CA search back-off algorithm

Created by: willrogers

When JCA can't find a PV, it broadcasts again at increasing intervals, so that it doesn't create a lot of traffic with unanswered requests. It does this up to a maximum interval of 30 seconds, and this is not configurable (ChannelSearchManager.java).

private static final int MAX_SEND_INTERVAL_MS_DEFAULT = 30000;

The CA client in EPICS base does the same, but it backs off as far as 5 minutes by default, and this is configurable using the environment variable EPICS_CA_MAX_SEARCH_PERIOD - this is in udpiiu.cpp.

Do you know why the default is different? It appears to be the cause of increased network traffic between the Channel Archiver and the Archiver Appliance.