Experimental Physics and
Industrial Control System

[email protected] (Jeff Hill) · Thu, 24 Sep 1998 12:44:06 -0600

All

We have recently discovered a bug where the 3.12 CA clients do not disconnect
from an IOC when the client's last channel on this IOC is deleted. If the client creates a
new channel on this IOC it will continue to reuse the connection that was not closed,
but if the client continues to run with no channel on this IOC then the connection
will remain open. When the client quits then all connections to IOCs are
closed. So this problem is mostly benign, but it could cause IOC resource consumption 
that is higher than in past releases.

Symptoms:
In the IOC "casr" reports "Channel Count=0" for one or more clients.

Versions:
EPICS R3.12 beta9 - R3.12 beta12

Associated clients (all of the following must be true):
o clients that run continuouly for extended periods without exiting
o clients that delete channels routinely during operation (prior to exiting)
	- dm and medm are likely candidates
o clients that connect to multiple (probably many) IOCs

Impact:
o memory and file descriptor consumption load on IOCs could be higher 
than in past releases
o note however that EPICS 3.12 in general uses less IOC memory for clients than 
in the past

Jeff
______________________________________________________
Jeffrey O. Hill                      Internet     [email protected]
LANL MS H820                    Voice         505 665 1831
Los Alamos NM 87545 USA   FAX          505 665 5107

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System