I would add that there are effective capacity differences between the different RAID levels. For example, for N disks of K size:
RAID5: total capacity = (N-1)*K RAID6: total capacity = (N-2)*K RAID10: total capacity = N*K/2 Depending on your application, it's possible that, like you say "Disk is cheap", and that's enough to minimize the impact of capacity issue for the OP. But I think it's wise to present all the details, and let him decide what's important for the application, budget, etc. I certainly like it when vendor reps, etc., do that for me. Lloyd Brown Systems Administrator Fulton Supercomputing Lab Brigham Young University http://marylou.byu.edu On 06/23/2012 10:27 AM, Nicholas Leippe wrote: > Raid6: > - can withstand any combination of double disk fault > - much worse healthy write performance than 1+0 > - huge performance penalty in degraded and rebuild mode > > Raid1+0: > - can only withstand specific combinations of double disk fault (must > not be two pairs of the same mirror) > - minimal healthy write performance penalty > - performance hardly affected in degraded mode, rebuild mode is a > simple copy--no CPU calculations, just I/O /* PLUG: http://plug.org, #utah on irc.freenode.net Unsubscribe: http://plug.org/mailman/options/plug Don't fear the penguin. */
