Re: Multiple RBS tablespaces

The issue is not one of I/O contention, but of segment header contention -if you've got 100 people trying to do OLTP-type transactions, and they're all fighting over access to the one rollback segment, you can expect Oracle to be forced to have to queue them up behind each other.

The usual rule of thumb is that to get round this contention issue, there should be 1 rollback segment per every 4 concurrent transactions. And it really won't matter too much if they are all sitting on the one disk: contention for the segment header would make i/o contention look like a children's picnic.

Regards
HJR

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<gorgos_at_my-deja.com> wrote in message news:8v0la7$705$1_at_nnrp1.deja.com...


> Hello again,

> a colleague of mine was suggesting that multiple rollback segment

> tablespaces was good.  If the tablespaces are on seperate disks, I can

> understand that IO contention will be reduced, but if they're on the

> same disk and don't see the benefit.  Am I missing the point here ??

>

> Thanks

>

>

> Sent via Deja.com http://www.deja.com/

> Before you buy.