Viewing the result of a simulation cycle
About this task
Results are named SIM <trace_file> <date> <time>, whereby SIM stands for Simulation, <trace_file> for the name of the trace data file that was used for the simulation, <date> and <time> for the date and time when the simulation started.
- If you want to delete results from the folder, select a specific
result by clicking it. Then press the Delete key. To delete all results,
right-click Results. Then click Delete
all. You are asked to confirm the deletion.
Note that results remain on the hard disk drive and take up space until they are deleted. They are usually located in folder C:\Documents and Settings \<userid> \db2pev<version> \simulation reports. However, because of their special format, do not manipulate the folder contents manually.
- To view the result from a simulation,
double-click it, or select it and press Enter. The result is shown in your web browser and contains the following information:
- A comparison of buffer pool efficiency for separate buffer pools
versus a single combined buffer pool, as function of the simulated
total buffer pool sizes.
Table 1. Example of simulation result, showing a comparison of buffer pool efficiency Separate Buffer Pools Combined Buffer Pool Total Pages Misses Application Hit Ratio Global Miss Ratio Misses Application Hit Ratio Global Miss Ratio 200 15332 14.9 83.7 92401 48.7 50.4 250 141398 21.5 77.2 35845 80.1 19.6 300 133484 25.9 72.8 24977 86.1 13.6 350 93542 48.1 51.0 23049 87.2 12.6 400® 43537 75.8 23.8 21780 87.9 11.9 450 31378 82.6 17.1 20891 88.4 11.4 500 23449 87.0 12.8 19977 88.9 10.9
- A list of recommended buffer pool sizes for the simulated buffer
pools, as function of the simulated total buffer pool sizes.
Table 2. Example of simulation result, showing a list of recommended buffer pool sizes Total Pages BP0 pages BP1 pages BP2 pages 150 50 50 50 200 100 50 50 250 50 50 150 300 50 50 200 350 100 50 200
- A detailed breakdown of efficiency by buffer pool operation for
each simulated buffer pool, as function of the simulated total buffer
Table 3. Example of simulation result, showing a detailed breakdown of efficiency All Random Sequential Prefetch List Prefetch Set write intent Buffer Pool Pages Total Misses Application Hit Ratio Misses % of Total Misses Misses % of Total Misses Misses % of Total Misses Misses % of Total Misses 50 24022 45.2 6269 26.1 14286 59.5 44 0.2 3423 14.2 100 15670 64.3 1833 11.7 13795 88.0 42 0.3 0 0.0 150 14563 66.8 1409 9.7 13112 90.0 42 0.3 0 0.0 200 10195 76.7 1160 11.4 8993 88.2 42 0.4 0 0.0 250 4080 90.7 955 23.4 3083 75.6 42 1.0 0 0.0 300 3516 92.0 719 20.4 2755 78.4 42 1.2 0 0.0 350 3018 93.1 467 15.5 2509 83.1 42 1.4 0 0.0
- Summaries of data collection details and simulation parameters, as they were used with this simulation. A summary of buffer pool activity counts, as found in the trace data file, and a summary of those counts resulting from a changed object to buffer pool assignment of this simulation.
- A table of object details. In this report section you can interactively
select for which simulated buffer pool and buffer pool size you want
to display the details of assigned objects. (This method avoids having
to scroll through a long list of details.) For the objects assigned
to the selected buffer pool the table shows object attributes, as
found in the trace data file, and selective buffer pool activity counts
resulting from the simulated buffer pool size.
In addition, this report section provides facilities to interactively sort the information in the table and to randomly search for specified information. See the actual report section header for instructions.
Table 4. Example of simulation result, showing a table of object details Name Type DB ID OB ID Trace buffer pool Trace entries Getpages Random misses Sequential misses List misses Setwrite misses Residency time DSNDB06.SYSGROUP TS 6 12 0 2 2 1 0 0 0 00:00:33 DSNDB06.SYSUSER TS 6 15 0 3 3 1 0 0 0 00:02:17 DSNDB06.DSNAPH01 IX 6 101 0 3 3 2 0 0 0 00:01:31
- The name of the object.
- The type of the object (table space or index space).
- DB ID
- The corresponding database ID.
- OB ID
- The object ID.
- Trace buffer pool
- The original buffer pool to which the object was assigned at the time trace data was collected.
- Trace entries
- The number of buffer pool activity entries in the trace data file for this object.
- The total number of Getpage requests (Random, Sequential, List) for this object.
- Random misses
- The number of misses of Getpage - Random requests for this object resulting from the simulated size.
- Sequential misses
- The number of misses of Getpage - Sequential requests for this object resulting from the simulated size.
- List misses
- The number of misses of Getpage - List requests for this object resulting from the simulated size.
- Setwrite misses
- The number of misses of Setwrite Intent requests for this object resulting from the simulated size.
- Residency time
- The average duration, in hours, minutes, and seconds, this object would be kept in the simulated buffer pool and size.
- A comparison of buffer pool efficiency for separate buffer pools versus a single combined buffer pool, as function of the simulated total buffer pool sizes.
- Use the hypertext links to navigate through the report.
You can open sections of the report by clicking Open this report in a new browser window.
Note especially the Click here to see more online help links. They provide detailed information about how to interpret the report.