On 25 August 2014 10:26, Trent W. Buck <trentbuck@gmail.com> wrote:
I can't account for this unless your storage is on eMMC or similar. Have you looked for processes in D state & run iostat?
falidae# iostat Linux 3.12-0.bpo.1-amd64 (falidae) 30/08/14 _x86_64_ (8 CPU) avg-cpu: %user %nice %system %iowait %steal %idle 1.29 0.04 0.26 19.77 0.00 78.65 Device: tps kB_read/s kB_wrtn/s kB_read kB_wrtn sda 34.12 637.80 218.87 640881 219924 sdc 21.07 87.49 403.81 87910 405759 sdb 90.41 591.97 403.81 594830 405759 md0 132.01 677.53 403.67 680806 405620 dm-0 0.09 0.37 0.00 372 0 scd0 0.02 0.10 0.00 96 0 dm-1 130.91 674.30 403.66 677557 405608 dm-2 0.33 1.31 0.01 1317 12 dm-3 0.09 0.37 0.00 376 0 dm-4 0.09 0.37 0.00 372 0 dm-5 0.09 0.37 0.00 372 0 19.77% seems very high for what appeared to be a idle system running X-Windows and two idle web browsers. Any ideas on how to find what is causing it to be so high? (in the above, sda is solid state disk used by /, sdb+sdc is the underlying disk used by md0 which is raid1) Is dropping a bit now, but still high: falidae# iostat Linux 3.12-0.bpo.1-amd64 (falidae) 30/08/14 _x86_64_ (8 CPU) avg-cpu: %user %nice %system %iowait %steal %idle 1.13 0.03 0.22 14.42 0.00 84.21 Device: tps kB_read/s kB_wrtn/s kB_read kB_wrtn sda 23.96 445.45 153.82 641145 221396 sdc 15.98 61.28 291.36 88194 419357 sdb 64.40 414.07 291.36 595970 419357 md0 94.16 474.00 291.17 682230 419088 dm-0 0.06 0.26 0.00 372 0 scd0 0.02 0.07 0.00 96 0 dm-1 93.31 471.74 291.16 678981 419076 dm-2 0.23 0.92 0.01 1317 12 dm-3 0.07 0.26 0.00 376 0 dm-4 0.06 0.26 0.00 372 0 dm-5 0.06 0.26 0.00 372 0 Also considered the possibility that md0 is resyncing - that would explain everything. Unfortunately /proc/mdstat says it isn't. falidae# cat /proc/mdstat Personalities : [raid1] md0 : active raid1 sdb1[0] sdc1[1] 1953382208 blocks super 1.2 [2/2] [UU] unused devices: <none> -- Brian May <brian@microcomaustralia.com.au>