Try OpenEdge Now
skip to main content
Database Administration
Reference : PROMON Utility : R&D Other Displays : Checkpoints
 
Checkpoints
Displays information about checkpoints.

PROMON Checkpoints display

The following shows a sample Checkpoints display.
03/24/15 Checkpoints
17:50:12

Ckpt --------- Database Writes ---------- ------ Performance Timings ---------
No. Time Len Freq Dirty CPT Q Scan APW Q DB Writes Bi Writes Duration Sync Time DB Write Bi Write NumChkpt
56 17:50:07 49 0 24 0 0 0 0 19 0.02 0.00 0.00 0.01 13

55 17:50:07 0 0 27 0 0 0 13 19 0.02 0.00 0.00 0.01 14
54 17:50:03 4 4 21 0 0 0 14 19 0.02 0.00 0.00 0.02 7
53 17:50:03 0 0 22 0 0 0 7 19 0.02 0.01 0.00 0.02 15
52 17:50:02 1 1 32 0 0 0 15 19 0.03 0.00 0.00 0.02 17
51 17:49:14 48 48 30 0 0 0 17 9 0.01 0.00 0.00 0.01 13
50 17:49:07 7 7 17 0 0 0 13 19 0.02 0.00 0.00 0.01 4
49 17:49:06 1 1 24 0 0 0 4 19 0.02 0.00 0.00 0.01 20

Enter <return>, R, U, P, T, or X (? for help):
This display shows the following information:
*Ckpt. No. — The sequential number assigned to the checkpoint
*Time — The time the checkpoint began
*Len — The length of time required to complete the checkpoint. The checkpoint is not considered completed until all dirty buffers on the checkpoint queue have been written out. This is either done over time by the APWs between checkpoints or is forced at the next checkpoint (DB Writes).
*Freq — The length of time between checkpoint starts
*Dirty — The number of modified buffers scheduled to be written
*Database Writes
*CPT Q — The number of buffers written from the checkpoint queue by the APWs
*Scan — The number of buffers written by the APWs during the scan cycle
*APW Q — The number of buffers written by the APW queue and replaced on the least recently used (LRU) chain by APWs
*DB Writes — The total number of database buffers written all at once at the end of the checkpoint
*Bi Writes — The total number of BI buffers written from the BI buffer pool all at once at the end of the checkpoint
*Performance Timings
*Duration — The time to do the housekeeping of the checkpoint. This includes the time to write the active recovery log buffers to disk, write any outstanding dirty buffers marked at the previous checkpoint, scan the database buffer pools for dirty buffers marking them as needing to be written to disk prior to the start of the next check point (putting them on the checkpoint queue) and to perform the file system synchronization (Sync Time).
*Sync Time — The time to perform the file system synchronization of the checkpoint (fdatasync() on UNIX, FlushFileBuffers() in Windows)
*DB Write — The time in seconds to scan and write the buffers from the database buffer pool
*Bi Write — The time in seconds to write the buffers from the -bibufs buffer pool
*NumChkpt — The number of buffers checkpointed (written from the database buffer pool)