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Message Posted: Thu, 10 Jul 2003 @ 12:28:48 GMT

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Hi Ruth,

Couple of things.

Teradata does 'session balancing' across the PE's, not workload balancing. In most cases this is not an issue as the PE's usually don't place a heavy load on the system. In the scenario that you outlined (which I accept is purely for illustration) then yes you'll probably find that one node being driven harder by the PE's.

As part of the connection process to Teradata, the tdp/mtdp software will session balance within the PE's defined for the Logicalhostid, not "every PE in the system". Thus if the Teradata system is connected to both an IBM m/f and the lan, there will be two logicalhostid's. If a user connects from the lan, they can only logon to one the PE's defined to the 'lan' logicalhostids. The session balancing algorithm does not take into account node types, connection types etc, it simply looks at each PE within the logicahostid.

I'm not really sure there's any difference between a 'lan connection' and a 'unix connection' - unless you have PE's defined to different logical hostids.

You're correct in that (with the scenario outlined above) which PE a session is connected to will not affect Teradata's parallelism. That is more to do with the running of the sql requests rather than which PE they came from.

Does this take you forward?

Cheers,

Dave

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