[linux-lvm] md + lvm + reiser

[Xavier Montagutelli]

On Sat, 7 Sep 2002, Chris Jantzen wrote:

> Excuse me if this has been covered already, though I did try to read
> through the archives. I am running md raid5 (software) over several
> drives and importing that into LVM and using reiserfs. It's worked fine
> for some time, but now I want to start snapshots. I've learned about the
> VFS lock patch, yes, but my real question is: why is the raid5 buffer
> cache constantly thrashing back and forth? I assume this has to do with
> a conflict between reiserfs's 4096 byte blocks and LVM's 512
> SECTOR_SIZE. Or did I configure something wrong somewhere? Is it safe to
> just change SECTOR_SIZE in lvm.h or will that mess up on-disk
> structures? Thank you.

I have exactly the same symptoms with the same configuration (md + lvm +
reiser) ; the raid5 cache size keeps changing when I start using
snapshots. Does someone have some tips to avoid/explain this ?


--
[ Xavier Montagutelli          `""'                                   ]
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