On 27/10/12 11:56 AM, Ray Arachelian wrote:
On 10/26/2012 04:29 AM, Karl Wagner wrote:
Does it not store a separate checksum for a parity block? If so, it
should not even need to recalculate the parity: assuming checksums
match for all data and parity blocks, the data is good.
Parity is very simple to calculate and doesn't use a lot of CPU - just
slightly more work than reading all the blocks: read all the stripe
blocks on all the drives involved in a stripe, then do a simple XOR
operation across all the data. The actual checksums are more expensive
as they're MD5 - much nicer when these can be hardware accelerated.
Checksums are MD5??
Also, on x86, ...
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