odd problem(s) with libthr and libkse

[David Xu]

Christopher M. Sedore wrote:

>I have a multithreaded program that I've built to run under libc_r, libthr, and libkse.  I use the libc_r build for debugging and the others for actual work (the program is disk/network io intensive and I want the disk io concurrency from thr or kse).
> 
>Anyway, here is the issue I'm seeing.  It may be the same or a related problem for both, or may not be.
> 
>When running under libthr, everything works fine for an indeterminate period, usually between 10 seconds and 30 minutes.  Eventually, all program function stops.  If I watch in top, threads get stuck in "sigwai".  First one, then a couple, then all.  
> 
>When running under kse, the program pauses periodically.  I have one thread that prints out a heartbeat once per second, and prints debug info.  I get pauses of up to 5 seconds between my heartbeat:
> 
>8 per sec (40/5) - 3739 total, 6047 pce active
>6 per sec (32/5) - 3722 total
>timer 1065864344
>timer 1065864347
>timer 1065864348
>7 per sec (38/5) - 3777 total, 6034 pce active
>7 per sec (39/5) - 3761 total
>timer 1065864350
>timer 1065864351
>accepted on 14
>accepted on 15
>timer 1065864353
>4 per sec (20/5) - 3797 total, 6058 pce active
>6 per sec (30/5) - 3791 total
>timer 1065864354
>timer 1065864355
>timer 1065864357
>
>(note skips from 1065864348 to 350, 351 to 353, 355 to 357)
> 
>When the pauses occur, network traffic dips to nearly nothing:  Overall program performance with libkse is about 25-50% of what it is under libthr (when working) or ~30-60% of libc_r.
> 
>I have no problems when running under libc_r.  Any suggestions to debug this?
> 
>I'm running 5.1-CURRENT-20030917-JPSNAP.
>  
>
Can you tell me how many threads in your process ?
Make sure you didn't hit the hard limits in kernel :

#sysctl -a |grep kern.threads
kern.threads.debug: 0
kern.threads.max_threads_per_proc: 150
kern.threads.max_groups_per_proc: 50
kern.threads.max_threads_hits: 0
kern.threads.virtual_cpu: 1

> 
>Thanks,
> 
>-Chris
> 
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>  
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