EPICS Home EPICS Controls Argonne National Laboratory

Experimental Physics and
Industrial Control System

Format page
for printing


Search Tech-talk
1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  2017  2018  2019  <2020>  2021  2022  2023  2024  Index 1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  2017  2018  2019  <2020>  2021  2022  2023  2024 
<== Date ==> <== Thread ==>
Subject: Re: Question about two minor issues with IOCs
From: Ralph Lange via Tech-talk <[email protected]>
To: EPICS Tech Talk <[email protected]>
Date: Fri, 17 Jan 2020 05:43:20 +0100
In general,

all "I/O Intr" records may end up in the callback queue, and asynchronously processed records with PINI=YES will be in the scanOnce queue first, then (for the second phase processing) in the callback queue. Batched processing of asynchronous records (e.g. many records in one SCAN phase) may put the whole batch in the callback queue at once - depending on your Device Support. Callback queues are by priority, so spreading the record priorities will change the load. Using multiple parallel (concurrent) callback threads on multi-core IOCs gets the queues emptied faster. 

For some of ITER's conventional systems IOCs (connecting to large PLCs with >100k interfaced signals) we are using queue sizes well over 100k. Fine on Linux, where this is "just" memory.
Failing to find a formula that would come up with a good queue size for any specific IOC, we now tell users to just gradually increase the queue size until they don't get overflow messages anymore.

Cheers,
~Ralph


On Thu, 16 Jan 2020 at 21:25, Mark Rivers via Tech-talk <[email protected]> wrote:

Ø  I think that this is in fact a better solution. That way when adding plugins this number can be adjusted if necessary.

 

I have added callbackSetQueueSize(5000) to EXAMPLE_commonPlugins.cmd and pushed to the master branch on Github.

References:
Question about two minor issues with IOCs Wlodek, Jakub via Tech-talk
RE: Question about two minor issues with IOCs Mark Rivers via Tech-talk
Re: Question about two minor issues with IOCs Wlodek, Jakub via Tech-talk
RE: Question about two minor issues with IOCs Mark Rivers via Tech-talk
Re: Question about two minor issues with IOCs Wlodek, Jakub via Tech-talk
RE: Question about two minor issues with IOCs Mark Rivers via Tech-talk
Re: Question about two minor issues with IOCs Wlodek, Jakub via Tech-talk
RE: Question about two minor issues with IOCs Mark Rivers via Tech-talk
Navigate by Date:
Prev: RE: areaDetector/ADEiger question Mark Rivers via Tech-talk
Next: Probelm with ethernet interface of Galil controller wangqisheng--- via Tech-talk
Index: 1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  2017  2018  2019  <2020>  2021  2022  2023  2024 
Navigate by Thread:
Prev: RE: Question about two minor issues with IOCs Mark Rivers via Tech-talk
Next: RE: Question about two minor issues with IOCs Mark Rivers via Tech-talk
Index: 1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  2017  2018  2019  <2020>  2021  2022  2023  2024 
ANJ, 17 Jan 2020 Valid HTML 4.01! · Home · News · About · Base · Modules · Extensions · Distributions · Download ·
· Search · EPICS V4 · IRMIS · Talk · Bugs · Documents · Links · Licensing ·