Experimental Physics and
Industrial Control System

Hi Adam,

 

Since you are using Debian flavors, you may take a look at the Debian package “sysv-rc-softioc” which wraps procServ to manage multiple IOCs on a host. I usually run tens of IOCs (or about 100 IOCs) on a ~$4K Linux server.

https://epicsdeb.bnl.gov/debian/

 

If you have difficulty installing the Debian package “sysv-rc-softioc” above, you may try the tool I recently developed below which is generic for all systemd-based Linux (Debian, RedHat, …).

(systemd-style scripts for procServ with the intent of running an EPICS IOC):

https://github.com/NSLS-II/systemd-softioc

 

Q:“What is the difference between spawning multiple IOCs through running your st.cmd for each and instead spawning them using procServ?”

A: Yes, you can simply type “./st.cmd &” in a terminal to start an IOC (or use tools such as screen, tmux, nohup to start an IOC). I tried all of these methods when I was a graduate student decades ago. But I like “procServ” the most (especially the Debian package “sysv-rc-softioc” which was originally developed by Michael Davidsaver) after I started my first job at NSLS-2. Since “sysv-rc-softioc” or “systemd-softioc” is a piece of software and it has some strict directory structure requirements, you need to learn how to use it properly. Once you know how to use all kinds of tools, you will know the difference and you will pick up the tool which is most comfortable for yourself.

 

Take your time to try sysv-rc-softioc (or systemd-softioc) and you will not regret spending your time on it.

 

Good luck!

Yong

 

Hey Dave,

 

Thanks for the information, for platform we will be using Debian flavors of linux as the host for the IOCs and so far have not encountered running multiple IOCs of the epics 3/7.  I was concerned with spawning out so many IOC instances if I did go with the design of one ioc one device (looking at say 30+ IOCs on one host vs combining down to ~5).  I can see the benefit of efficiency when records need to communicate between each other but in this case the digitizers/dmms do not have any dependencies on each other. 

 

Couple other thoughts

 

I was looking at starting to use procServ but was a little confused from reading about the documentation on its use.  What is the difference between spawning multiple IOCs through running your st.cmd for each and instead spawning them using procServ?  Is the IOC treated differently in linux when using procServ to start them?

 

Will I run into resource issues (on a highend desktop) spawning so many IOCs (~30) on one host (I did implement Ralphs script already to solve the multiple ioc ca issue)?

 

Are there concerns when running say 8 devices using streamdevice in a single IOC, I would assume there might be some delay when streamdevice has to make multiple calls in the same IOC?