocks, and md5sum likely uses
> buffered IO so unless you set 0 for both the cache won't aggressively
> cache like you're expecting.

Right, that was definitely a mistake!  I will drop_caches between each
md5sum operation.

Rich.

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