Re: Softirq preemption

[Lee Revell <rlrevell@joe-job.com>]

On Thu, 2005-12-01 at 14:08 -0500, Lee Revell wrote:
> Ingo,
> 
> Is there any chance that the softirq preemption feature from the -rt
> kernel can be pushed upstream?
> 

FWIW, here is the longest latency I see with 2.6.14-rt22, with the same
preemption settings as 2.6.14 + PREEMPT.  AFAICT a longish network
softirq gets interrupted by several disk and network interrupts which
adds up to ~1ms.  Is there any easy way to break up this code path that
could be acceptable for mainline, or does this seem like a reasonable
lower limit on achievable latency (until/unless PREEMPT_RT gets merged
etc)?

Lee

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