Working with FDRQUERY
The ABR statistics query program (FDRQUERY) has been specifically designed to produce DUMP statistics as if a user were backing up DASD volumes with FDR or with FDRABR using TYPE=ABR. Also you can request how many data sets would be archived by FDRABR using last reference date groupings.
Backup simulation
The FDR statistics query program scans all of the volumes specified comparing the number of tracks that would be dumped if FDR were to execute against the volume as compared to ABR dumping only data sets that have the update indicator. The saving is printed in tracks and percentage. Since ABR is usually run every day, the query program does not report on any data set with an update indicator if it has not been referenced in the last two days. Even using this technique, the query program may indicate that a larger number of data sets are dumped by ABR than would actually take place, if the update indicator is on but the data set was only read in the last two days.
Archive simulation
The FDRstatistics query program can scan all of the volumes specified to report on the number of data sets and the tracks they occupy, grouped by the last time they were referenced. As a default, the query program reports data sets in 30 day groups. The purpose of this report is to show an FDR user how much DASD space could be saved, if ABR were used to archive off data sets that have not been referenced in a specific period of time.
Sample archive report
This is a sample Archive Report.
VOLSER DEVTYPE TRACKS %ALLOC %ALLOC DAYS DATE DSNS TRACKS %SAVED
IDPT01 3390-9 95213 63.36% 12.25% 30 2014190 594 76799 80.66%
The report fields are:
- ALLOC TRACKS - This number represents the total currently allocated tracks.
- BEFORE %ALLOC - This number is the percentage of the volume that is in use. It is the number of tracks allocated, divided by the total number of tracks on the DASD volume. For example, volume IDPT01 (a 3390-9 DASD) contains 150,255 tracks of which 95,213 tracks are allocated. The “BEFORE % ALLOC” is 63.36%
. - AFTER %ALLOC - This field represents the percent allocated the volume is if you archive data sets that have not been used for the number of days specified in the next column. For example, if on IDPT01, there are 594 data sets with 76,799 tracks that have not been referenced in 30 days and you archive them, the “AFTER % ALLOC” is 12.25%.
95,213 | – | 76,799 | = | 18,414 | / | 150,255 | = | 12.25% |
|---|---|---|---|---|---|---|---|---|
Allocated Tracks | Archived Tracks | Tracks after Archiving | Number of Tracks | After% ALLOC |
- LAST USED - The “DAYS” field shows the number of days used to calculate this line in the report. The data sets on this line have not been used for this number of days. The “DATE” field shows the corresponding Julian date (today’s date minus “DAYS”).
- SAVINGS IF ARCHIVED - These fields show the number of data sets that would be archived, the number of tracks allocated to those data sets and the percentage of the total allocated tracks they represent.
For example, if volume IDPT01 has 95,213 tracks allocated and you archive 76799 tracks, the “% SAVED” is 80.66% (76,799 ÷ 95,213 = 80.66%). This means that 80.66% of the allocated space would be freed by ARCHIVING.
This section contains the following topics: