Space Estimation report
The Space Estimation report, which is generated at the end of the utility run, provides statistics on space savings for segments, records, and blocks. The report summarizes the number of blocks saved and the percent of used DASD saved. One report is produced for each data set group in the database. For partitioned databases, one report covers all partitions, and the DSG field on the report is blank.
Other data which varies on the two reports is the information related to the root segment. The statistics for mean average record length before and after compression and the statistics related to blocks in the root area are only displayed for the primary data set group. If you have a partitioned database (HALDB or PDF), the statistics reflect mean average record length (before and after compression) and blocks in the root area for a single partition.
For HDAM databases, as shown in the following figure, the old HDAM parameters as specified in the DBD are given along with the suggested new HDAM parameters based on the percent of compression. These HDAM parameters appear only on the report for the primary data set group.
The following figure shows an example of the report using as input an image copy of a database that has not been compressed; in this case the data for EXPAND is left blank.
HD DSG SPACE ESTIMATION UTILITY REPORT
DATABASE HDAMSHOP TYPE HDAM ACCESS VSAM
DSG 01 LRECL 4089 BLOCKSIZE 4096
SAMPLE 100 PERCENT SKIP 0 BLOCKS
SEGMENT PRFX SEG SIZE <--- SEGMENT ---> SAMPLE <--- EXPAND ----> <---- COMPRESS ---->
NAME SC SIZE MIN MAX COUNT AV SIZE COUNT ROUTINE AV SIZE PCT TE-O AV SIZE PCT MS/FP AV SIZE PCT BYTES SAVED
LA7S01AA 01 34 218 325 4197 288.0 4197 ST G 80.1 72.1 83 86.0 70.1 847,419
ST NAME - LA7SHRTB (STAGE)
LA7S09AA 02 6 58 175 16132 158.0 16132 ST G 36.1 77.1 - 36.1 77.1 1,965,650
ST NAME - LA7SHRTB (RUN)
LA7S10AA 03 14 79 955 1129 328.6 1129 CH S 161.6 50.7 201 205.5 37.4 138,902
LA7S11AA 04 6 43 225 9779 212.7 9779 CH S 72.2 66.0 92 93.6 55.9 1,164,376
LA7S12AA 05 6 187 550 20 512.0 20 SH D 332.7 35.0 - 332.7 35.0 3,586
LA7S15AA 06 6 95 168 0 0.0 0
LA7S16AA 07 6 27 350 452 262.0 452 CH S 27.3 89.5 41 41.1 84.2 99,814
LA7S19AA 08 6 92 157 4192 106.0 4192 CH S 35.4 66.5 45 45.2 57.2 254,555
LA7S21AA 09 10 33 100 275 34.0 275 SH D 34.0 0.0 - 34.0 0.0 0
LA7S23AA 0A 6 9 100 274 100.0 274 CH S 15.9 84.0 21 22.3 77.6 21,273
LA7S24AA 0B 6 104 150 92 104.0 92 SH D 24.8 76.1 - 24.8 76.1 7,284
*TOTALS* 36542 36542 4,502,859
MEAN AVERAGE RECORD LENGTH BEFORE COMPRESSION - 1709.61
MEAN AVERAGE RECORD LENGTH AFTER COMPRESSION - 636.74
ROOT AREA OVERFLOW
TOTAL BLOCKS 601 1,197
AVAILABLE BLOCKS 0 0
AVAILABLE BLOCK BYTES 0 0
BLOCKS WITH FREE SPACE 510 1,114
FREE SPACE BLOCK BYTES 30,366 126,428
AVG FREE SPACE BLK BYTES 59 113
TOTAL FREE SPACE BYTES 30,366 126,428
************************************************************************************************************************************
* *
* TOTAL BLOCKS BEFORE COMPRESSION - - - 1,798 *
* TOTAL BLOCKS AFTER COMPRESSION - - - - - 697 *
* BLOCKS SAVED - - - - - - - - - - - - - 1,101 *
* *
* PERCENT OF USED DASD SAVED - - - - - - 61.23 *
* *
* *
* OLD HDAM RANDOMIZING PARAMETERS *
* *
* RMNAME=(DFSHDC40,1,600,) *
* *
* *
* NEW HDAM RANDOMIZING PARAMETERS *
* *
* RMNAME=(DFSHDC40,2,232,) *
* *
************************************************************************************************************************************
DATA PACKER/IMS (C) COPYRIGHT 2004 BMC SOFTWARE, INC. AS AN UNPUBLISHED WORK
The following figure shows an example of the report using an image copy of a compressed database; in this example the data for EXPAND is presented.
HD DSG SPACE ESTIMATION UTILITY REPORT
DATABASE TLC0D TYPE HDAM ACCESS OSAM
DSG 02 LRECL 6144 BLOCKSIZE 6144
SAMPLE 80 PERCENT SKIP 0 BLOCKS
SEGMENT PRFX SEG SIZE <--- SEGMENT ---> SAMPLE <--- EXPAND ----> <------------ COMPRESS ------------>
NAME SC SIZE MIN MAX COUNT AV SIZE COUNT ROUTINE AV SIZE PCT TE-O AV SIZE PCT MS/FP AV SIZE PCT BYTES SAVED
CB01AJR 03 2 - 126 910 83.8 864 DPKTLC 126.0 33.3 CH S 33.9 73.0 35 35.8 71.5 43,696
CB01AJS 04 6 - 56 9024 36.0 8572 DPKTLC 56.0 35.6 SH D 29.6 46.9 - 29.6 46.9 57,492
CB01AJU 06 6 - 70 8760 67.7 8325 DPKTLC 70.0 3.1 SH D 48.5 30.6 - 48.5 30.6 168,632
*TOTALS* 18694 17761 269,820
ROOT AREA OVERFLOW
TOTAL BLOCKS 182
AVAILABLE BLOCKS 0
AVAILABLE BLOCK BYTES 0
BLOCKS WITH FREE SPACE 164
FREE SPACE BLOCK BYTES 7,254
AVG FREE SPACE BLK BYTES 44
TOTAL FREE SPACE BYTES 7,254
***********************************************************************************************************************************
* *
* TOTAL BLOCKS BEFORE COMPRESSION - - - - 182 *
* TOTAL BLOCKS AFTER COMPRESSION - - - - - 139 *
* BLOCKS SAVED - - - - - - - - - - - - - - 43 *
* *
* PERCENT OF USED DASD SAVED - - - - - - 23.62 *
* *
***********************************************************************************************************************************
DATA PACKER/IMS (C) COPYRIGHT 2004 BMC SOFTWARE, INC. AS AN UNPUBLISHED WORK
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