Vivek Goyal wrote: > On Mon, Jul 27, 2009 at 10:10:34AM +0800, Gui Jianfeng wrote: >> Hi， >> >> Here are some fio test results for IO Controller V6 built and not built. >> Iozone test results are also attached. >> > > Hi Gui, > > Thanks a lot for some performance numbers. It seems to be a mixed chart. > Performance gains at some places and loss at others. I am curious about > that -7.0% for normal writes. Not sure what can contribute to that. > > What was the value of "fairness" parameter when you ran those tests? Can you > please set fairness = 0 and re-run the tests (if you have already not done so). > > By default fairness is set to 1 in V6. With fairness = 0, we should be very > close to existing CFQ behavior. If not, then we need to dive deeper and > see why variations are happening. Hi Vivek, I re-run the fio test under V6 for normal reads and writes with fairness == 0. It seems the performance gets a little better for normal writes than before. Mode Normal read | Random read | Normal write | Random write 2.6.31-rc1 53,547KiB/s 2,894KiB/s 44,088KiB/s 8,450KiB/s V6(fairness = 0) 53,199KiB/s 2,847KiB/s 41,898KiB/s 8,582KiB/s Performance 0% -1.6% -4.9% +1.5% > > Is it also possible to run the same tests with V7. > > Thanks > Vivek > >> Arch: X86 >> Mem: 1G >> Disk: 320G >> IO Scheduler: CFQ >> >> ============ >> By normal read and write syscall. >> >> Block Size:32K >> File Size: 1G * 10 >> >> Mode Normal read | Random read | Normal write | Random write | Direct read | Direct write >> >> 2.6.31-rc1 47,932KiB/s 3,566KiB/s 45,693KiB/s 8,501KiB/s 50,088KiB/s 43,473KiB/s >> >> 2.6.31-rc1-Vivek-V6 47,231KiB/s 3,411KiB/s 42,451KiB/s 8,714KiB/s 51,284KiB/s 42,341KiB/s >> >> Performance -1.5% -4.4% -7.0% +2.5% +2.4% -2.6% >> >> ============ >> >> By mmap. >> >> Block Size:32K >> File Size: 500M >> >> Mode Normal read | Random read | Normal write | Random write >> >> 2.6.31-rc1 49,951KiB/s 3,245KiB/s 21,950KiB/s 2,771KiB/s >> >> 2.6.31-rc1-Vivek-V6 49,951KiB/s 3,154KiB/s 22,593KiB/s 2,648KiB/s >> >> Performance 0% -2.8% +2.9% -4.4% >> >> ============ >> >> By libaio calls >> >> Block Size:32K >> File Size: 500M >> >> Mode Normal read | Random read | Normal write | Random write >> >> 2.6.31-rc1 49,447KiB/s 3,296KiB/s 57,519KiB/s 21,093KiB/s >> >> 2.6.31-rc1-Vivek-V6 50,142KiB/s 3,238KiB/s 57,791KiB/s 21,283KiB/s >> >> Performance +1.4% -1.8% 0% +0.1% >> >> ============ >> >> >> >> >> >> >> >> >> >> >> > > > > > > -- Regards Gui Jianfeng -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
