reference comparision

Lennart Ohman <>
Sun Aug 27 17:07:19 CEST 2006


Hi, the answer is no.

Pids, references and alike has a local unique component and
a "node-pointer". The "node-pointer" tells a node (having
received for instance a reference from another node) on which node
this reference really exists. So any node can compare two references
and instantly conclude if they are equal or not.
I do however not know how greater or less comparisons will work
out. That is if the order will be done on node name (meaning
that two references will always be sorted the same way regardless
on which node the comparison is made), or if comparison will be
made on the "node-pointer" which may very well be a numerically
different number on two different nodes (having received the
references from a third node).
One can on the other hand discus the relevance of doing > and <
comparisons on a reference...

Best Regards,
Lennart


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> -----Original Message-----
> From:  [mailto:owner-erlang-
> ] On Behalf Of Thomas Raes
> Sent: Saturday, August 26, 2006 5:08 PM
> To: 
> Subject: reference comparision
> 
> Hello,
> 
> Does comparing references create network traffic to the nodes where the
> references were created?
> If so, has anybody an idea how this can be avoided in order to reduce
> communication overhead between nodes?
> 
> Best regards,
> 
> Thomas






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