Experimental Physics and
Industrial Control System

"Daykin, Evan via Tech-talk" <tech-talk at aps.anl.gov> · Thu, 5 Aug 2021 16:25:05 +0000

Yes, there are other support modules:
Calc, Tbuf (time buffer for pico8), PyDevSup, SScan, autosave, iocstats, and caputlog.

If I set the IOC back to 1 thread with all four cards, the shell is spammed with output:

DIAG_MTCA17:PICO8_CH0:MIN_ASUB: repeated sample (diff=0.000000) [1 times]
DIAG_MTCA17:PICO8_CH1:MIN_ASUB: repeated sample (diff=0.000000) [1 times]
DIAG_MTCA17:PICO8_CH2:MIN_ASUB: repeated sample (diff=0.000000) [1 times]
DIAG_MTCA17:PICO8_CH3:MIN_ASUB: repeated sample (diff=0.000000) [1 times]
DIAG_MTCA17:PICO8_CH4:MIN_ASUB: repeated sample (diff=0.000000) [1 times]
DIAG_MTCA17:PICO8_CH5:MIN_ASUB: repeated sample (diff=0.000000) [1 times]
DIAG_MTCA17:PICO8_CH6:MIN_ASUB: repeated sample (diff=0.000000) [1 times]
DIAG_MTCA17:PICO8_CH7:MIN_ASUB: repeated sample (diff=0.000000) [1 times]
DIAG_MTCA17:PICO8_CH0:MAX_ASUB: repeated sample (diff=0.000000) [1 times]
DIAG_MTCA17:PICO8_CH1:MAX_ASUB: repeated sample (diff=0.000000) [1 times]
DIAG_MTCA17:PICO8_CH2:MAX_ASUB: repeated sample (diff=0.000000) [1 times]
DIAG_MTCA17:PICO8_CH3:MAX_ASUB: repeated sample (diff=0.000000) [1 times]
DIAG_MTCA17:PICO8_CH4:MAX_ASUB: repeated sample (diff=0.000000) [1 times]
DIAG_MTCA17:PICO8_CH5:MAX_ASUB: repeated sample (diff=0.000000) [1 times]
DIAG_MTCA17:PICO8_CH6:MAX_ASUB: repeated sample (diff=0.000000) [1 times]
DIAG_MTCA17:PICO8_CH7:MAX_ASUB: repeated sample (diff=0.000000) [1 times]

I assume this is because there is some bottleneck. If I reduce to 1 thread and 1 hardware device, the output is gone. So, with the following in mind:

-1 thread is too slow for four devices
-multiple threads is untested

Is the best workaround to split these into multiple IOCs?  That way, I assume, there is parallel processing without untested resource contention.

-----Original Message-----
From: Michael Davidsaver <mdavidsaver at gmail.com> 
Sent: Thursday, August 5, 2021 11:41 AM
To: Johnson, Andrew N. <anj at anl.gov>; Daykin, Evan <daykin at frib.msu.edu>
Cc: EPICS tech-talk <tech-talk at aps.anl.gov>; Rivers, Mark L. <rivers at cars.uchicago.edu>
Subject: Re: cbLow consumption randomly stopping

[EXTERNAL] This email originated from outside of FRIB

On 8/5/21 8:30 AM, Johnson, Andrew N. wrote:
> Hi Evan,
> 
> Does this IOC load /any/ other EPICS drivers or device support at all (other than the standard ones that come with Base)?

> Your configuration with multiple callback threads is unusual, and a lot of device/driver support might not have been written or tested with the thought that there could more than one such callback in mind, so any such support code might be contributing to this issue.

I'll second this.  I never tested the pico8 driver (or any of my
drivers) with parallel callbacks enabled.

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System