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QV Server Scheduling Clarification-Different Scenario

Hello

I have another scenario to one of my previous qv server questions

I have a Parent QVD Generator qvw that takes about 3 hours to refresh and upon its successful completion it triggers the refresh of 4 others qvws which pull data from the qvds generated by the Parent QVD Generator.

Hence my question is

Lets say my Parent QVD generator is set for an hourly refresh

I start my refresh at 10:00 am and it completes around 12:55 pm. Hence the other 4 qvws refresh are triggered at 12:55 and they simultaneously finish at 1:05 pm.

However in the mean time at 1:00 pm does the Parent QVD Generator qvw starts its refresh again (this time an incremental one and hence takes far less time and creates delta qvds). If it does start then is there a chance that any of the 4 qvws or its data might get corrupted if it happens?

Thanks

Riz

1 Reply
Peter_Cammaert
Partner - Champion III
Partner - Champion III

The QVWs may fail reading data from the QVD's if the Generator starts updating them at the same time. The only consequence is that the top-level QVW reload task will fail and the previously published version of the affected QVW will stay put. QDS throws away all (temporary) documents that couldn't be reloaded succesfully.

Another result may be that - as you said yourself - QVDs end up being corrupted. This means all reload processes may start to fail because the Generator won't be able to do a decent Incremental Load. And at the same time, the four top-level QVW jobs will fail because they cannot read a corrupt QVD. They won't run anyway if their tasks are triggered by a succesful Generator reload.

Try to spread these tasks in order to avoid writing and reading the same QVD at the same time.