As far as n-way communications are concerned it doesn't get worse than 3.Node A (who wants a particular resource) asks Node B (who is the master for the resource) to tell Node C (who is currently exclusive owner of the resource) to pass it to Node A
It doesn't matter how many nodes there are, the loop is always a triangle. On the other hand, the fewer nodes you have the more likely you are to be themaster of a particular resource (no N-way negotiation), and the more likely that the master also happens to be the owner if you aren't the master (better
chance of 2-way rather than 3 way). Regards Jonathan Lewis http://jonathanlewis.wordpress.com----- Original Message ----- From: "Guillermo Alan Bort" <cicciuxdba@xxxxxxxxx>
To: "oracle-l-freelists" <oracle-l@xxxxxxxxxxxxx> Sent: Thursday, June 09, 2011 3:51 PM Subject: 3 or 4 nodes in a RAC?
List This is a design question.... We are building a new RAC, we currently have a 4 node RAC and we are upgrading the hardware and software and are wondering whether to go with a 3 node RAC or a 4 node RAC. I've heard rumors that 3node RAC perform better (we have no 4-way current gc waits, but there are a lot of 3-way current waits)... So, what I'm looking for is links or experiences regarding 3-way and 4-way RACs. Thanks in advance Alan.- ----- No virus found in this message. Checked by AVG - www.avg.com Version: 10.0.1382 / Virus Database: 1511/3689 - Release Date: 06/08/11
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