Checkpoint not complete

[former_member84399]

Dear all,

After four Oracle 10 upgrades, the only remaining warning I have on db13 in all databases I upgraded is about "checkpoint not complete" . This only happens when there is a lot of activity in the database . It never happened before though, even when there was a lot of activity in the database.

I found note #79341 and #1068186 and I have set DISABLESELFTUNE_CHECKPOINTING

to FALSE, but this didn't particularly help, still get the warnings

My questions are:

The log buffer size is increased by the upgrade to 14M (instead of 1M that is used to be). I have 2 groups of redo log files, with 2 files each. Each file is 20M on size.

I was thinking of increasing them to 30M each. Do you think that this is a good thing to do?

Under /oracle/SID/saptrace/background, I see in the log writer trace the messages below. Do you know why I get these messages and are they relevant to the issue I have with the checkpoint?

• SERVICE NAME:() 2007-08-09 09:56:38.059

• SESSION ID:(316.1) 2007-08-09 09:56:38.059

Maximum redo generation record size = 197120 bytes

Maximum redo generation change vector size = 190204 bytes

tkcrrsarc: (WARN) Failed to find ARCH for message (message:0x10)

tkcrrpa: (WARN) Failed initial attempt to send ARCH message (message:0x10)

• 2007-08-09 12:55:29.062

LGWR: Archivelog for thread 1 sequence 3662 will NOT be compressed

• 2007-08-09 14:56:22.902

LGWR: Archivelog for thread 1 sequence 3663 will NOT be compressed

• 2007-08-09 15:09:29.136

LGWR: Archivelog for thread 1 sequence 3664 will NOT be compressed

• 2007-08-09 18:25:38.287

Many thanks

Andreas

[Former Member]

Hi Andreas,

I getting abit confuse. What I understand is that a checkpoint is issue whenever there is a log switch. My understanding of log switch is from log 11 to log 12 (assuming i had 4 log group 11 - 14 ). But base on your explanation, a checkpoint is issue when a complete switch log of group 11 to 12 to 13 to 14 then back to 11. Do highlight me if my understanding of the log switch theory is all the while wrong.

Regards

Lauran

[Former Member]

Hello,

I didn't write that. I only referred to one checkpoint because this was only relevant to the example I was trying to make. I will rephrase:

A checkpoint will happen in each log switch. 11 to 12, 12 to 13, 13 to 14, 14 to 11. These are 4 different checkpoints. If you have more redo log groups, redo log group 11 will be again in user after 12, 13 and 14 have been filled. Therefore, the database writer has more time to complete the checkpoint that was started when the switch from 11 to 12 took place.

When the dbwriter finishes with the 11 to 12 checkpoint, it can work on the other pending checkpoints (12 to 13, 13 to 14 etc etc )

I hope this clarifies

Andreas