* Merlin Moncure <mmoncure@gmail.com> [090831 10:38]:
> I agree, that's good analysis. The main point I was making was that
> if you have say a 10 disk raid 5, you don't involve 10 disks, only
> two...a very common misconception. I made another mistake that you
> didn't catch: you need to read *both* the data drive and the parity
> drive before writing, not just the parity drive.
>
> I wonder if flash SSD are a better fit for raid 5 since the reads are
> much cheaper than writes and there is no rotational latency. (also,
> $/gb is different, and so are the failure cases).
The other thing that scares me about raid-5 is the write-hole, and the
possible delayed inconsistency that brings...
Again, hopefully mitigated by a dependable controller w/ BBU...
--
Aidan Van Dyk Create like a god,
aidan@highrise.ca command like a king,
http://www.highrise.ca/ work like a slave.
