Converting from RAID5 to RAID6

[zoltank]

I have a RAID5 array with eleven 2GB 7.2K SAS drives. After doing some research on RAID punctures and the chances of a URE during a rebuild, I did some math, and if I lose a drive and have to rebuild the array there is a decent chance I'll hit a URE and lose the entire array. That would be a bad day.

I have a global hotspare already in the server, so it would be very easy for me to convert from RAID5 to RAID6. I know I'll be taking a performance hit doing that, but how much of a real world change would I see?

[NightBird]

Raid 5 write penalty 4
Raid 6 write penalty 6

[dellock6]

You can also use this nice calculator to see some comparisons:
http://www.wmarow.com/strcalc/