Messages in this thread | | | Date | Tue, 29 Mar 2005 12:19:47 +0200 | From | Jens Axboe <> | Subject | Re: [patch] use cheaper elv_queue_empty when unplug a device |
| |
On Tue, Mar 29 2005, Arjan van de Ven wrote: > On Tue, 2005-03-29 at 19:19 +1000, Nick Piggin wrote: > > - removes the relock/retry merge mechanism in __make_request if we > > aren't able to get the GFP_ATOMIC allocation. Just fall through > > and assume the chances of getting a merge will be small (is this > > a valid assumption? Should measure it I guess). > > this may have a potential problem; if the vm gets in trouble, you > suddenly start to generate worse IO patterns, which means IO performance > goes down right when it's most needed..... > > of course we need to figure if this actually ever hits in practice, > because if it doesn't I'm all for simpler code.
Precisely, see my response as well. If the noretry flag works, that should be fine.
-- Jens Axboe
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |