Ubuntu's 3.2.0-27-generic. I can test on a newer kernel tomorrow. --Andy On Tue, Aug 14, 2012 at 6:07 PM, kedacomkernel <kedacomkernel@xxxxxxxxx> wrote: > On 2012-08-15 08:49 Andy Lutomirski <luto@xxxxxxxxxxxxxx> Wrote: >>If I do: >># dd if=/dev/zero of=/dev/md0p1 bs=8M >>then iostat -m 5 says: >> >>avg-cpu: %user %nice %system %iowait %steal %idle >> 0.00 0.00 26.88 35.27 0.00 37.85 >> >>Device: tps MB_read/s MB_wrtn/s MB_read MB_wrtn >>sdb 265.20 1.16 54.79 5 273 >>sdc 266.20 1.47 54.73 7 273 >>sdd 264.20 1.38 54.54 6 272 >>sdf 286.00 1.84 54.74 9 273 >>sde 266.60 1.04 54.75 5 273 >>sdg 265.00 1.02 54.74 5 273 >>md0 55808.00 0.00 218.00 0 1090 >> >>If I do: >># dd if=/dev/zero of=/dev/md0p1 bs=8M oflag=direct >>then iostat -m 5 says: >>avg-cpu: %user %nice %system %iowait %steal %idle >> 0.00 0.00 11.70 12.94 0.00 75.36 >> >>Device: tps MB_read/s MB_wrtn/s MB_read MB_wrtn >>sdb 831.00 8.58 30.42 42 152 >>sdc 832.80 8.05 29.99 40 149 >>sdd 832.00 9.10 29.78 45 148 >>sdf 838.40 9.11 29.72 45 148 >>sde 828.80 7.91 29.79 39 148 >>sdg 850.80 8.00 30.18 40 150 >>md0 1012.60 0.00 101.27 0 506 >> >>It looks like md isn't recognizing that I'm writing whole stripes when >>I'm in O_DIRECT mode. >> > kernel version? > >>--Andy >> >>-- >>Andy Lutomirski >>AMA Capital Management, LLC >>-- >>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 -- Andy Lutomirski AMA Capital Management, LLC -- 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
