Raúl Alexis Betancor Santana wrote:
El Tuesday 18 September 2007 15:25:33 Seth Mattinen escribió:Although it seems everyone picks on hardware RAID vs. software RAID, and seems to prefer software RAID, decent hardware controllers do have generous battery backed caches software RAID can't typically match.I prefer software raid because it's a lot cheaper, "more or least" give the same performance (if you use good SAS or SATA controlers) and easier to replace/repair in case of failure.Battery backed caches does not help you in case of motherboard die or power suply switch-off, because if you use any "decent" FS over it, it will not be in sync when light goes out. Thats why newer fs support point-in-time techniques, like metadata storage, journaling, etc.
What? Stuff in cache that the controller gave the OK to the OS that it was written to disk and didn't make it to the array will be written out the next time it's powered up. If they don't do anything in power out incidents, then what do you think they do?
~Seth