Messages in this thread | | | Date | Tue, 14 Oct 2008 10:54:25 +0200 | From | Pierre Ossman <> | Subject | Re: QUEUE_FLAG_NONROT and merges |
| |
On Tue, 14 Oct 2008 09:54:08 +0200 Jens Axboe <jens.axboe@oracle.com> wrote:
> On Tue, Oct 14 2008, Pierre Ossman wrote: > > Hi Jeff, > > > > I noticed you've added a new flag to indicate that the drive has no > > seek costs and I figured it would be a good idea to use that on the > > MMC/SD cards. > > That was me, actually... >
Sorry, this was meant for you of course. I don't know how I got things mixed up there. I guess I'll have to blame lack of coffee this morning. :)
> > Since the name isn't entirely clear in what is implied, I just wanted > > to check that there are no plans to assume that there is negligable > > request overhead for queues with this flag. I.e. the flag should > > indicate that the elevator doesn't have to care about seeks, but it > > should still try to merge requests to reduce the transaction overhead. > > Sounds about right. The flag is just meant to indicate zero-seek cost, > as devices will still have per-command overheads, merging is still > applicable. > > So yes, you want to set that flag for mmc/sd cards, definitely. >
Great. I'll get a patch out ASAP.
Rgds -- -- Pierre Ossman
Linux kernel, MMC maintainer http://www.kernel.org rdesktop, core developer http://www.rdesktop.org
WARNING: This correspondence is being monitored by the Swedish government. Make sure your server uses encryption for SMTP traffic and consider using PGP for end-to-end encryption. [unhandled content-type:application/pgp-signature] | |