On Thu, 24 May 2012, Edgar Fuß wrote:
I then build a RAID 1 with SectorsPerSU=128 (e.g. a 64k stripe size) on two of these discs, and, after the parity initialisation was complete, wrote to [r]raid0b. On the raw device, throghput ranged from 4MByte/s to 97MByte/s depending on bs. On the block device, it was always 3MByte/s. Furthermore, dd's WCHAN was "vnode" for the whole run. Why is that so and why is throughput so low?
What is the partition alignment on the raid?There's a discussion of the alignment impact on my raidframe how-to on the NetBSD WiKi.
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