EPICS Controls 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  <20102011  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  <20102011  2012  2013  2014  2015  2016  2017  2018  2019  2020  2021  2022  2023  2024 
<== Date ==> <== Thread ==>

Subject: Re: cac_select_io Segmentation fault
From: Ralph Lange <[email protected]>
To: Al Honey <[email protected]>
Cc: EPICS Tech Talk <[email protected]>
Date: Wed, 07 Apr 2010 15:15:01 -0400
Hello Al,

sorry if I sounded rough - no intention!

I've been working for many years with accelerators, which might not have the extreme deployment restrictions that a telescope has, but also with accelerators some things come with a once-in-a-year window.

But:
If you are developing (or moving) a multi-threaded client application on Solaris 10, and found out that 3.13 is not thread safe, I would think it is safe to say that this application was never running successfully in that configuration before.
Which means, that you have to do the application and regression testing for this app, anyway.
So: Why don't you build your application against 3.14? You don't need to switch your whole installation over to a new base release. Just build your app using 3.14, so that it works. If you want to make sure nothing unexpected happens, build it statically, so that it doesn't load any EPICS libraries dynamically, and you don't have to have 3.14 libraries on your production system.


As others said - it it perfectly legal to mix and match EPICS base versions, and BESSY is running an accelerator using a wild mixture of roughly half a dozen EPICS releases between 3.13.0.beta4 and 3.14.10.
We have been using statically built clients for a long time. Put the binary on the system - run it. No other libraries dynamically linked except for libc and the other system libraries. (We found these need to be shared libs - and EPICS base does the build that way - else you may run into trouble with different hardware series that only claimed to be binary compatible.)


Nice side effect: Running your application 3.14 based could be seen as a low-impact regression test for 3.14, so it might make swapping more to 3.14 an easier step.

Good luck!
Ralph


On Wed 07 Apr 2010 14:51:04 Al Honey wrote:
Hi Ralph
Thanks for your input. I can use that with management.

The issue is Time and manpower :)
With an observatory, which has: 2 telescopes; 12 instruments; and
multiple adaptive optic and interferometric modes, regression testing
can take any where up to a year, as one must wait for each telescope
configuration to occur. We typically only do upgrades on engineering
nights (there are very few in any given year) and some configurations
never occur on engineering nights. Those configurations would have to be
specifically requested (with an all night plan in place). That makes it
hard to deploy anything that affects all systems, as would be the case
with an EPICS version upgrade. We can do some partitioning of releases
(e.g. deploy for the telescope drive systems independently on each
telescope, then the AO systems,...) = but it is still a tough nut.


Thanks,
Al


Replies:
RE: cac_select_io Segmentation fault Al Honey
References:
cac_select_io Segmentation fault Al Honey
Re: cac_select_io Segmentation fault Ralph Lange

Navigate by Date:
Prev: Re: EDM text entry: segmentation fault Dmitry Teytelman
Next: RE: cac_select_io Segmentation fault Al Honey
Index: 1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  <20102011  2012  2013  2014  2015  2016  2017  2018  2019  2020  2021  2022  2023  2024 
Navigate by Thread:
Prev: Re: cac_select_io Segmentation fault Ralph Lange
Next: RE: cac_select_io Segmentation fault Al Honey
Index: 1994  1995  1996  1997  1998  1999  2000  2001  2002  2003  2004  2005  2006  2007  2008  2009  <20102011  2012  2013  2014  2015  2016  2017  2018  2019  2020  2021  2022  2023  2024 
ANJ, 02 Sep 2010 Valid HTML 4.01! · Home · News · About · Base · Modules · Extensions · Distributions · Download ·
· Search · EPICS V4 · IRMIS · Talk · Bugs · Documents · Links · Licensing ·