log groups,'checkpoint not complete ' error

[mkey]

Hi all,

I have 3 log group and the size is 1024K. Now the database is experiancing performance issue. Also in the log file I see the 'checkpoint not complete ' error. So I want to add more log groups.
The script look something like this:


ALTER DATABASE ADD LOGFILE GROUP 6 ('D:\ORANT8\ORADATA\INPUT\redo06.log','F:\ORADATA8\INPUT\redo0602.log')
size 1024K;

The should the new group size be bigger? Also can I create three new groups and delete the existing once? Is that safe things to do?

Thanks!

 

[did02]

Hi,

The sizing of redolog files depends on your system, archive mode,... (see oracle doc). redolog files = 10 Mo is not very big. so I think you can increase it.

Moreover, operations on redolog is safe and not too complicated (could be done with an open database). ALTER DATABASE system privilege is needed.

If you create 3 new groups and then try to delete the old one, you will not be able to drop the active group.
So you have to switch the group file :

ALTER SYSTEM SWITCH LOGFILE;

Then the following request allows you to check the active group:

select a.GROUP#,substr(b.MEMBER,1,50),a.MEMBERS,a.STATUS
from V$LOG a,V$LOGFILE b
order by 1,2;

Hope it helps you.
Rgds,
Did02

 

[cgswong]

Create larger redo logs (don't know your environment but I'd go about 15MB) and increase the groups to about 5. Delete the old logs (all logs should be the same size) but as Did02 said, you'll have to do a log switch to delete the active log. Also may try increasing the LOG_BUFFER size.

If you still get the message you will need to either further increase the size of the redo logs or create more redo log groups.

Hope this helps. The ONE ( HP-UX + Solaris + AIX + Tru64 = Unix)