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Hello everyone,
Looking for some information on log_checkpoint_interval with respect to log switches.
This may be purely a complete misunderstanding on my part, but I think I am missing something here or I cannot find the appropriate documentation.
We have a database that is using 1 gig log files. and we are doing log switches/checkpoints _very_ frequently, in some cases in less than 10 minutes and in _most_ cases those log files are less than the full 1 gig, in fact they are considerablly less, in the area of 100-200m. We think this started after the recent upgrade to 8.0.6 but are not 100% sure.
To start with here are the parameters as we have them defined.
log_checkpoint_interval integer 60000000 log_checkpoint_timeout integer 0
From what I have read log_checkpoint_timout, and log_checkpoint_interval control checkpoints. Neither of which should force a log switch based on the documention.
Oracle seems to present conflicting information on this.
The analyst that handled the TAR i opened said that a checkpoint will force a log switch and the solution to slow the check points down was to raise log_checkpoint_interval to a number that could not be reached prior to the log filling up.
From what I understand log_checkpoint_interval is the number of OS blocks, 60M OS blocks is bigger than our log size. Obviously I am missing something here.
Looking at a post in Metalink, that oracle people replied to, what the analyst told me above is incorrect.
I guess my question comes down to this
Portion of v$archived_log
BLOCKS BLOCK_SIZE TO_CHAR(COMPLE
---------- ---------- --------------
460952 1024 10/30/00 10:27 1024000 1024 10/30/00 11:54 226364 1024 10/30/00 11:02 405973 1024 10/30/00 11:25
Portion of the alert log....
Mon Oct 30 10:55:58 2000
Beginning log switch checkpoint up to RBA [0x6a1.2.10], SCN:
0x0000.64cf083a
Thread 1 advanced to log sequence 1697
Current log# 4 seq# 1697 mem# 0: /u16/oradata/P013/redo4aP013.log
Current log# 4 seq# 1697 mem# 1: /u17/oradata/P013/redo4bP013.log
Mon Oct 30 11:02:11 2000
Beginning log switch checkpoint up to RBA [0x6a2.2.10], SCN:
0x0000.64cf15d5
Thread 1 advanced to log sequence 1698
Current log# 5 seq# 1698 mem# 0: /u17/oradata/P013/redo5aP013.log
Current log# 5 seq# 1698 mem# 1: /u18/oradata/P013/redo5bP013.log
Received on Mon Oct 30 2000 - 12:05:17 CST