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spaghettidba / WorkloadTools

A collection of tools to collect, analyze and replay SQL Server workloads, on premises and in the cloud
MIT License
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SqlWorkload does not capture all the events #67

Closed spaghettidba closed 4 years ago

spaghettidba commented 4 years ago

Some events are missing, comparing the list of events in the analysis database with the list of events in an identical extended events session

spaghettidba commented 4 years ago

Useful troubleshooting method: use a WorkloadFileWriterConsumer to write to a sqlite file and at the same time an AnalysisConsumer and compare the events captured by the two

spaghettidba commented 4 years ago

Analysis and FileWriter consumers receive the exact same number of events, so it seems like they get dropped at the listener. Configuration of the XE session?

spaghettidba commented 4 years ago

Changing the XE session to EVENT_RETENTION_MODE = NO_EVENT_LOSS fixes it. This has a potential performance impact on the server being observed, so it has to be assessed carefully.

spaghettidba commented 4 years ago

Even if the events are all captured by the XE session (at least to the file target), both analysis and FileWriter receive a subset of the events.

spaghettidba commented 4 years ago

Fixed for Extended Events files with commit 73167fd4249079735173b150be8e8f6c15ab8b98. It still need to be fixed for traces.

spaghettidba commented 4 years ago

Fixed for traces too 80e75f8527673eba5e7f5ecc594c7a210ec9d8c3