Corrupted data in PROMON "Status: Buffer Cache" causes performance degradation

Performance degradation due to corrupted data in "Promon:Status: Buffer Cache”.
“Used buffers” are larger than “Total buffers” in the "PROMON > R&D > Status Displays > Buffer Cache"
 

The issue with the alternative buffer pool having more entries than assigned space is that, when an entry on LRU2 is dequeued from LRU2 and moved to APW quene for page writer to flush, during that time, another buffers can be added to LRU2. Later when the page writer flush the buffer and put it back on LRU2, the LRU chain might be already full.

This causes LRU2 entries exceeded the allocated numbers. Performance degrades when too many buffers on LRU are moved to LRU2 chain and causes a low buffer hit ratio on the general buffer pool low. The issue found only with object-level B2. 

Fixed version(s): 11.7.6.0, OpenEdge 12.2

Restart the database and resize the Alternate Buffer Pool to include 1 cluster of blocks for each object assigned to it in addition to the considered size of the objects blocks.