On 18.03.2014 16:47, Brian Bevins wrote:
Is there any way to specify that CA delivery of updates from certain
records should be prioritized over other records on the same ioc?
I've got an application where a bunch of ai's are processed at 10Hz
and some relatively big (for us) waveforms are processed at about
0.3-0.5 Hz. The ioc is not heavily loaded and all record processing
seems to happen in a timely way, but from the client end (EDM) the
"fast" records all pause for ~0.5 sec whenever the waveforms push out
their CA updates.
The ai's are already being processed at a higher priority, but this
doesn't seem to help their updates get pushed out with higher priority.
Is there some tinkering I can do with the priorities of the CA threads
to get what I want? How can I tell which thread will get which record
updates? Is there something more obvious I'm missing?
Thanks,
--Brian
The CA thread pairs on the server (IOC) are created per client.
The client can set the priority as an argument to the
ca_create_channel() call [1].
If the client-set priorities are honored on the server depends on the
server side OS and/or configuration.
On real-time Linux, the MCoreUtils module [2] (EPICS 3.15 only) contains
a rule-based engine to tinker with IOC thread priorities and policies.
Cheers,
~Ralph
[1]
http://www.aps.anl.gov/epics/base/R3-14/12-docs/CAref.html#ca_create_channel
[2] http://epics.sourceforge.net/mcoreutils/
- Replies:
- Re: Prioritizing Channel Access per Record? Brian Bevins
- References:
- Prioritizing Channel Access per Record? Brian Bevins
- Navigate by Date:
- Prev:
Prioritizing Channel Access per Record? Brian Bevins
- Next:
NIKHEF hall probes Pierrick Hanlet
- 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:
Prioritizing Channel Access per Record? Brian Bevins
- Next:
Re: Prioritizing Channel Access per Record? Brian Bevins
- 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
|