Glitch in JRCMD HEAP_DIAGNOSTICS Output When Memory Usage Increase > 2^31 Bytes (Doc ID 2125746.1)

Last updated on MARCH 08, 2017

Applies to:

Oracle JRockit - Version R28 to R28.2.0 [Release JRockit]
Information in this document applies to any platform.

Symptoms

On : R28.2.0 version, JVM and JDK

ACTUAL BEHAVIOR
---------------
Glitch in JRCMD HEAP_DIAGNOSTICS output when memory usage Increase > 2^31 bytes

when using "jrcmd <pid> heap_diagnostics", you might get between 2 data a memory usage increase > 2Gb.
In that case, some overflow seems to happen, as it results in very strange output, e.g.

39.9% 1462376k 12290755 +1462376k [C
62.0% 6028271k 18704693 +371591k [C
63.2% 6088333k 18269571 +60062k [C          (appears as first line of Detailed Heap)
68.1% 8261694k 18757064 -2020942k [C       (appears as last line of Detailed Heap and increase of 2,2Gb is displayed as negative: -2020942k)
68.4% 8164476k 18571186 -97218k [C
68.4% 8156222k 18575653 -8253k [C
68.3% 8134105k 18572070 -22117k [C
68.4% 8159198k 18587000 +25093k [C
30.4% 1394873k 18174567 +1624283k [C       (the increase is more than the total memory usage !)

EXPECTED BEHAVIOR
-----------------------
The increase should be positive even if greater than 2Gb

STEPS
-----------------------
The issue can be reproduced at will with the following steps:
1. monitor using heap_diagnostics
2. increase memory usage by a class for more than 2Gb
3. monitor using heap_diagnostics

BUSINESS IMPACT
-----------------------
The issue has the following business impact:
Due to this issue, users cannot monitor faithfully their heap

Cause

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