LHC Computer Grid - Rollout
> [mailto:[log in to unmask]] On Behalf Of David Smith said:
> The number of queries that the broker makes to the BDII per
> job depends on
> whether the job's JDL includes any attributes for which the
> broker has to
> query the 'GlueSubCluster' record - eg.
> 'GlueHostApplicationSoftwareRunTimeEnvironment' or
> 'GlueHostBenchmarkSI00'. If the SubCluster record is needed
> the number of
> queries is large, one for each sub cluster (although maybe it's worth
> noting the queries are all done on one connection). Together with the
> slower response meant that some jobs were taking several
> minutes to match.
I don't really understand that, in LCG there is only ever one subcluster per
CE so you should only need one extra query, i.e. one to get the CE
information and another to get the subcluster. In fact since several CEs
usually share the same subcluster the factor could be quite a bit less than
2 if the code checked to see if it already had the information.
Stephen
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