performance - What's the impact of insufficient space for shared memory file in Java HotSpot? -

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i have run lot of experiments (months of cpu time) have following warning in log:

java hotspot(tm) 64-bit server vm warning: insufficient space shared memory file

the experiments terminated without error, wonder may , may not evaluate them. so:

what's impact of insufficient space shared memory file in java hotspot?

details:

all have found shared memory file http://openjdk.java.net/groups/hotspot/docs/serviceability.html. this, seem lack of shared memory file has little effect on experiments :) not use profiler or evaluating experiments, log file have created successfully.

i measure how function foo() called. can lack of shared memory file change functional behaviour of program, should not evaluate experiments?

furthermore, measure runtime , memory requirements. did jvm's performance change, should not evaluate experiments?

finally, have experiments run distributed version of algorithm. jvm's performance change strongly, parallel functional behaviour changes if shared memory file missing not of parallel instances?

this warning means jvm unable use memory-mapped file hsperfdata hotspot performance counters. in case jvm falls standard (non-shared) memory performance counters if -xx:+perfdisablesharedmem specified.

this prevent jvm being automatically discovered utilities jps, jconsole or visualvm. jstat won't work. application not affected otherwise. runtime performance not changed.


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