Hierarchy
SAP_BASIS (Software Component) SAP Basis Component⤷
BC-DB-DB2 (Application Component) DB2 for z/OS⤷
STU3 (Package) Development Class for Database Monitor
Basic Data
| Data Element | DB2CHPEFF |
| Short Description | Hiperpool efficiency |
Data Type
| Category of Dictionary Type | D | Domain |
| Type of Object Referenced | No Information | |
| Domain / Name of Reference Type | DB2CHAR06 | |
| Data Type | CHAR | Character String |
| Length | 6 | |
| Decimal Places | 0 | |
| Output Length | 6 | |
| Value Table |
Further Characteristics
| Search Help: Name | ||
| Search Help: Parameters | ||
| Parameter ID | ||
| Default Component name | ||
| Change document | ||
| No Input History | ||
| Basic direction is set to LTR | ||
| No BIDI Filtering |
Field Label
| Length | Field Label | |
| Short | 0 | |
| Medium | 15 | HP efficiency |
| Long | 20 | Hiperpool efficiency |
| Heading | 0 |
Documentation
Definition
The hiperpool efficiency is defined as
100 * (QBSTHRE + QBSTHRA + QBSTARA) / (QBSTHWR + QBSTHWA + QBSTAWA)
where
QBSTHRE:
Number of successful synchronous requests to move a page from a hiperpool to a virtual buffer pool.
On behalf of a page access request, DB2 moves a page from a hiperpool to a virtual buffer pool (if the page is found in the hiperpool).
QBSTHRA:
Number of pages moved successfully from the hiperpool to the virtual buffer pool asynchronously.
Asynchronous movement occurs under the control of an asynchronous DB2 system task such as sequential prefetch. This count does not include pages moved by the asynchronous data mover facility.
QBSTARA:
Number of pages moved successfully from the hiperpool to the virtual buffer pool by the asynchronous data mover facility.
Only asynchronous DB2 system tasks, such as sequential prefetch, perform this type of page movement.
QBSTHWR:
Number of successful requests issued by DB2 to synchronously move a page from the virtual buffer pool to the hiperpool. In other words, this is the number of times that pages are cached in the hiperpool.
Before reusing a buffer in a virtual pool for a page request, its old content must be saved in a hiperpool if it is a candidate for hiperpool caching. (Data accessed by queries processed in parallel is not cached in a hiperpool.)
QBSTHWA:
Number of pages successfully moved asynchronously from the virtual buffer pool to the hiperpool.
Asynchronous movement occurs under the control of an asynchronous DB2 system task such as sequential prefetch. This count does not include pages moved by the asynchronous data mover facility.
QBSTAWA
Number of pages moved successfully from the virtual buffer pool to the hiperpool by the asynchronous data mover facility.
Only asynchronous DB2 system tasks, such as sequential prefetch, perform this type of page movement
History
| Last changed by/on | SAP | 20070813 |
| SAP Release Created in | 710 |
