Experimental Physics and
Industrial Control System

Emmanuel Mayssat <[email protected]> · Wed, 27 Jul 2005 19:45:01 -0700

Hello again,

On one of my ioc, I noticed that the processing of soft PVs was slow.
Sequencer records would not process according to their delay
configuration.

I immediately thought that the computer was overloaded.
But the 1-min cpu load was less than 1% !!!!

I tried to renice (man renice on linux for more info) the priority of my
ioc process down, but always slow. Memory was ok, disks were ok, cpu
load seemed ok. What could be wrong?

Then I though that a bug in my drivers could be the source, but the soft
records/sequencer are actually native to epics. ( so no custom
rsets/dsets)

Now I tried to split the single ioc process into several processes. And
then .. despite the warning messages(the processes were running on the
same port), surprise everything runs faster.
What is different?

What is different is that now I have several scheduling queues instead
of one ( 1 queue per process I believe). Is there a limitation on the
scheduling queues? Maybe an epics bug?

-- 
Emmanuel Mayssat <[email protected]>

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System