Requesting table space maintenance recommendations
Db2® Admin Tool can use data from the real-time statistics (RTS) tables to provide recommendations on when to run certain maintenance functions, such as COPY, REORG, or RUNSTATS, on your table spaces.
Before you begin
To get these table space recommendations, real-time statistics tables must exist.
Procedure
To request table space maintenance recommendations:
- On the DB2 Administration Menu (ADB2) panel, specify option 3, and press Enter.
- On the DB2 Performance Queries (ADB23) panel, specify option 14, and press Enter.
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On the Input Parameters for Real-Time Statistics (ADB2314T) panel, specify your own values for the fields or use the system
default values, and press Enter.
These values are used to calculate recommendations that can help you to determine when to run certain maintenance functions or when to enlarge your Db2 data sets.
Important: The recommendations that Db2 Admin Tool provides are based on general formulas and might not apply or be accurate for every installation. Additionally, if the real-time statistics tables contain only a small portion of information about your Db2 subsystem, the recommendations might not apply to the entire subsystem.To reset all user values to the system default values, issue the RESET primary command, and press Enter.
Figure 1. Input Parameters for Real-Time Statistics (ADB2314T) panel DB2 Admin -------- DB2X Input Parameters for Real-Time Statistics ------- 09:39 Option ===> The input values specified below are used in the calculations which determine the recommended table space actions. For a full description of any parameter, use panel HELP and refer to the entry indicated by the parenthesized keyword. Run using default settings . . (Yes/No) (default) More: + Limit, number of physical extents . . . . . . . . (50) (ExtentLimit) Limit, number of days since last image copy . . . (7) (CRDaySncLastCopy) Ratio, as percent, of updated pages to preformatted pages in table space or partition . . . . . . . (1) (CRUpdatedPagesPct) Ratio, as percent, of distinct updated pages to total active pages since last image copy . . . . (1) (ICRUpdatedPagesPct) Ratio, as percent, of INSERTs, UPDATEs, DELETEs to total rows or LOBs since last full image copy . (10) (CRChangesPct) Ratio, as percent, of INSERTs, UPDATEs, DELETEs to total rows or LOBs since last incremental image copy . . . . . . . . . . . . . . . . . . . . . . (1) (ICRChangesPct) Ratio, as percent, of INSERTs to total rows or LOBs since last REORG . . . . . . . . . . . . . . . . (25) (RRTInsertsPct) Ratio, as percent, of DELETEs to total rows or LOBs since last REORG . . . . . . . . . . . . . . . . (25) (RRTDeletesPct) Ratio, as percent, of unclustered INSERTs to total rows or LOBs . . . . . . . . . . . . . . . (10) (RRTUnclustInsPct) Ratio, as percent, of imperfectly chunked LOBs to total rows or LOBS . . . . . . . . . . . . . . . (10) (RRTDisorgLOBPct) Ratio, as percent, of overflow records to total of rows or LOBs since last REORG or LOAD REPLACE. . (10) (RRTIndRefLimit) Limit, number of mass deletes or dropped tables since last REORG or LOAD REPLACE . . . . . . . . (0) (RRTMassDelLimit) Ratio, as percent, of the space allocated to the actual space used. . . . . . . . . . . . . . . . (-1) (RRTDataSpaceRat) Ratio, as percent, of INSERTs, UPDATEs, DELETEs to total rows or LOBs since last RUNSTATS. . . . (20) (SRTInsDelUpdPct) Limit, sum of INSERTs, UPDATEs, DELETEs since last RUNSTATS . . . . . . . . . . . . . . . . . (0) (SRTInsDelUpdAbs) Limit, number of mass deletes since last REORG or LOAD REPLACE . . . . . . . . . . . . . . . . (0) (SRTMassDelLimit)When you press Enter, recommendations are displayed, as shown in the following example Table Space Maintenance (ADB2314) panel:
Figure 2. Table Space Maintenance (ADB2314) panel, which is the result of panel ADB2314T ADB2314 n ---------- DB2X Table Space Maintenance ------- Row 1 to 31 of 1,000 Command ===> ________________________________________________ Scroll ===> PAGE Commands: COPY INCCOPY REORG RUNSTATS COPYALL INCCOPYALL REORGALL RUNSTATSALL REFRTS Line commands: C - Full Copy CI - Inc Copy O - Reorg R - Runstats AL - Resize S - Select I - Interpret ? - Show all line commands Pct Num <---Recommendations---> Sel TSname DBname Part Space(KB) Used Ext Copy Reorg Runst Resize * * * ___________ * * * * * * --- -------- -------- ------ ----------- ---- ------ ---- ----- ----- ------ ___ DSN8S91E DSN8D91A 1400 ? ? ? FUL YES YES NO ___ XPUR0000 DSN8D91X 0 720 100 1 FUL YES YES NO ___ XSUP0000 DSN8D91X 0 720 100 1 FUL YES YES NO ___ DSQTSRDO DSQDBCTL 0 48 100 1 FUL YES YES NO ___ LI6510TS VNDS148 1 48 100 1 FUL YES YES NO ___ LI6510TS VNDS148 2 48 100 1 FUL YES YES NO ___ LI6510TS VNDS148 3 48 100 1 FUL YES YES NO ___ LI6510TS VNDS148 4 48 100 1 FUL YES YES NO ___ ARCHIVE1 DBADD101 0 48 100 1 FUL YES YES NO ___ RETRIEV1 DBADD101 0 48 100 1 FUL YES YES NO