On Fri, Mar 2, 2012 at 10:45, Ted Ts'o <tytso@xxxxxxx> wrote: > Hmm, it sounds like we're hitting some kind of scaling problem. How > many CPU's/cores do you have on your server? And it would be > interesting to try varying the --numjobs parameter and see how the > various file systems behave with 1, 2, 4, 8, and 16 threads. > I did various benchmarks with 1, 2, 4, 8, 16 and 32 threads, here are the results: http://blog.xupeng.me/misc/4-15krpm-sas-raid10/ > The other thing that's worth checking is to try using filefrag -v on > the test file after the benchmark has finished, just to make sure the > file layout is sane. It should be, but I just want to double check... Output of `filefrag -v` after the benchmark has finished: # filefrag -v /mnt/ext4/test Filesystem type is: ef53 File size of /mnt/ext4/test is 5368709120 (1310720 blocks, blocksize 4096) ext logical physical expected length flags 0 0 2424832 32758 1 32758 2457600 2457590 32758 2 65516 2490368 2490358 32758 3 98274 2523136 2523126 32758 4 131032 2555904 2555894 32758 5 163790 2588672 2588662 32758 6 196548 2719744 2621430 32758 7 229306 2752512 2752502 32758 8 262064 2785280 2785270 32758 9 294822 2818048 2818038 32758 10 327580 2850816 2850806 32758 11 360338 2883584 2883574 32758 12 393096 2916352 2916342 32758 13 425854 2949120 2949110 32758 14 458612 2981888 2981878 32758 15 491370 3014656 3014646 32758 16 524128 3047424 3047414 32758 17 556886 3080192 3080182 32758 18 589644 3112960 3112950 32758 19 622402 3178496 3145718 32758 20 655160 3211264 3211254 32758 21 687918 3244032 3244022 32758 22 720676 3276800 3276790 32758 23 753434 3309568 3309558 32758 24 786192 3342336 3342326 32758 25 818950 3375104 3375094 32758 26 851708 3407872 3407862 32758 27 884466 3440640 3440630 32758 28 917224 3473408 3473398 32758 29 949982 3506176 3506166 32758 30 982740 3538944 3538934 32758 31 1015498 3571712 3571702 32758 32 1048256 3604480 3604470 32758 33 1081014 3637248 3637238 32758 34 1113772 3702784 3670006 32758 35 1146530 3735552 3735542 32758 36 1179288 3768320 3768310 32758 37 1212046 3801088 3801078 32758 38 1244804 3833856 3833846 32758 39 1277562 3866624 3866614 32758 40 1310320 3899392 3899382 400 eof /mnt/ext4/test: 41 extents found -- Xupeng Yun http://about.me/xupeng -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
