Re: [PATCH v2 net-next] softirq: reduce latencies

2013-01-05 Thread Sedat Dilek
[ QUOTE ] From: Eric Dumazet Date: Thu, 03 Jan 2013 23:49:40 -0800 > From: Eric Dumazet > > In various network workloads, __do_softirq() latencies can be up > to 20 ms if HZ=1000, and 200 ms if HZ=100. > > This is because we iterate 10 times in the softirq dispatcher, > and some actions can con

Re: [PATCH v2 net-next] softirq: reduce latencies

2013-01-04 Thread David Miller
From: Eric Dumazet Date: Thu, 03 Jan 2013 23:49:40 -0800 > From: Eric Dumazet > > In various network workloads, __do_softirq() latencies can be up > to 20 ms if HZ=1000, and 200 ms if HZ=100. > > This is because we iterate 10 times in the softirq dispatcher, > and some actions can consume a lo

Re: [PATCH v2 net-next] softirq: reduce latencies

2013-01-04 Thread Eric Dumazet
On Fri, 2013-01-04 at 01:12 -0800, Joe Perches wrote: > On Fri, 2013-01-04 at 00:23 -0800, Eric Dumazet wrote: > > On Fri, 2013-01-04 at 00:15 -0800, Joe Perches wrote: > > > Perhaps MAX_SOFTIRQ_TIME should be > > > #define MAX_SOFTIRQ_TIME msecs_to_jiffies(2) > > > though it would be nicer if it w

Re: [PATCH v2 net-next] softirq: reduce latencies

2013-01-04 Thread Joe Perches
On Fri, 2013-01-04 at 00:23 -0800, Eric Dumazet wrote: > On Fri, 2013-01-04 at 00:15 -0800, Joe Perches wrote: > > Perhaps MAX_SOFTIRQ_TIME should be > > #define MAX_SOFTIRQ_TIME msecs_to_jiffies(2) > > though it would be nicer if it were a compile time constant. > > If you send a patch to convert

Re: [PATCH v2 net-next] softirq: reduce latencies

2013-01-04 Thread Eric Dumazet
On Fri, 2013-01-04 at 00:15 -0800, Joe Perches wrote: > On Thu, 2013-01-03 at 23:49 -0800, Eric Dumazet wrote: > > In various network workloads, __do_softirq() latencies can be up > > to 20 ms if HZ=1000, and 200 ms if HZ=100. > > This patch changes the fallback to ksoftirqd condition to : > > - A

Re: [PATCH v2 net-next] softirq: reduce latencies

2013-01-04 Thread Joe Perches
On Thu, 2013-01-03 at 23:49 -0800, Eric Dumazet wrote: > In various network workloads, __do_softirq() latencies can be up > to 20 ms if HZ=1000, and 200 ms if HZ=100. > This patch changes the fallback to ksoftirqd condition to : > - A time limit of 2 ms. [] > diff --git a/kernel/softirq.c b/kernel

[PATCH v2 net-next] softirq: reduce latencies

2013-01-03 Thread Eric Dumazet
From: Eric Dumazet In various network workloads, __do_softirq() latencies can be up to 20 ms if HZ=1000, and 200 ms if HZ=100. This is because we iterate 10 times in the softirq dispatcher, and some actions can consume a lot of cycles. This patch changes the fallback to ksoftirqd condition to :