Gotcha: Save on objects and get more Full GCs.


We have system which is latency sensive and object light. However as we tuned the system to run less minor collections we saw the number of Full GCs increase.


Some investigation found that there is a timer for RMI which checks if a GC has occurred in the last hour and if it hasn't performs a Full GC. :P If you are not really using RMI, this is undesireable.


There are two command line options which can be increased to reduce the number of these only-for-RMI Full GCs. Increasing just one has no effect. The defaults are:


-Dsun.rmi.dgc.server.gcInterval=3600000
-Dsun.rmi.dgc.client.gcInterval=3600000


For more details bug id 6200091
See line 109 of The sun.misc.GC.Daemon class

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