Hi Dong-Jae, Thanks for being intersted in dm-ioband. > I tested dm-ioband( the latest release, ver 1.7.0 ) IO controller, but > I had a strange result from it. > I have something wrong in test process? > The test process and results are in attached file. > Can you check my testing result and give me a helpful advices and comments? There are some suggestions for you. 1. you have to specify a dm-ioband device at the command line to control bandwidth. # tiotest -R -d /dev/mapper/ioband1 -f 300 2. tiotest is not an appropriate tool to see how bandwith is shared among devices, becasue those three tiotests don't finish at the same time, a process which issues I/Os to a device with the highest weight finishes first, so you can't see how bandwidth is shared from the results of each tiotest. I use iostat to see the time variation of bandiwdth. The followings are the outputs of iostat just after starting three tiotests on the same setting as yours. # iostat -p dm-0 -p dm-1 -p dm-2 1 Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn dm-0 5430.00 0.00 10860.00 0 10860 dm-1 16516.00 0.00 16516.00 0 16516 dm-2 32246.00 0.00 32246.00 0 32246 avg-cpu: %user %nice %system %iowait %steal %idle 0.51 0.00 21.83 76.14 0.00 1.52 Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn dm-0 5720.00 0.00 11440.00 0 11440 dm-1 16138.00 0.00 16138.00 0 16138 dm-2 32734.00 0.00 32734.00 0 32734 ... > You can refer the testing tool, tiobench, in > http://sourceforge.net/projects/tiobench/ > Originally, tiobench don't support the direct IO mode testing, so I > added the O_DIRECT option to tiobench source code and recompile it to > test the Direct IO cases Could you give me the O_DIRECT patch? Thanks, Ryo Tsuruta -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel