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Re: DIOC{G,S}STRATEGY not implemented for all disk devices

On Wed, Jan 16, 2008 at 10:19:28AM +0200, Alan Barrett wrote:
> Why don't the DIOC{G,S}STRATEGY ioctls work for all disk devices?

Perhaps because they are not needed any more - back in the old days
when disk devices were dumber doing clever ordering on the host
allowed you to optimise the disk access but in these days of large on
disk caches and tagged queuing the order in which the commands are
submitted to the disk may not be the order in which they are executed
by the disk device so there is little point in doing any strategising
on the host side (I think)

Brett Lymn
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