Hi, I found that elevator=deadline performs much better than noop for writes, and almost as well for reads, and started to wonder how a combination of noop (for read) + deadline (for write) would work in practice (since deadline still doesn't support the automatic ssd detection). I developed a simple hybrid scheduler (see attached), that implements this idea, and it saved 1 s of my boot time compared to all other schedulers (cfq, deadline and noop, each loses on some part of the workload), that is a mixed read write workload, with writes that go mainly to a very slow device (SDHC card, where I mount /var). This proof of concept still doesn't support priorities, but I'm willing to add them at least for read, in which the latency for sync-reads could be improved. Corrado On Sat, Feb 7, 2009 at 6:58 PM, Jan Knutar wrote: > On Wednesday 04 February 2009, J.A. Magallón wrote: > >> Perhaps the reason is that, as the SSD is not so good, it behaves >> more like a rotational drive ;). > > Do any other SSDs except Intel's exist that DON'T behave more like a > rotational drive? I am guessing using something like LogFS would give > the biggest boost on cheap SSDs and all memory cards. > -- > 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/ > -- __________________________________________________________________________ dott. Corrado Zoccolo mailto:czoccolo@gmail.com PhD - Department of Computer Science - University of Pisa, Italy -------------------------------------------------------------------------- The self-confidence of a warrior is not the self-confidence of the average man. The average man seeks certainty in the eyes of the onlooker and calls that self-confidence. The warrior seeks impeccability in his own eyes and calls that humbleness. Tales of Power - C. Castaneda