linux LVM mirror vs. MD mirror

Posted by sims on Server Fault See other posts from Server Fault or by sims
Published on 2010-03-27T07:26:45Z Indexed on 2010/03/27 7:33 UTC
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lvm

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mdadm

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mirror

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log

I think I remember making some mirrors years ago with LVM, and I don't remember this "log" thing. Or maybe I made the mirror with mdadm and put LVM on top. That must be it.

What is the LVM log for if it is just a mirror? What is stored there? What is it's purpose? Is using "--mirrorlog core" bad? What's the down side? I don't want to have to have another partition for logs if I don't have to.
Any recommendations on using either technology? Even if I make the mirror with mdadm, I'll use LVM on top of that. So, in that case, maybe it's better to have the whole setup built with LVM...? Would that take more a performance hit or less?

The disks are for storing Xen domU "disks".

Sorry for the complex not-to-the-point "question".

Ideas and suggestions and links are most welcome. Thanks!

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