4 Apr
2000
4 Apr
'00
4:58 p.m.
"Brian" == Brian Tao taob@risc.org writes:
Brian> I thought at least the parity calculations in a Netapp were Brian> offloaded to an ASIC, so it doesn't tie up the Brian> general-purpose CPU with trivial calculations?
Rebuilding in raid-4/5 isn't expensive due to the parity calculations. After all, the XOR operations takes few cycles on most CPU's. It the reading of the blocks from each disk and then the resulting write back to the rebuilding disk that are the expensive part of rebuilding under raid 4/5.
j.