Re: Understanding Oracle blocks and UNIX blocks re. redos

From: Dave Bottom <dlbottom_at_ime.net>
Date: 2000/03/30
Message-ID: <W_JE4.1249$O2.23310@harpo>#1/1

Sybrand Bakker <postbus_at_sybrandb.demon.nl> wrote in message news:953916155.15010.2.pluto.d4ee154e_at_news.demon.nl...
> Yes, to add something...
> Suppose the block size of the OS (or disk volume) is 8k.
> Oracle requests 2k in an ordinary I/O request.
> This will result in the O/S reading 8k anyway.
> Hence the block size of Oracle should always be a multiple (1 or greater)
of
> the O/S blocksize.
>
> Regards,
>
> Sybrand Bakker, Oracle DBA

From personal experience on HP-UX systems if you do NOT make the oracle block size at least 1X the OS block size you will kill your performance. We did this with a PeopleSoft database, set Oracle to 4K with UX running 8K blocks and instantly had 100% disk utilization on all the data disks and abysmal performance.

Dave, Unix sys admin and newbie Oracle DBA Received on Thu Mar 30 2000 - 00:00:00 CST