Re: Noticable Delays Since Beta 3

On Fri, 2004-10-08 at 09:18 +0930, Benjamin Close wrote:
> I believe the issue is with the scheduler or something related to it. 
> The effect seems to occur when a process
>  hasn't been used for a long time and then is suddenly switched from a 
> wait state to an active state.
> One place I notice it is if I su then perform some function, leave the 
> process su'd say overnight then the next morning type exit on it.
> The 'exit' takes a while to display then once it does, it takes 3-4 
> seconds before the previous shell's prompt reappears.
> The box is never in swap with it's stats being:
> 
> Mem: 133M Active, 236M Inact, 92M Wired, 15M Cache, 60M Buf, 18M Free
> Swap: 512M Total, 512M Free
> 
> However, it has a number of constantly running processes (graphical 
> memory watches, xfishtanks, graphical load watches, etc)
> 
> Once the process responds it runs fine until the next long delay. It 
> seems more responsive with BETA7 but no where near the same as before 
> the scheduler change.
> It might be a symptom related to X, will test overnight in console.
> 
> Cheers,
>     Benjamin
> 

I have to "me too" this. I have only seen the problem with unused gettys
and bashes on vtys and in xterm. I typically do have a reasonable amount
of stuff paged out, but the delays I see aren't consistent with lots of
paging in. The system can be idle with no disk activity and I can still
see ~4 sec delays.

I have tried to get a ddb trace on a frozen process with no luck so far
- all I ever end up with is 'Thread xxx not found'. I initially assumed
this might be because part of the process was paged out - I am unsure,
though.

Sam.