Messages in this thread | | | Date | Fri, 25 Oct 2013 11:10:22 +0800 | Subject | Re: A thought about IO scheduler in linux kernel for SSD | From | 韩磊 <> |
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2013/10/23 Jan Kara <jack@suse.cz>: > On Wed 23-10-13 08:47:44, 韩磊 wrote: >> Nowadays,the IO schedulers in linux kernel have four types: >> >> deadline,noop,Anticiptory and CFQ.CFQ is the default scheduler.But CFQ is >> not a good scheduler for SSD,dealine may be a good choice. > > That doesn't make much sense to me. If there are two bios in flight for > some sector, results are undefined. Thus we usually avoid such situation > (usually we want to have defined contents of the disk :). The exclusion is > usually achieved at higher level using page locking etc. So adding code > speeding up such requests doesn't seem worth it. > > Honza > -- > Jan Kara <jack@suse.cz> > SUSE Labs, CR
Do you mean that the probability of two bios have the same start sector in request list at this level is very low??Discuss with you is a kind of enjoyment. -- 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/
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