Experimental Physics and
Industrial Control System

Robert Soliday <[email protected]> · Mon, 01 Jul 2013 10:53:15 -0500

On 06/28/13 12:25, [email protected] wrote:

Hi Emmanuel,

Thank you for your reply. I think there may be a difference though. I
believe that the SCR applications use snapshots taken at periodic
intervals in time? What I had in mind was something that places monitors
on the process variables and archives the values only when they change.
The queries I described would then be done on that recorded data.

MASAR does look like a nice program though.

Thank you,
Patrick

store and query data as I have described, but I am wondering if I am
reinventing the wheel. Does a tool such as this already exist?

Yes.
You are describing a feature of Save/Compare/Restore applications.
SCR are also know as epics-backup application (i.e take a snapshot of a
running machine, compare 2 snapshots, compare a snapshot with the running
machine)

You next question is where to get such a piece of software. Well...
I am using SDDS save/compare/restore (very old)
SCORE may have the described feature as well (used at SNS and SLAC)

<Shameless plug for MASAR>
I am currently looking at MASAR part of epics-4, which is straight forward
to install, but still in development.
For example, comparisons of 2 snapshots using the pyQt GUI is missing.
A CSS GUI is also a work-in-progress.
At this time, most of the development is at the GUI level
So if you don't mind a text output (i.e. in a terminal), you can use MASAR
with its python API and have something working by tonight.
</Shameless plug for MASAR>

That sounds a lot like our sddslogonchange logger paired with our PV

History Tool GUI. We have the logger running all the time and recording

any changes to individual PVs with an optional tolerance level. We can

then use our PV History Tool to plot the changes and to restore the PVs

to any given time.

--Bob Soliday

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System