Buffer Manager Information
This panel provides information about the performance of the Db2 buffer manager and the activity in each of the buffer pools.
This information helps you analyze buffer pool utilization.
________________ ZBMGR VTM O2 V550.#P SN12 11/05/13 14:05:45 2
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>
> *-BUFFER POOL B-GROUP BUFFER POOL
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> BUFFER MANAGER INFORMATION
BMGR
+ Current Number Open Datasets = 197
+ High Water Mark Open Datasets = 197
+ Maximum Number Open Datasets Allowed = 10000
+ Open Dataset Count In Active Pools = 250
+
+ *
+ Pool VP Pages Pages Getp Read Prefetch Write
+ ID Size Alloc In Use Rate I/O Rate Req Rate I/O Rate
+ ------ ------ ------ ------ -------- -------- -------- --------
+ BP0 5000 5000 29 138.00 7.00 .00 .00
+ BP1 2000 2000 0 .00 .00 .00 .00
+ BP2 2000 2000 1 6.00 1.00 .00 1.00
+ BP3 2000 2000 0 .00 .00 .00 .00
+ BP4 2000 2000 0 .00 .00 .00 .00
+ BP7 1000 1000 3 .00 .00 .00 .00
+ BP32K 250 250 2 .00 .00 .00 .00
+ BP8K0 10000 10000 2 10.00 .00 .00 .00
+ BP16K0 500 500 0 .00 .00 .00 .00
===============================================================================Highlighting
OMEGAMON®
for Db2 PE highlights some fields
in this panel to draw your attention to their current status.
| Field | Exception | Reason |
|---|---|---|
| Pages In Use | BMTH | The percentage of pages in use has reached the predetermined threshold. |
Navigation
For additional information about
- a buffer pool, move the cursor to the buffer pool line and press F11 (Zoom). For more information, see the description of panel Buffer Pool Detail.
- other topics, use the PF keys.
Fields
- Current® Number Open Datasets
- The number of data sets that are currently open in Db2.
- High Water Mark Open Datasets
- The largest number of data sets that were open simultaneously in Db2 since Db2 started.
- Maximum Number Open Datasets Allowed
- Determines how much initial memory to allocate for the data sets at startup time (defined by DSNZPARM DSMAX). The maximum number of data sets that can be open at one time is determined by TIOT SIZE, which is specified in SYS1.PARMLIB(ALLOCxx).
- Open Dataset Count in Active Pools
- The total number of opens issued for the buffer pools that are currently active. This value represents the number of times the data sets have been opened (and reopened) since Db2 started. (Buffer pools not currently in use might have issued opens that are not reflected in this count.)
- Pool ID
- The ID of the buffer pool.
- VP Size
- The number of buffers allocated for an active virtual buffer pool.
- Pages Alloc
- The number of pages currently allocated to the buffer pool. If a buffer pool is in use, Pages Alloc will be between the minimum and maximum values. Otherwise, it will be zero.
- Pages In Use
- The number of 4K, 8K, 16K, or 32K pages that are currently in use by the buffer pool.
- Getp Rate
- The number of Getpage requests per second made by the buffer pool.
- Read I/O Rate
- The total number of Read I/Os per second made by the buffer pool.
- Prefetch Req Rate
- The number of Sequential Prefetch and List Prefetch requests per second made by the buffer pool.
- Write I/O Rate
- The number of Write I/Os per second.