jmap appears slower under Java 7, slows down JVM -


we've been using jmap ~2 years measure heap size on large, multi-server app, running under java 6. take measurement every minute. each measurement took (elapsed time) less 1 second.

we're testing same app under java 7. , jmap takes 10 seconds, 20 seconds, longer, , seems slow down (or perhaps stop!) jvm during time.

the difference see in jmap output (between java 6 , java 7) additional information how many strings interned. (and seems that's part slower.)

does know going on, or changed in jmap or java 7 might cause this?

we're testing using "jstat -gc" same information, , far seems faster, , not appear cause app slowdowns saw jmap. there other suggestions how measure heap size, quickly?

any thoughts welcome, in advance.

i quite oracle mission control monitoring heap size. has many more options, works charm monitor heap size.


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