Re: Redo block size...

From: Noons <wizofoz2k_at_yahoo.com.au>
Date: Mon, 26 Jan 2004 12:48:29 +1100
Message-ID: <401471f0$3$19709$afc38c87@news.optusnet.com.au>

"Yong Huang" <yong321_at_yahoo.com> wrote in message news:b3cb12d6.0401251443.e217f7b_at_posting.google.com...

> filesystem-based. In my case, it's using Veritas Quick I/O but
> reported as raw.

That would be because the partition is managed by Veritas itself from a Unix raw partition?

> 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.

Actually, if the redo log file is in a file system, write size is totally dependent on it. If you request a write of 512 bytes in a file system of 4K block size, the OS *will* write 4K. Like it or not...

And the main reason for the usual recomendation to keep redo log in raw.

-- 
Cheers
Nuno Souto
wizofoz2k_at_yahoo.com.au.nspam

Received on Sun Jan 25 2004 - 19:48:29 CST