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Re: Weirdness with 'ons' process....

From: Alex Gorbachev <>
Date: Wed, 1 Nov 2006 00:08:07 -0500
Message-ID: <>


I don't know all the functioanlity that's implemented via ONS (aka Oracle Notification Services) but it's indeed related to FAN events and all that kitchen. It also involves listeners as they get notified of node up/down via ONS mechanism. I am not sure but I think that load balancing info get's propagated via ONS as well and etc.

Anyway, why would it be strange that connections are established from different source ports? (that's what you mean by 41,446 and ... 63,961?)

On 10/31/06, Bobak, Mark <> wrote:
> Hi,
> I'm running a 10gR2 ( 64-bit RAC cluster, three nodes on DL-585s
> (configured w/ 4 dual core CPUs and 32GB of RAM). I've been doing some
> fairly large-scale load testing, pointing our preproduction environment at
> this cluster, and seeing some great performance results.
> However, I've been seeing a weird anomaly on two of the three boxes. If I
> run:
> netstat -an|grep -c ":6101 "
> on each of the three nodes, one node reports zero, one reports 41,446 and
> one reports 63,961! These connections are all on the local loopback. Where
> are these coming from? I know (or I think I know) that this has to do with
> 'ons'. I haven't found much info on ONS.. I know it has to do with FAN,
> which I have not implemented at this point. Is this "normal"? If so, why
> the huge difference in distribution of the connections across nodes? (Oh,
> also, the status of these thousands of connections is 'TIME_WAIT'.)
> As this point, it doesn't seem to be negatively affecting performance, but
> it sure seems odd….anyone have any clues for me??
> AdvThanksance,
> -Mark
> --
> Mark J. Bobak
> Senior Oracle Architect
> ProQuest Information & Learning
> There is nothing so useless as doing efficiently that which shouldn't be
> done at all. –Peter F. Drucker, 1909-2005

Best regards,
Alex Gorbachev

The Pythian Group
Sr. Oracle DBA
Received on Tue Oct 31 2006 - 23:08:07 CST

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