[linux-lvm] Testing the new LVM cache feature

[Richard W.M. Jones]

On Fri, May 30, 2014 at 09:55:29AM -0400, Mike Snitzer wrote:
> So unless you have misaligned IO you _should_ be able to avoid reading
> from the origin.  But XFS is in play here.. I'm wondering if it is

The filesystem is ext4.

> If you set read_promote_adjustment to 0 it should pull the associated
> blocks into the cache.  What makes you think it isn't?

The fio test is about twice as fast as when I ran the fio test
directly on the hard disk array.  This test runs about 5 times slower
than when I ran it directly on the SSD.

I'm not measuring the speed of the md5sum operation.

Rich.

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