Experimental Physics and
Industrial Control System

Hi Zhefu,

please set EPICS_CA_MAX_ARRAY_BYTES in your environment variables to your desired array size. Same discussion was here : https://epics.anl.gov/tech-talk/2010/msg00636.php

Hi all,

My problem is how to increase the number of elements of an array in waveform record of CA Lab. Below is the waveform record in demo.db, the default number of elements of an array are 2000. 

 

record(waveform, "caLab:test")

{

    field(DESC, "Double waveform record")

    field(PREC,0)

    field(NELM, 2000) 

    field(FTVL, "DOUBLE")

    #field(EGU, "mm")

    field (PINI, "YES")

}

I increased the value in the field NELM from 2000 to 30000 ( field(NELM, 30000) ), an error occured in the terminal:

    caLab:test *** CA error The requested data transfer is greater than available memory or EPICS_CA_MAX_ARRAY_BYTES

Therefore I try to change the default settings in demoIOC.cmd as follows and then restart the demoIOC: 

@echo off

#############################################################

set EPICS_CA_MAX_ARRAY_BYTES=1638400000  # I added the line here.

#############################################################

echo start demo IOC now

echo Type 'dbl' to get a list of all available records.

echo Type 'exit' to terminate this session.

echo ---

..\lib\softIoc.exe -D ..\lib\softIoc.dbd -d db\demo.db

:end

However, it doesn't work. No matter what value I set, the same error still exist in the terminal.

Any help will be appreciated and thanks in advance.

Zhefu