Callback queue overflow

[Eric Norum <wenorum@lbl.gov>]

I have an EPICS R3.14.12 Linux IOC with about 24000 records, many of which are SCAN=“I/O Intr”.   I see occasional messages indicating callback request queue overflow:

-- 0:st.screen -- time-stamp -- May/16/17  1:29:02 --

callbackRequest: cbLow ring buffer full

-- 0:st.screen -- time-stamp -- May/16/17  1:29:59 --

-- 0:st.screen -- time-stamp -- May/16/17  2:59:02 --

callbackRequest: cbLow ring buffer full

-- 0:st.screen -- time-stamp -- May/16/17  2:59:54 --

-- 0:st.screen -- time-stamp -- May/16/17  7:59:02 --

callbackRequest: cbLow ring buffer full

callbackRequest: cbLow ring buffer full

-- 0:st.screen -- time-stamp -- May/16/17  8:00:02 --

I’ve attempted to increase the queue size, but maybe not enough:

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

# Override some sizes -- this IOC has *lots* of records

callbackSetQueueSize(10000)

dbPvdTableSize(8192)

Is there any downside to setting the callback queue size to something really large, says 50000 or more?  Is there something else I should try?

Thanks

-- 
Eric Norum
wenorum@lbl.gov