Using IBM Informix Dynamic Server Version 12.10.FC13, on HP-UX ia64 , on a lab instance, I notice a strange behavior when using "ontape -a" to backup the logical logs to disk ( a file system directory visible by the informix instance ).
Onconfig:
LOGFILES 49
LOGSIZE 10000
DYNAMIC_LOGS 1
LOGBUFF 2048
LTAPEDEV /usr/informix/storage/volume33/backups/test_t
LTAPEBLK 20480
LTAPESIZE 204800000
When I do a "ontape -a" to do a backup of the logical logs to disk, I get the following type of files:
-rw-rw---- 1 informix informix 62914560 Sep 11 13:18 ajtixs06_30_Log0000002657
-rw-rw---- 1 informix informix 62914560 Sep 11 13:18 ajtixs06_30_Log0000002658
-rw-rw---- 1 informix informix 62914560 Sep 11 13:19 ajtixs06_30_Log0000002659
So, 60 MB files for 10 MB logical logs.
If I change LTAPEBLK to a smaller value, like 1024, with "ontape -a " I get the following files:
-rw-rw---- 1 informix informix 12582912 Sep 4 09:33 ajtixs06_30_Log0000002654
-rw-rw---- 1 informix informix 12582912 Sep 4 09:33 ajtixs06_30_Log0000002655
12 MB files for 10 MB logical logs.
If I once again change the LTAPEBLK to a smaller value, like 32 :
-rw-rw---- 1 informix informix 10420224 Aug 12 17:02 ajtixs06_30_Log0000002629
-rw-rw---- 1 informix informix 10420224 Aug 12 17:02 ajtixs06_30_Log0000002630
10 MB files for 10 MB logical logs.
I was under the impression that LTAPEBLK had no influence when doing backups to disk. But it seems to bloat the file sizes on disk.
Is this the expected behavior?
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Luis Marques
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#Informix