sync_supers causing high cpu load - Raspberry Pi Forums

hi,

topic says, i'm having issues kernel process 'sync_supers' causing high cpu loads on long periods of time. @ times, i've caught using beyond 97% of cpu. i've read it's writing disk, wouldn't expect use cpu long periods of time. because of information, i've tried let run, see if take longer few minutes, stopped after 2 hours. way rid of high cpu load kill process. although launch later after unknown time period.

stop process killing pi appreciated.

have rev2 pi running dist-upgraded raspbian january kernel 3.12.22+

i having hard time this. seems crop when raspberry pi attached usb hard disk ext4 partition, , several instances of sync_supers. read has writing disk. it's functioning home media server , running minidlna, samba, openssh, , apache. here's showing in top:

top - 20:58:06 14 days, 2:37, 1 user, load average: 13.83, 14.32, 14.21
tasks: 105 total, 14 running, 91 sleeping, 0 stopped, 0 zombie
%cpu(s): 87.1 us, 11.0 sy, 0.0 ni, 0.0 id, 0.0 wa, 0.0 hi, 1.8 si, 0.0 st
kib mem: 496948 total, 485804 used, 11144 free, 58008 buffers
kib swap: 0 total, 0 used, 0 free, 329256 cached

pid user pr ni virt res shr s %cpu %mem time+ command
22114 pi 20 0 7444 2600 1092 r 7.7 0.5 156:01.93 [sync_supers]
22117 pi 20 0 7444 2600 1092 r 7.7 0.5 155:54.64 [sync_supers]
22981 pi 20 0 7444 2592 1084 r 7.7 0.5 2683:26 [sync_supers]
23347 pi 20 0 7444 2600 1092 r 7.7 0.5 1296:16 [sync_supers]
24202 pi 20 0 7444 2600 1092 r 7.7 0.5 140:15.80 [sync_supers]
13965 pi 20 0 7444 2600 1092 r 7.4 0.5 1307:06 [sync_supers]
22116 pi 20 0 7444 2600 1092 r 7.4 0.5 155:17.16 [sync_supers]
22138 pi 20 0 7444 2424 916 r 7.4 0.5 155:45.92 [sync_supers]
22496 pi 20 0 7444 2600 1092 r 7.4 0.5 153:39.26 [sync_supers]
5705 pi 20 0 7444 2604 1096 r 7.1 0.5 782:14.65 [sync_supers]
10810 pi 20 0 7444 2592 1084 r 7.1 0.5 3140:12 [sync_supers]
14164 guy 20 0 13080 4916 1088 r 4.4 1.0 2:32.59 sshd
10809 pi 20 0 7444 2628 1108 r 2.9 0.5 7938:32 [sync_supers]
20778 root 20 0 5272 1440 976 r 0.9 0.3 0:03.87 top
3 root 20 0 0 0 0 s 0.3 0.0 7:47.66 ksoftirqd/0
7 root 20 0 0 0 0 s 0.3 0.0 13:12.16 rcu_preempt
22477 pi 20 0 4792 1260 1096 s 0.3 0.3 0:00.01 su
1 root 20 0 2148 632 528 s 0.0 0.1 0:33.11 init
2 root 20 0 0 0 0 s 0.0 0.0 0:00.02 kthreadd
5 root 0 -20 0 0 0 s 0.0 0.0 0:00.00 kworker/0:0h
8 root 20 0 0 0 0 s 0.0 0.0 0:00.00 rcu_bh
9 root 20 0 0 0 0 s 0.0 0.0 0:00.00 rcu_sched
10 root 0 -20 0 0 0 s 0.0 0.0 0:00.00 khelper
11 root 20 0 0 0 0 s 0.0 0.0 0:00.00 kdevtmpfs
12 root 0 -20 0 0 0 s 0.0 0.0 0:00.00 netns
14 root 0 -20 0 0 0 s 0.0 0.0 0:00.00 writeback
15 root 0 -20 0 0 0 s 0.0 0.0 0:00.00 bioset
16 root 0 -20 0 0 0 s 0.0 0.0 0:00.00 kblockd
17 root 20 0 0 0 0 s 0.0 0.0 0:00.28 khubd


can kill these processes or reboot pi , we're while... know causing or can alleviate it, kill pi's performance. ideas?

thanks!

raspberrypi