Re: callbackRequestDelayed question

[Michael Davidsaver via Core-talk <core-talk at aps.anl.gov>]

On 11/12/25 5:36 PM, Michael Davidsaver wrote:

  It thus appears to me that if the requested delay is less than epicsThreadSleepQuantum() then callbackRequestDelayed returns immediately.  Is that true?

The epicsTimer code is a little hard to follow, but I think yes.  More precisely, the timer is queued with a delay of 0, so it expires as soon as the worker thread wakes up.

Right, I was not remembering, or reading far enough down.  I did this test in a related context.  By scanning through ODLY of a calcout record, which also uses callbackRequestDelayed() .

... the effective count/scan rate is always high, and "saturates" somewhere between 150 and 200Hz.

Which is to say, when the delay goes below quantum/2 .

https://github.com/epics-base/epics-base/issues/106#issuecomment-1260232765