Experimental Physics and
Industrial Control System

Kevin Meyer <[email protected]> · Tue, 29 Nov 2016 10:31:09 +0100 (CET)

Responses inline, below, but basically: the SNL thread is still running:

----- On 28 Nov, 2016, at 17:31, Kasemir, Kay [email protected] wrote:

>>In one of the sequencers, I have a call out to to a Python script that calls a
>>web service (to Olog, to create an electronic lab-book entry).
> 
> Is that the one that's occasionally hanging up?
> 
> Are you calling out to python from somewhere within the SNL code, like
> 
> when (..)
> {
>    .. call out to python
> }
> 
> ?
> 
> I assume that all the SNL code is executed within some 'main' thread of the
> sequencer.
> Maybe the call out to python hangs, so the core SNL thread is stuck and no
> longer updating anything.
> 
> 
> --> Put some printouts in there to assert that you're not stuck:
> 
> 
> when (..)
> {
>   puts(">>> Calling python");
>    .. call out to python
>   puts("<<< Done");
> }
> 
> -Kay

I attach my edited log messages. I've removed spurious details from other state machines...
sup-sm-pos is the sequencer of interest.

[time29.9][host][sup-sm-pos:pid1][info] Transition from Ready to Start
[time29.9][host][sup-sm-pos:pid1][info] Entering state Start 
[time29.9][host][sup-sm-pos:pid1][info] Call to elogbook_log_pos_status with handle 0

...this shows that the call to Python has returned.

[time30.0][host]...
[time30.0][host]...
[time30.0][host]...
[time30.0][host]...
[time30.0][host]...
[time30.0][host]...
[time30.1][host]...
[time30.1][host]...
[time30.2][host]...
[time30.4][host]...
[time30.4][host]...
[time30.4][host]...
[time30.4][host]...
[time30.7][host][sup-sm-pos:pid1][info] Call to elogbook_log_pos_status returned 0

...this shows that the call to Python has returned.

[time30.9][host]...
[time30.9][host]...
[time31.4][host][sup-sm-pos:pid1][info] Transition from Start to Wait <-- "entry" block
[time30.7][host][sup-sm-pos:pid1][info] Call to elogbook_log_pos_status returned 0
[time31.4][host][sup-sm-pos:pid1][info] Transition from Start to Wait <-- simulated "body" block
[time31.4][host][sup-sm-pos:pid1][info] Entering state Wait 
[time32.4][host]...
[time32.4][host]...
[time33.4][host][sup-sm-pos:pid1][info] Transition from Wait to PreChecks
[time33.4][host][sup-sm-pos:pid1][info] Entering state PreChecks 
[time34.7][host][sup-sm-pos:pid1][info] Transition from PreChecks to FinalPrep
[time34.7][host][sup-sm-pos:pid1][info] Entering state FinalPrep 

... Here, the sup-sm-pos has a "guard" waiting for COS to change to "Executing"

[time34.7][host]...
[time35.4][host][CommonOperationalStates:pid2][info] Goto  COSExecuting
[time35.4][host][CommonOperationalStates:pid2][info] State COSExecuting: Do (once)

Here, COS goes to Executing, as can be confirmed with a "caget" from the terminal.
But the sup-sm-pos process never gets out of FinalPrep...

--
Kevin Meyer
Cosylab, Ljubljana, Slovenia
Telephone: +386-(0)1-320-47-82   Mobile: +386-(0)70-260-321

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System