[GEODE-10087] Enhance Off-heap memory fragmentation visibility

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.15.0
• Component/s: offheap, statistics
• Labels: pull-request-available
• Assignee: Alberto Gomez
• Reporter: Alberto Gomez
• Created: 28/Feb/22 15:17
• Updated: 22/Jun/22 20:46
• Resolved: 14/Apr/22 04:33

Description

As pointed out in https://cwiki.apache.org/confluence/display/GEODE/Enhance+Off-heap+memory+fragmentation+visibility:

"Even though Geode offers several stats related to the status of the off-heap memory area (usedMemory, freeMemory, fragmentation, largestFragment and fragments), the ones that provide information about the level of the fragmentation of the off-heap memory (fragmentation, largestFragment and fragments) are only updated when defragmentation is executed."

The visibility of the off-heap memory fragmentation status must be made more visible as proposed in the above RFC by means of:

• Updating the largestFragment stat periodically.
• Adding a new off-heap stat called "freedChunks" that will provide the number of elements in the tiny and huge lists. This stat will be periodically updated.

Issue Links

• links to: GitHub Pull Request #7407