Are large RAID stripe sizes useful with FreeBSD?
ivoras at freebsd.org
Mon Mar 31 15:18:32 PDT 2008
On 01/04/2008, Scott Long <scottl at samsco.org> wrote:
> If you have a RAID controller in front of the disks then the effects of
> TCQ are hidden from the OS; it might ultimately make the controller
> complete requests faster, but the controller already looks to the OS
> like a disk with a really deep queue. When you're dealing directly with
> the disks then TCQ/NCQ is required in order for batching of concurrent
> requests to occur.
Thanks. I thought TCQ is also used between the OS and the controller
(since the RAID array is presented to the OS as opaque...).
More information about the freebsd-current