Re: SSD slowdown with 3.3.X?
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Mark Lord <kernel@xxxxxxxxxxxx> writes: > On 12-04-20 10:40 PM, Mark Lord wrote: >> On 12-04-19 10:07 PM, Joe Ceklosky wrote: >>> Mark, >>> >>> >>> Thanks for the info, but nothing like that shows up: >>> >>> >>> [jceklosk@neptune tmp]$ cat c-3.2.15 >>> noop deadline [cfq] >>> noop deadline [cfq] >>> >>> >>> [jceklosk@neptune tmp]$ cat c-3.3.2 >>> noop deadline [cfq] >>> noop deadline [cfq] >> >> >> Well, the stuff you posted (above) shows that cfq is being used >> instead of noop. For SSDs, noop is the more natural choice, >> and used to be the default in the kernel for a while. >> I wonder when that changed? > > Looking into the block layer now, I see that "cfq" at some point > became "SSD aware", which is probably when the default io scheduler > for SSDs changed back to cfq from noop. The block layer never changed the I/O scheduler based on whether or not the underlying storage was an SSD. Maybe your particular distro did that for you? I can't say for sure, and it really doesn't matter as the original report, here, is that the SAME CONFIGURATION (cfq old and new) now regresses in performance. We should concentrate on fixing *that*. Cheers, Jeff -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html