Messages in this thread | | | Subject | Re: [RFC PATCH] kick ksoftirqd more often to please soft lockup detector | From | Peter Zijlstra <> | Date | Wed, 29 Feb 2012 10:17:03 +0100 |
| |
On Tue, 2012-02-28 at 14:16 -0800, Dan Williams wrote: > Looks like everyone is guilty: > > [ 422.765336] softirq took longer than 1/4 tick: 3 NET_RX ffffffff813f0aa0 > ... > [ 423.971878] softirq took longer than 1/4 tick: 4 BLOCK ffffffff812519c8 > [ 423.985093] softirq took longer than 1/4 tick: 6 TASKLET ffffffff8103422e > [ 423.993157] softirq took longer than 1/4 tick: 7 SCHED ffffffff8105e2e1 > [ 424.001018] softirq took longer than 1/4 tick: 9 RCU ffffffff810a0fed > [ 424.008691] softirq loop took longer than 1/2 tick need_resched:
/me kicks himself for not printing the actual duration.. :-)
> As expected whenever that 1/2 tick message gets emitted the softirq > handler is almost running in a need_resched() context.
Yeah.. that's quite expected.
> So is it a good idea to get more aggressive about scheduling ksoftrrqd?
Nah, moving away from softirq more like. I'll put moving the load-balancer into a kthread on the todo list. And it looks like everybody else should move to kthreads too.
| |