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Subject: Re: remnant errlog thread
From: "Johnson, Andrew N." <anj@aps.anl.gov>
To: Al Honey <ahoney@keck.hawaii.edu>
Cc: "tech-talk@aps.anl.gov" <tech-talk@aps.anl.gov>
Date: Thu, 10 Aug 2017 23:52:07 +0000
Hi Al,

Have you tried keeping the CA context alive for the life of the persistent task? I don't see why you would want/need to repeatedly create and destroy the context, and it seems likely to me that's what is restarting the errlog thread, although I can't explain why (unless you are manually loading and unloading the libCom.so library as well). I think the CA library's IOC detection logic will work better if allowed to stay alive, as long as your network connection isn't going up and down as well.

HTH,

- Andrew

-- 
Sent from my iPad

On Aug 10, 2017, at 10:02 PM, Al Honey <ahoney@keck.hawaii.edu> wrote:

Hi

I have a persistent task, which opens and closes connections to various IOCs (other services as well) per client requests.

Seems that each open/close cycle causes another thread to be created and it never terminates – errlogThread.  I suspect there is one more step I need to perform when ‘closing’ a connection.

 

This the output from gdb for one of the remnant threads:

#0  0x00007f122a317705 in pthread_cond_wait@@GLIBC_2.3.2 ()

   from /lib64/libpthread.so.0

#1  0x00007f1227ee8099 in condWait (mutexId=0x12c6300, condId=0x12c6328)

    at ../../../src/libCom/osi/os/posix/osdEvent.c:75

#2  epicsEventWait (pevent=0x12c6300)

    at ../../../src/libCom/osi/os/posix/osdEvent.c:137

#3  0x00007f1227ed269e in errlogThread ()

    at ../../../src/libCom/error/errlog.c:491

#4  0x00007f1227ee5e6f in start_routine (arg=0x12ca420)

    at ../../../src/libCom/osi/os/posix/osdThread.c:385

#5  0x00007f122a313df5 in start_thread () from /lib64/libpthread.so.0

#6  0x00007f122950c1ad in clone () from /lib64/libc.so.6

 

Using R3.14.12.5

This is my process for opening a connection:

ca_context_create

ca_add_exception_event

ca_add_fd_registration

 

for each channel:

  ca_search_and_connect

  ca_add_masked_array_event

 

This is my process for closing a connection:

for each channel:

  ca_clear_event

  ca_clear_channel

 

ca_flush_io

ca_context_destroy

 

What did I miss?

 

Thanks for any help,

Al

 


Replies:
RE: remnant errlog thread Al Honey
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