DAB CACHE report

This report supplies information on the subareas or files served by a DAB cache.

Report output

The DAB CACHE report is output only at the explicit request of the SM2 user by means of the SELECT-DAB-CACHE statement. After this statement has been entered, the user receives not only the DAB report, but also the DAB CACHE report for the DAB caches he or she has selected.

The DAB CACHE report provides detailed information on the subareas or files served by DAB.

Overflow screens may be requested for this report.
The monitored data output is sorted under the categories READ and WRITE.It is possible to output information on up to 16 DAB caches.

 HOST0001 SM2 DAB CACHE           CYCLE:   60 S                   <date>  <time>

 ID: MMRD#SHPUB                       MOD: R      MED:MM SIZE(FIX):  250.0 MB

    VSN / FILE      | FIRST-HP, LAST-HP   |S| READ  |RD-HIT| WRITE |WR-HIT|OVER 
                    |                     | | (1/S) | (%)  | (1/S) | (%)  |(1/S)
 -------------------+---------------------+-+-------+------+-------+------+-----
 *SUMMARY           |         1-         1| |   0.0 |  0.0 |   0.0 |  0.0 | 0.0 
 -------------------+---------------------+-+-------+------+-------+------+-----

Monitoring information

ID	Name of the appropriate DAB cache as selected via the ADD-CACHE-ID operand of the SELECT-DAB-CACHE statement.
MOD	Cache mode
R	The cache is used as a read cache.
W	The cache is used as a write cache.
W/R	The cache is used as a read/write cache.
PFA	The cache is used as a PFA cache.
In the case of the R/W, W and PFA modes, the Force Out parameter is also specified. This indicates whether and at what fill level data written to the cache should be written back to the external data volumes.
N	Data is not written back (No)
L	Low fill level
H	High fill level
MED	Cache medium
MM	Main memory
SIZE(FIX) SIZE(VAR)	Size of the DAB cache. This can be fixed (FIX) or variable (VAR). In the case of (VAR), the size at the time of data acquisition is output.
Each line in this report contains data on the different subareas or files served by the cache with the specified CACHE-ID. The individual columns contain the following data:
VSN / FILE	VSN of the volume containing the subarea or, if DAB supports a file, the name of the file containing the subarea. If there is more than one subarea on the same volume or in the same file, these subareas are listed in successive lines. The relevant VSN or file name can be found only in the first line of this list. If the file name is longer than 21 characters, it is truncated on the right.
FIRST-HP,LAST-HP	First and last physical block numbers of the subarea, if a volume is listed in column 1. First and last logical block numbers of the subarea, if a file name is listed in column 1.
S	Any subarea which was not served during the last monitoring cycle is marked with an asterisk (*) in this column (S = served). No data is output for this subarea.

The columns READ, RD-HIT, WRITE, WR-HIT and OVER have the same meaning as in the DAB report. However, the information they contain refers to individual subareas or files and not to the DAB cache as a whole.

In order to reduce the amount of data recorded, the following applies to the DAB-CACHE report when AutoDAB is used:

If the cache is created with AREA=*BY-SYSTEM(ADM-PFA) or with CACHED-FILES=*BY-SYSTEM(USER-PFA), the output does not include a list of the files served. Instead, it contains a summary of the entire cache. The (VSN/FILE=*SUMMARY) row of the DAB CACHE report thus contains the same data as the DAB report. As a result, the information in the FIRST-HP, LAST-HP column is irrelevant.

Monitored data on the files served by the cache can be output using the DAB statement SHOW-DAB-CACHING CACHE-ID=*ALL, INF=*SYSTEM-CACHED-FILES (CACHING=*ACTIVE).