Re: How to "Defragment" Tablespaces ?

On Mon, 09 Apr 2001 18:38:59 +0800, Connor McDonald <connor_mcdonald_at_yahoo.com> wrote:

>
>As further reinforcement you can see a 'bug' on Metalink where a large
>Oracle user (who I happened to be working for at the time) got massively
>hit by "performance problems" when upgrading to 8i - and NONE of the
>explain plans had changed...the reason was due to a change in the calls
>made to the underlying disks (in a veritas file system) which brought
>the database to a standstill on internal locking issues (a variant on
>inode locks)...the only fix was to not use vxfs file systems (by moving
>to quick io)...
>
>Another reason I prefer to use raw on locally managed tspaces..
>

Thanks for the tip. I tend to rely very little on all these third-party "extensions" to I/O.

It's been my experience what I spend in time and money researching the right combination of fixes/patches for the OS/ORACLE/3rdparty, phase of the moon and wind direction to get the whole she-bang to work as a team is simply not worth the trouble.
Been at the sticky end of too many "weird problems" to believe in it...

Much better to stick to tried and true: raw. At least, I have some degree of control over what the heck is being done between the time I put the ";" in the DML and the time the disk goes "clunck".

And nowadays with LVMs, config/admin of raw is child's play compared to the bad old days. I must admit however I have a soft spot for those EMC things: they can be darn fast! ;-)

Cheers
Nuno Souto
nsouto_at_bigpond.net.au.nospam
http://www.users.bigpond.net.au/the_Den/index.html Received on Tue Apr 10 2001 - 03:25:26 CDT