W liście z pon, 17-01-2005, godz. 16:51, Hans Kristian Rosbach pisze: [...] > Actually I have managed to get about 30-40% higher throughput with just > a little hacking on the code that selects what disk to use. > > Problem is > -It selects the disk that is closest to the wanted sector by remembering > what sector was last requested and what disk was used for it. > -For sequential reads (sucha as hdparm) it will override and use the > same disk anyways. (sector = lastsector+1) > > I gained a lot of throughput by alternating disk, but seek time was > roughly doubled. I also tried to get smart and played some with the > code in order to avoid seeking both disks back and forth wildly when > there were two sequential reads. I didn't find a good way to do it > unfortunately. What about the special case where whole disks are mirrored? Then there is no need for selecting disks other than round-robin, because the heads should be in similar positions (except for rebuild situation). I will be more than happy to give up partitions to get better performance instead. I have two disks, so raid 1+0 is not an option. Could you please reconsider releasing your patch? Best regards, Janusz - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
