Re: Raw Disk Partition vs. Unix File System (Oracle 6)

In article <CBuyrL.DLo_at_cbnewse.cb.att.com> cafe_at_cbnewse.cb.att.com (richard.dib) writes:

> We have a database in Oracle, and in order to speed it up we are
> considering moving it into a raw disk partition (Unix).
 

> Here are my questions:
 

> - Does anybody have any experience with Oracle using a raw disk
> partitition instead of the Unix file system? Could you share your
> experiences?

I have supported filesystem based Oracle 6 implementations and currently support raw device based Sybase 4. I miss the ease of administration of the filesystem based environment but Sybase does not write through the Unix file system as Oracle does. Using raw devices is such a pain. Unless you have no other choice my personal recommendation would be to stick with filesystem based implemenations.

Of course, much depends upon the volatility of your environment (growth, schema modifications, transaction rates). My particular situation was with ~800Mb databases with growth rates around 2-4% per month punctuated with occasional large spikes (up and down). Schema changes were made weekly and transaction rates were moderate with peaks during batch mode update and reporting cycles.

> - What are the benefits? Is the improvement in performance worth the
> work?

Oracle always claims there is a significant performance gain with raw devices but I was always able to achieve satisfactory performance with other tuning strategies. [ Oracle's own Tuning Guide points out that 80% of all performance gains are achieved in application design -- I found the extensive use of explain plan to be very helpful :-) ]

> - How easy would it be to backup this database? We are currently using
> a shell script to do this.

Backups should be unaffected (if I remember correctly).

> Thanks,
 

> Richard Dib AT&T BL
  Received on Mon Aug 16 1993 - 21:07:48 CEST