Release 10.1A: OpenEdge Data Management:
Database Administration

Buffer Cache

Displays status information about buffers. Figure 19–22 shows a sample Buffer Cache Status display.

09/25/03              Status: Buffer Cache 16:21 Total buffers:                   170 Hash Table Size:                 43 Used Buffers:                    57 Empty Buffers:                   113 On lru Chain:                    168 On apw queue:                    0 On ckp queue:                    0 Modified buffers:                170 Marked for ckp:                  0 Last checkpoint number:          0

Figure 19–22: PROMON Buffer Cache Status display

The display contains the following fields:

Total buffers — The total number of buffers in the buffer cache.
Hash Table Size — The size of the buffer hash table.
Used Buffers — The number of buffers currently in use.
Empty Buffers — The number of empty buffers.
On lru Chain — The number of buffers on the least recently used (LRU) chain.
On apw queue — The number of buffers on the page writer queue.
On ckp queue — The number of buffers on the checkpoint queue.
Modified buffers — The number of dirty (modified) buffers.
Marked for ckp — The number of buffers currently marked for checkpoint.
Last checkpoint number — The most recent checkpoint number. As checkpoints begin, they are assigned a sequential number from the start of the session. The number is also the number of checkpoints that have occurred.