Buffer pool monitors
Monitor | Title | View name | Description, Parameters, Warning |
|---|---|---|---|
BPUSE | Buffer Pool Percent in Use | DBPUSE | Reports the percentage of buffer pool pages that are specified as in use by a thread The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
BPUTL | Buffer Pool Percent Utilization | DBPUTL | Reports the percentage of buffer pool usage Unavailable buffer pool pages are assessed whether they are in use or being updated. The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
DESRD | Number of Pages for Which Destructive Read Requested | DDESRD | Reports the number of pages for which a destructive read was requested during the sampling period Parameters: [buffer pool id] |
DWTX | Vertical Deferred Write Threshold Reached | DDWTX | Reports the number of times that a buffer pool Vertical Deferred Write threshold was exceeded during the sampling period (QBSTDWV) When the number of updated pages for a given data set exceeds the Vertical Deferred Write threshold, deferred writes are initiated for that data set. The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
GCAST | GBP Castout Requests | DGCAST | Reports the number of times group buffer pool castout was initiated because the class castout threshold was detected or the group buffer pool castout threshold was detected during the sampling period (QBGLCT, QBGLGT) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
GCTPG | GBP Castout Pages | DGCTPG | Reports the number of pages cast out from the group buffer pool to DASD during the sampling period (QBGLRC) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
GETPG | GETPAGE Requests | DGETPG | Reports the number of GETPAGE requests during the sampling period The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
GETRI | GETPAGE (GET) Requests per Read I/O (RIO) | DGETRI | Reports the average number of GETPAGE requests per read I/O during the sampling period The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
GFAIL | GBP Failures | DGFAIL | Reports the number of GBP-write requests that could not be completed because of a lack of GBP storage resources (QBGLWF) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
GOTHR | GBP Other Requests | DGOTHR | Reports the number of other coupling facility requests that are not counted in any of the other QBGL fields during the sampling period (QBGLOS) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
GPGWR | GBP Pages Written | DGPGWR | Reports the number of changed or clean pages written to the group buffer pool during the sampling period (QBGLSW, QBGLWC, QBGLAW, QBGLAC) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
GRDIN | GBP Read Requests–Interest | DGRDIN | Reports the number of coupling facility read requests caused by the buffer being marked invalid or the requested page was not found in the buffer pool during the sampling period (QBGLXR, QBGLMR, QBGLAR) Data is not returned from the group buffer pool and a directory entry is created if it does not already exist. This situation means another Db2 in the group has R/W interest in the page set or partition. The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
GRDRQ | GBP Read Requests with Data | DGRDRQ | Reports the number of coupling facility read requests with data returned during the sampling period (QBGLXD, QBGLMD, QBGLAD) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
HPRDF | Read Pages Failures | DHPRDF | Reports the number of read page request failures because the backing expanded store was stolen (castout=yes) or some other error occurred during the sampling period (QBSTHRF + QBSTARF) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
HPVPA | Successful Asynchronous Reads for HP-to-VP | DHPVPA | Reports the number of successful asynchronous page moves from the hiperpool to the virtual buffer pool during the sampling interval (QBSTHRA + QBSTARA) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
HPVPS | Successful Synchronous Reads for HP-to-VP | DHPVPS | Reports the number of successful synchronous reads to move a page from a hiperpool to a virtual buffer pool during the sampling period (QBSTHRE) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
HPWRF | Write Page Failures | DHPWRF | Reports the number of write page request failures because the backing expanded store was stolen (castout=yes) or some other error occurred during the sampling period (QBSTHWF + QBSTAWF) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
LSTPF | Number of List Prefetch Requests | DLSTPF | Reports the number of buffer pool list prefetch requests during the sampling period (QBSTLPF) If the monitor is started without a buffer pool ID, the sum of prefetch requests for all active buffer pools are reported. Parameters: [buffer pool id] |
MAXPF | Maximum Concurrent Parallel I/O Prefetch Streams | DMAXPF | Reports the maximum number of concurrent prefetch I/O streams allocated for parallel processing queries during the sampling interval (QBSTXIS) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
MIAPF | Multi-Index Failures | DMIAPF | Reports the number of RID list processing failures that occurred during the sampling period List processing failures are attributed to SQL routines that Explain indicates will use multi-index access paths, but fail to do so at runtime because storage limits or RID thresholds are exceeded. Parameters: [STOR|#RIDS] |
MIGDS | Migrated Data Sets | DMIGDS | Reports the number of data sets that migrated from a buffer pool during the sampling period The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
PFDIO | Dynamic Prefetch Read I/O | DPFDIO | Reports the number of asynchronous read I/Os that were due to dynamic prefetch during the sampling period (QBSTDIO) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
PFDPG | Dynamic Prefetch Pages Read | DPFDPG | Reports the number of asynchronous page reads that were due to dynamic prefetch during the sampling period (QBSTDPP) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
PFDRQ | Dynamic Prefetch Requests | DPFDRQ | Reports the number of dynamic prefetch requests during the sampling interval (QBSTDPF) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
PFIOF | Prefetch I/O Failures | DPFIOF | Reports the number of prefetch I/O stream request failures that were due to buffer storage shortages during the sampling period (QBSTJIS) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
PFLIO | List Prefetch Read I/O | DPFLIO | Reports the number of asynchronous read I/Os caused by list prefetch to a buffer pool during the sampling period (QBSTLIO) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
PFLPG | List Prefetch Pages Read | DPFLPG | Reports the number of asynchronous page reads resulting from a list prefetch during the sampling period (QBSTLPP) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
PFLRQ | List Prefetch Requests | DPFLRQ | Reports the number of list prefetch requests during the sampling period (QBSTLPF) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
PFSIO | Sequential Prefetch Read I/O | DPFSIO | Reports the number of asynchronous read I/Os caused by sequential prefetch during the sampling period (QBSTPIO) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
PFSPG | Sequential Prefetch Pages Read | DPFSPG | Reports the number of asynchronous page reads caused by sequential prefetch during the sampling period (QBSTSPP) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
PFSRQ | Sequential Prefetch Requests | DPFSRQ | Reports the number of sequential prefetch requests for a buffer pool during the sampling period (QBSTSEQ) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
PFTIO | Total Prefetch Read I/O | DPFTIO | Reports the number of asynchronous read I/Os caused by prefetch during the sampling period The count is calculated as the sum (QBSTPIO + QBSTLIO + QBSTDIO). The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
PFTPG | Total Prefetch Pages Read | DPFTPG | Reports the number of total asynchronous page reads caused by prefetch during the sampling period The count is calculated as the sum (QBSTSPP + QBSTLPP + QBSTDPP). The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9|BP16K0–BP16K9| BP32K–BP32K9] |
PFTRQ | Total Prefetch Requests | DPFTRQ | Reports the number of total prefetch requests from an active buffer pool during the sampling period The count is calculated as the sum (QBSTSEQ + QBSLTLPF + QBSTDPF). The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
PIO | Prefetch Read I/O | DPIO | Reports the number of prefetch read I/Os that occurred during the sampling period The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
PRL12 | Prefetch Reduced to 1/2 | DPRL12 | Reports the number of times that a prefetch quantity is reduced from normal to one-half during the sampling period (QBSTPL1) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
PRL14 | Prefetch Reduced to 1/4 | DPRL14 | Reports the number of times that a prefetch quantity is reduced from one-half of normal to one-quarter during the sampling period (QBSTPL2) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
PRLGF | Conditional GETPAGE Failures | DPRLGF | Reports the number of times that a conditional GETPAGE request cannot be satisfied from a buffer pool during the sampling period (QBSTNGT) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
PRLQ | Parallel Query Requests | DPRLQ | Reports the number of parallel processing requests in the buffer pool during the sampling period (QBSTPQO) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
PRLQF | Parallel Query Request Failures | DPRLQF | Reports the number of times that Db2 cannot allocate the requested number of buffer pages to allow a parallel group to run to the planned degree during the sampling period (QBSTPQF) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
PWS | System Pages Written | DPWS | Reports the number of database system pages that were written during the sampling period The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
PWSWI | System Pages Written (PWS) per Write I/O (WIO) | DPWSWI | Reports the average number of system pages written per write I/O during the sampling period The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
RIDUT | RID Pool Percent Utilization | DRIDUT | Reports the percentage of RID control blocks in use during the sampling period The percentage is calculated as the number of used RID blocks divided by the total number of available RID blocks. Parameters: none |
RIO | Read I/O Activity | DRIO | Reports the number of media manager read I/O requests during the sampling period The counts are either a GETPAGE request or a multiple page request for a prefetch function. The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
RTO | Recall Time-Outs | DRTO | Shows the number of HSM recall timeouts that occurred during the sampling period The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
RWP | Reads with Paging | DRWP | Reports the number of reads with paging during the sampling period The reported value is the number of times a buffer did not have real-storage frame backing when being PAGEFIXed to perform a read I/O. The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
SEQIO | Sequential Read I/O Requests | DSEQIO | Reports the number of synchronous read I/Os issued by sequential access requesters in the sampling period (QBSTSIO) A synchronous read I/O occurs as a result of a disabled prefetch or when the requested pages are not consecutive. The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
SEQPG | Sequential GETPAGE Requests | DSEQPG | Reports the number of GETPAGE requests issued by sequential access requesters during the sampling period (QBSTSGT) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
SWS | System Page Updates | DSWS | Reports the number of system updates (SWS) during the sampling period The count changes by increments of one each time a row in a database system page is updated. The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
SWSPW | System Page Updates (SWS) per System Pages Written (PWS) | DSWSPW | Reports the average number of updates for each system page written during the sampling period The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
WIO | Write I/O Activity | DWIO | Reports the number of media manager write I/O requests during the sampling period Requests can batch-write I/O to allow multiple pages to be written per a single call to the media manager. The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
WKMAX | Max Workfiles Used Concurrently | DWKMAX | Reports the maximum number of work files in use during merge processing in the sampling period (QBSTWFM) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
WKNBF | Workfile Not Created–No Buffers | DWKNBF | Reports the number of work files that cannot be created because of insufficient buffer resources during the sampling period (QBSTMAX) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
WKPFZ | Workfile Prefetch Quantity Is Zero | DWKPFZ | Reports the number of work file sequential prefetches that did not occur because the dynamic prefetch quantity is zero during the sampling period (QBSTWKPD) The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |
WWP | Writes with Paging | DWWP | Reports the number of writes with paging during the sampling period The reported value is the number of times a buffer did not have real-storage frame backing when being PAGEFIXed to perform a write I/O. The counts in this view can be for the following buffer pools: BP0–BP49, BP8K–BP8K9, BP16K–BP16K9, BP32K–BP32K9, or all active pools. Parameters: [BP0–BP49|BP8K0–BP8K9| BP16K0–BP16K9|BP32K–BP32K9] |