Massive number of context switches on ksoftirqd
- by Pace
We have two servers that are grinding to a halt. One is a VM and the other is bare metal. Neither of them are running similar code but they are on the same network. It appears that an incredible number of context switches are arising from ksoftirqd (which is taking up a lot of CPU).
vmstat output
procs -----------memory---------- ---swap-- -----io---- -system-- -----cpu------
r b swpd free buff cache si so bi bo in cs us sy id wa st
1 0 0 605092 182496 2637556 0 0 0 0 4177 519187 8 19 73 0 0
2 0 0 605092 182496 2637556 0 0 0 0 4792 520980 8 19 74 0 0
3 0 0 605092 182496 2637552 0 0 0 0 2137 659640 18 26 56 0 0
...
pidstat output
TCK4-BM-06A:~ # pidstat -w -I 5
Linux 2.6.32.12-0.7-default (TCK4-BM-06A) 07/02/2012 _x86_64_
03:03:01 PM PID cswch/s nvcswch/s Command
03:03:06 PM 1 0.20 0.00 init
03:03:06 PM 4 386666.27 0.00 ksoftirqd/0
03:03:06 PM 6 0.60 0.00 ksoftirqd/1
03:03:06 PM 8 378213.17 0.00 ksoftirqd/2
03:03:06 PM 10 0.20 0.00 ksoftirqd/3
03:03:06 PM 12 0.20 0.00 ksoftirqd/4
03:03:06 PM 26 377115.37 0.00 ksoftirqd/11
03:03:06 PM 27 1.80 0.00 events/0
03:03:06 PM 28 1.00 0.00 events/1
03:03:06 PM 29 1.00 0.00 events/2
03:03:06 PM 30 1.00 0.00 events/3
03:03:06 PM 31 0.80 0.00 events/4
03:03:06 PM 32 0.80 0.00 events/5
...
My initial thought is that, since both are on the same network, something is flooding the network. Is this consistent with the data?
