Eclipse MAT OQL: Gathering Basic Information from Heap Dump

All Environment Variables used by JVM process

SELECT map.key.toString() AS key, map.value.toString() AS value FROM OBJECTS ( SELECT OBJECTS o[0:-1] AS kv FROM OBJECTS ( SELECT OBJECTS c.theEnvironment FROM java.lang.Class c WHERE (c.@displayName.contains("class java.lang.ProcessEnvironment") and (c.theEnvironment != null)) ) o ) map

All System Properties used by JVM process

SELECT map.key.toString() AS key, map.value.toString() AS value FROM OBJECTS ( SELECT OBJECTS o[0:-1] AS kv FROM OBJECTS ( SELECT OBJECTS c.props FROM java.lang.Class c WHERE (c.@displayName.contains("class java.lang.System") and (c.props != null)) ) o ) map

Heap Dump Epoch time

SELECT c.CURRT AS HeapDumpEpochTime FROM java.lang.Class c WHERE c.@displayName.contains("class sun.util.calendar.ZoneInfoFile ")



Then copy the value displayed and use a site such as https://www.epochconverter.com/ to convert it to Human Readable time (when heap dump was collected)




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