Re: Redo block size...

> > > How do I find out the chunk size in which redo information is written
> > > to disk?
> >
> > Oracle 9.2.0.3.0 on RedHat 8.0.
> > Extfs3 filesystems, 4KB for datafile volumes.
> >
> > SQL> select distinct block_size from v$archived_log;
> >
> > BLOCK_SIZE
> > ----------
> > 512
> Is the same for me. Ok, I guess it's kinda hard to distribute that across
> two disks.

In case you're not running in archivelog mode, you can still check the redo logfile block size with $ORACLE_HOME/bin/dbfsize:

$ dbfsize redo02.log

Database file: redo02.log
Database file type: raw device
Database file size: 819200 512 byte blocks $ uname -a
SunOS <host> 5.8 Generic_108528-10 sun4u sparc SUNW,Ultra-80

In addition to block size, it also tells you if the file is filesystem-based. In my case, it's using Veritas Quick I/O but reported as raw.

Most OSes use 512 bytes as logfile block size. But HPUX uses 1k, probably DEV_BSIZE defined in /usr/include/sys/param.h. This size is actually not filesystem dependent.

Yong Huang Received on Sun Jan 25 2004 - 16:43:06 CST