Implement THREAD_PRIORITY_TIME_CRITICAL

[Con Kolivas]

On Wednesday 05 April 2006 21:47, Aneurin Price wrote:
> Con Kolivas wrote:
> > Is it kernel dependant? Does 2.6.11 for example exhibit the problem or
> > only recent kernels? Or has noone tried an older kernel like that?

> Just to reiterate since everybody seems to forget this part: The problem
> does *not* occur when using a 2.4 kernel.

Oh I'm quite aware of that. I remember a lot of wine spinoffs refused to 
support 2.6 for 2 years  or so. Threading in 2.6 is much more sensitive.

> Additionally, I seem to recall 
> that when I tried compiling a 2.6 kernel without ALSA support (so OSS is
> native and not emulated), the problem went away even with the 2.6 kernel
> (this was back around 2.6.11ish time), though I may have misremembered
> that.

Well that's why I suggested about then. It's not alsa vs oss, but changes in 
the pipe code at about that time changed how tasks waiting on pipes were 
scheduled due to code by Linus and Ingo. Hence why I'm suggesting testing 
2.6.17-rc1 because I noted this could cause scheduling problems and modified 
the code recently to fix this and it was pushed into 2.6.17-rc1. This should 
cause an improvement in latency with any tasks that wait on pipes.

Cheers,
Con