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Issues from the Spec Steve Fisher / RAL. JRA1-UK Meeting 5 July 2004, Abingdon, UK. www.eu-egee.org. EGEE is a project funded by the European Union under contract IST-2003-508833. Contents. Too many times DataBaseProducer. Times. Times associated with a PrimaryProducer
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Issues from the SpecSteve Fisher / RAL JRA1-UK Meeting 5 July 2004, Abingdon, UK www.eu-egee.org EGEE is a project funded by the European Union under contract IST-2003-508833
Contents • Too many times • DataBaseProducer
Times • Times associated with a PrimaryProducer • When data will be removed (to save space) • Extra time to keep info if Consumer is going slow • When it expects to publish again (related to intuitive concept of latest) • Note it could be the same producer or a new one • The GRRP time out • How long data will be kept after producer closes • How long data will be kept after undeclare table
Proposal • Associate just 2 times with a PrimaryProducer: LatestRP and HistoryRP • LatestRP • is published with all tuples • data are held after close for this time • data are held after undeclare for this time • Is used for the GRRP time out • HistoryRP • data discarded after this time but a new flag SignalSlowConsumer, if set, will cause further inserts to generate an error, and data are not discarded • Physically all data are held for the same period in the Producer but Latest Queries by default look back by the published MinRP
Proposal for Secondaries • Associate same 2 times with a SecondaryProducer • close and undeclare take effect immediately • LatestRP is associated with each tuple as set by the original PrimaryProducer • TerminationInterval • Is used for the GRRP time out • HistoryRP • data discarded after this time but a new flag SignalSlowConsumer, if set, will stop the data streaming in. This will eventually lead to a message from an insert to the PrimaryProducers and a refusal to accept more data at source • Physically all data are held for the same period in the Producer but Latest Queries by default look back by the published LatestRP associated with the published tuple
DataBaseProducer • Do we want to bring back a way of publishing via an existing database? • If DB has our structure we could just use it and pretend it is a PrimaryProducer • Is their a benefit in allowing people to publish any old table? • It will only do one kind of query – like latest but people could fudge it if the schema had a time field • maybe the one query it supports should not be continuous, history or latest but just call it a database query • no retention periods • needs a GRRP though • Probably needs more thought • Would be a good way to work with GridICE perhaps