Re: Are large RAID stripe sizes useful with FreeBSD?

Ivan Voras wrote:
Most of new hardware RAID controllers offer stripe sizes of 128K, 256K
and some also have 512K and 1M stripes. In the simplest case of RAID0 of
two drives, knowing that the data is striped across the drives and that
FreeBSD issues IO request of at most 64K, is it useful to set stripe
sizes to anything larger than 32K? I suppose something like TCQ would
help the situation but does anyone know how is this situation usually
handled on the RAID controllers?

Short answer: yes. Larger stripe sizes would allow better performance for continuous read/write. In theory they will negatively affect small size read/write but in practice you will notice that larger stripe size would give better performance in almost all cases.

--
Xin LI <delphij@xxxxxxxxxxx> http://www.delphij.net/
FreeBSD - The Power to Serve!
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