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I currently see in PROD the following:

5429.779: [Full GC [PSYoungGen: 13809K->0K(505216K)] [PSOldGen: 253802K->245481K(319488K)] 267612K->245481K(824704K) [PSPermGen: 70059K->70059K(118784K)], 0.5869143 secs] [Times: user=0.59 sys=0.00, real=0.59 secs]

I understand that A->B(C) means: A, before gc, B after gc, C heap without tenured and perm

What I don't understand is piece (outside all []s) which is 267612K->245481K(824704K). What does it refer to?

CAMOBAP
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2 Answers2

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It's the total of the generations, meaning the combined Heap Usage and total Heap Size in real memory (shown in braces).

In the given example, [PSYoungGen: 13809K->0K(505216K)] [PSOldGen: 253802K->245481K(319488K)] 267612K->245481K(824704K):

13809K + 253802K = 267612K

0K + 245481K = 245481K

505216K + 319488K = 824704K
Peter Lawrey
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May I advice you to use tools instead of manually reading logs.

Try HPJmeter tool

I find this tool best. Rest there are so many tools. Refer: Know of any Java garbage collection log analysis tools?

Generally as per my experience, its always better to use tools like above which simply imports GC log file & gives detailed graphs for different generations. If you go for manual reading, then your time will be more invested in reading than performance analysis.

Community
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Ravi K
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