(original article)

Re: Converting RAID5 to RAID6 and other shape changing in md/raid

31 July 2010, 08:15 UTC

I'm using ubuntu and don't have the latest mdadm. Ubuntu uses v2.6.7.1

I want to reshape a RAID5 (3x 1TiB) and change the chunk size. I have read that increasing chunk size can greatly improve performance on a large filesystem with large files. Most (90%+) of my files are over 1GiB. Would there be any perceivable improvement?

Assuming there would be an improvement, what are the risks involved with installing a newer version of mdadm while it's running? Could I make a livecd with the latest version, reshape from that, then continue using once it's reshaped??

I plan to add another drive in the near future, so I'll be reshaping then and may change chunk size at that point and kill 2 birds... Again I need to fully understand the implications of upgrading mdadm vs putting it on a live cd.