# Delta Save merge block counts vs PLOG copy DSIM block counts **URL:** \ **Category:** Forum\ **Tags:** Adabas-Natural, Adabas, Adabas-on-Mainframes\ **Created:** [April 21, 2022, 12:55pm UTC](https://techcommunity.softwareag.com/t/delta-save-merge-block-counts-vs-plog-copy-dsim-block-counts/256892 "2022-04-21T12:55:23Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![Brian\_Johnson1](https://sea1.discourse-cdn.com/techcommunity/user_avatar/techcommunity.softwareag.com/brian_johnson1/32/163_2.png) [@Brian\_Johnson1](https://techcommunity.softwareag.com/u/Brian_Johnson1)\ **Post date:** [April 21, 2022, 12:55pm UTC](https://techcommunity.softwareag.com/t/delta-save-merge-block-counts-vs-plog-copy-dsim-block-counts/256892/1 "2022-04-21T12:55:23Z")
We are running ADA851, ADE851 and AZP851 on a z/OS 2.1 IBM environment. I just noticed this, but I have not had any issues on the occasions where I have ever restored from Delta Save-driven weekly’s and delta merges. When the PLOG flips after performing an online Delta Save operation, the PLOG copy includes statistics of the Delta Save image (DSIM) blocks encountered between the SYN1 and SYN2 checkpoints as the example below: ## Parameters: ADARES PLCOPY OPENOUT ADARES DSIMSIZE=6400 DSF031 SYN1 Checkpoint encountered on Protection Log PLOGNUM = 207 BLOCKNUM = 2420333 DSF032 SYN2 Checkpoint encountered on Protection Log PLOGNUM = 207 BLOCKNUM = 2420388 DSF039 DSIM Dataset completed ``` DSIM Dataset Statistics: 0% Full 123 ASSO Block Images Written 51 DATA Block Images Written 0 New AC Blocks Recorded ``` Then when the Delta merge is performed later, when including the DSIM data in the merge process, it includes stats about that: ## Parameters: ADASAV MERGE PATTERN=‘DD’ ADASAV DSIMDEV=8391 DSF045 Input OFFLINE DELTA Save tape opened DSID = 1 / 1171 - 1173 / 2022-04-19 23:01:27 DSF045 Input ONLINE DELTA Save tape opened DSID = 1 / 1174 - 1174 / 2022-04-20 23:01:28 DSF049 DSIM Dataset statistics: ``` 107 ASSO Blocks present 35 DATA Blocks present ``` DSF047 Output OFFLINE DELTA Save tape completed DSID = 1 / 1171 - 1174 / 2022-04-20 23:01:28 I find it odd that the DSIM ASSO & DATA block counts from the PLOG copy process do not match the block counts from the Delta merge process. Should I be concerned about the integrity of the delta merges and by inference the full offline DB save equivalent since for so long it has been driven by Delta Saves, daily merges and weekly merges (as is evidenced by the fact my DSID is 1 / 1171-1174)? Regards, Brian Johnson ---
**Author:** ![Bjarne\_Soerensen3](https://avatars.discourse-cdn.com/v4/letter/b/85e7bf/32.png) [@Bjarne\_Soerensen3](https://techcommunity.softwareag.com/u/Bjarne_Soerensen3)\ **Post date:** [May 24, 2022, 10:13am UTC](https://techcommunity.softwareag.com/t/delta-save-merge-block-counts-vs-plog-copy-dsim-block-counts/256892/2 "2022-05-24T10:13:29Z")
An likely explanation could be that the same RABN’s are written repeatedly to DSIM - that EG. DS block 4711 is written and then overwritten a number of times on the DSIM. Check that the “blocks present” are always less than or equal to “Images written”. ---
**Author:** ![system](https://global.discourse-cdn.com/techcommunity/original/3X/c/d/cd19967bb605d28a72d77eb83a1cae22f3df2eb8.svg) [@system](https://techcommunity.softwareag.com/u/system)\ **Post date:** [August 22, 2022, 10:13am UTC](https://techcommunity.softwareag.com/t/delta-save-merge-block-counts-vs-plog-copy-dsim-block-counts/256892/3 "2022-08-22T10:13:40Z")
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