Argonne National Laboratory

Experimental Physics and
Industrial Control System

1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014  2015  2016  <2017 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
<== Date ==> <== Thread ==>

Subject: Re: Archiver Appliance established multiple CA connections for one channel
From: Michael Davidsaver <mdavidsaver@gmail.com>
To: "Wang, Lin" <wanglin@ihep.ac.cn>, tech-talk@aps.anl.gov
Date: Thu, 13 Apr 2017 17:54:55 -0400
On 04/11/2017 07:55 AM, Wang, Lin wrote:
> 
> Dear all,
> 
> I deployed Archiver Appliance using install_scripts/single_machine_install.sh in our test environment, however, we found that AA established multiple CA connections for 1 channel. Is it the normal behavior for AA or something went wrong in my environment? We care this because our IOCs are running on embedded systems which have limited CPU and memory resources.

The short answer is that this is a the intended behavior.  It surprised
me the first time I noticed as well.  I believe that SLAC likes to run a
cagateway in front of AA.  Murali also mentioned that there was a
configuration option to control this (defaults to 10).  Unfortunately I
can't find that option name.



> The following is the detailed information:
> 
> One of the IOCs has 366 channels to be archived (now by both Channel Archiver and AA). When AA just started, the total archived channels equaled total channels casr() displayed, which means 1 archived channel corresponds to 1 channel casr() displays, which is straightforward.
> 
> epics> casr
> Channel Access Server V4.13
> Connected circuits:
> TCP 10.1.204.12:49088(carchiver): User="histdata", V4.11, 366 Channels, Priority=20  (This line is for Channel Archiver)
> TCP 10.1.204.41:41089(archappl): User="control", V4.13, 37 Channels, Priority=0
> TCP 10.1.204.41:41090(archappl): User="control", V4.13, 24 Channels, Priority=0
> TCP 10.1.204.41:41092(archappl): User="control", V4.13, 30 Channels, Priority=0
> TCP 10.1.204.41:41094(archappl): User="control", V4.13, 38 Channels, Priority=0
> TCP 10.1.204.41:41096(archappl): User="control", V4.13, 47 Channels, Priority=0
> TCP 10.1.204.41:41097(archappl): User="control", V4.13, 37 Channels, Priority=0
> TCP 10.1.204.41:41099(archappl): User="control", V4.13, 43 Channels, Priority=0
> TCP 10.1.204.41:41103(archappl): User="control", V4.13, 38 Channels, Priority=0
> TCP 10.1.204.41:41105(archappl): User="control", V4.13, 38 Channels, Priority=0
> TCP 10.1.204.41:41106(archappl): User="control", V4.13, 34 Channels, Priority=0
> 
> However, after several hours, casr() output changed as follows, the total channels casr() displayed became multiple times of total archived channels, which means 1 archived channel corresponds to multiple channels casr() displays.
> 
> epics> casr
> Channel Access Server V4.13
> Connected circuits:
> TCP 10.1.204.12:49088(carchiver): User="histdata", V4.11, 366 Channels, Priority=20  (This line is for Channel Archiver)
> TCP 10.1.204.41:39671(archappl): User="control", V4.13, 216 Channels, Priority=0
> TCP 10.1.204.41:39672(archappl): User="control", V4.13, 192 Channels, Priority=0
> TCP 10.1.204.41:39674(archappl): User="control", V4.13, 164 Channels, Priority=0
> TCP 10.1.204.41:39677(archappl): User="control", V4.13, 164 Channels, Priority=0
> TCP 10.1.204.41:39679(archappl): User="control", V4.13, 136 Channels, Priority=0
> TCP 10.1.204.41:39681(archappl): User="control", V4.13, 198 Channels, Priority=0
> TCP 10.1.204.41:39684(archappl): User="control", V4.13, 180 Channels, Priority=0
> TCP 10.1.204.41:39688(archappl): User="control", V4.13, 108 Channels, Priority=0
> TCP 10.1.204.41:39694(archappl): User="control", V4.13, 164 Channels, Priority=0
> TCP 10.1.204.41:39696(archappl): User="control", V4.13, 170 Channels, Priority=0
> 
> I can also reproduce this situation on my laptop with only three channels, when AA just started, 1 archived channel corresponded to 1 channel casr() displayed, but after 30 minutes, it became 1 archived channel corresponded to 8 channels casr() displayed.
> 
> epics> dbl
> aiExample
> calcExample
> calcExample1
> epics> 
> epics>
> epics> casr
> Channel Access Server V4.13
> Connected circuits:
> TCP 127.0.0.1:33826(debian-8): User="wanglin", V4.13, 1 Channels, Priority=0
> TCP 127.0.0.1:33827(debian-8): User="wanglin", V4.13, 1 Channels, Priority=0
> TCP 127.0.0.1:33828(debian-8): User="wanglin", V4.13, 1 Channels, Priority=0
> epics> 
> epics>
> epics> casr
> Channel Access Server V4.13
> Connected circuits:
> TCP 127.0.0.1:33826(debian-8): User="wanglin", V4.13, 8 Channels, Priority=0
> TCP 127.0.0.1:33827(debian-8): User="wanglin", V4.13, 8 Channels, Priority=0
> TCP 127.0.0.1:33828(debian-8): User="wanglin", V4.13, 8 Channels, Priority=0
> epics> 
> 
> 
> Any suggestion or hint is appreciated.
> 
> 
> Thanks,
> Lin
> 


Replies:
Re: Re: Archiver Appliance established multiple CA connections for one channel Wang, Lin
References:
Archiver Appliance established multiple CA connections for one channel Wang, Lin

Navigate by Date:
Prev: Re: 3.16.1: asynSetTraceMask and asynSetTraceIOMask Michael Davidsaver
Next: Re: Re: Archiver Appliance established multiple CA connections for one channel Wang, Lin
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
Navigate by Thread:
Prev: Archiver Appliance established multiple CA connections for one channel Wang, Lin
Next: Re: Re: Archiver Appliance established multiple CA connections for one channel Wang, Lin
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
ANJ, 13 Apr 2017 Valid HTML 4.01! · Home · News · About · Base · Modules · Extensions · Distributions · Download ·
· EPICS V4 · IRMIS · Talk · Bugs · Documents · Links · Licensing ·