Re: [PATCH] O17int

[mru@users.sourceforge.net (Måns Rullgård)]

Con Kolivas <kernel@kolivas.org> writes:

>> When compiling from xemacs, everything is fine until the compilation
>> is done.  Then xemacs starts spinning wildly in some loop doing this:
>> This goes on for anything from half a second to several seconds.
>> During that time other processes, except X, are starved.
>>
>> I saw this first with 2.6.0-test1 vanilla, then it went away in -test2
>> and -test3, only to show up again with O16.3int.  My O16.2 kernel
>> seems ok, which seems strange to me since the difference from O16.2 to
>> O16.3 is very small.
>
> While being a small patch, 16.2-16.3 was a large change. It removed the very 
> aggressive starvation avoidance of spin on wait waker/wakee in 16.2, which 
> clearly helped your issue.

I have confirmed that this change introduced the problem.

>> Any ideas?
>
> Pretty sure we have another spinner. A reniced -11 batch run of top -d 1 and 
> vmstat during the spinning, and a kernel profile for that time will be 
> helpful.

I'll try to get that.

-- 
Måns Rullgård
mru@users.sf.net