On Sun, Jun 24, 2012 at 09:53:22PM -0400, Mikulas Patocka wrote: > So the conclusion is that is that that divide instruction degrades > transfer speed, especially on dm-stripe with 4k stripe size (on dm-thin it > is measurable only with raw read, the difference is smaller because it has > a minimum chunk size 64k). > > > The question is why do you want to avoid such optimization? You've conviced me. I just wanted proof, which you've done very nicely. Thankyou. > BTW. when unloading the dm-thin device with debugging enabled (the tests > were done with debugging disabled), I got this message: > device-mapper: space map checker: free block counts differ, checker > 131060, sm-disk:130991 > --- so there is supposedly some bug? The kernel is 3.4.3. That message is ok. I'm going to remove the sm-checker in 3.6. It's not earning it's keep. - Joe -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
