Re: How to resize redo logs

Thank you guys for the tips, but I still not sure how to resize a redo log files.

just to be clear I am talking about the redo log files.

My redo log file is 1 meg in size and I want to increase it to 5 meg.

Thanks
Mo

> You can also query the database to determine how often the redo logs
> are switching. There are several flavors of the script below, but this
> one will calculate the average log switches per day.
>
> -- avg redo switches per day
> select round(avg(count(*)))
> from v$loghist
> group by to_char(first_time,'J');
>
> mreeves
>
> On Fri, 2 Feb 2001 08:02:13 +1100, "Howard J. Rogers"
> <howardjr_at_www.com> wrote:
>
> >They should be as big as are needed to get log switches happening at the
> >"right" interval.
> >
> >Huge log files will take ages to fill, and you will therefore log switch
> >infrequently. Since there is a major checkpoint at each log switch, that
> >means you avoid having one hell of an i/o fest. Performance therefore goes
> >up a bit. Since Instance Recovery means Oracle replays all transactions
> >since the last checkpoint, however, then huge log files mean longer Instance
> >Recoveries.
> >
> >Tiny log files will fill rapidly, and will therefore switch like crazy -lots
> >of checkpoints, poor performance, but good Instance Recovery times.
> >
> >Your mission is to find somewhere along that spectrum where you can be
> >happy. The usual 'rule of thumb' that a lot of DBAs adopt is to arrange for
> >the files to be big enough that they switch every half-hour to an hour, on
> >average. But that may well not be what is suitable in your particular case.
> >
> >You can check how often you are log switching by checking the Alert Log.
> >Messages such as "Thread 1 advanced to Log Sequence 15634" indicate a log
> >switch.
> >
> >If you ever see a message to the effect that "Thread 1 unable to advance to
> >Log Sequence 15635", then it means you haven't got *enough* redo log groups
> >(the size of them having little or no bearing on that particular message).
> >
> >Regards
> >HJR
> >
> >
> ><MAbbouchi_at_IITRI.ORG> wrote in message
> >news:DD42667CBCE4D3119D0700104B95123F3016CA_at_abmail.iitri.org...
> >> How to resize redo logs and is there a special consideration to be aware
 of?
> >>
> >> Thanks
> >> Mo
> >>
> >> --
> >> Posted from nat05.IITRI.ORG [205.167.170.5]
> >> via Mailgate.ORG Server - http://www.Mailgate.ORG
> >
> >
Received on Thu Feb 01 2001 - 18:14:46 CST