Re: external storage and commit?

From: Sean M <smckeownNO_at_BACKSIESearthlink.net>
Date: Mon, 15 Apr 2002 11:18:03 -0600
Message-ID: <3CBB0B4B.72A12330@BACKSIESearthlink.net>

Sybrand Bakker wrote:
>
> Generally speaking any O/S caching should be turned off or limited as
> much as possible.

Maybe so, but what he's talking about isn't OS caching. It's disk subsystem caching using non-volitile RAM (i.e. RAM w/a battery backup in case of power failure, etc.). A write to the cache, as far as the host's OS is concerned (and therefore as far as Oracle is concerned) is as good as a write to actual hard disk.

> All transactions are protected using the online redo log, and of
> course you run in archivelog, and you don't have all your database
> files (and definitely not the online redologs) on such a device.

No. Such a device (I don't have direct experience with the IBM ESS hardware, but from what I've read it's very similar in concept to EMC storage arrays) is perfectly suitable for all Oracle files, including datafiles, online/archived redos, code trees, controlfiles, everything.

Regards,
Sean Received on Mon Apr 15 2002 - 12:18:03 CDT