gvinum raid5 performance seems slow

Petri Helenius pete at he.iki.fi
Mon Oct 30 05:11:33 UTC 2006

Greg 'groggy' Lehey wrote:
> Single stream tests aren't very good examples for RAID-5, because it
> performs writes in two steps: first it reads the old data, then it
> writes the new data.
If it really does it this way, instead doing write-only when writing 
sufficiently large blocks, that would explain the performance due to 
double rotational latency wait for each stripe size. Most 
implementations also use read/write caches to optimize this even further.


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