[GENERAL] Tracking database activity

[Erik Jones]

Hi, I'm hoping someone can help me wrap my head around some #s I'm using 
to track database activity.  I have a script that runs hourly and 
queries pg_stat_database and checks age(datfrozenxid) in pg_database.  
It logs those stats and the next hour, when it runs, it takes the 
differences to check the amount of activity over the last hour and then 
logs the new stats.  I was previously under the impression that by 
tracking age(datfrozenxid) in pg_database over time I'd be able to know 
how many transactions were processed in a certain amount of time.  
However, I've seend that pg_stat_database.xact_commit + 
pg_stat_database.xact_rollback < pg_database.age(datfrozenxid) by a 
factor of as much as 6 for any given time frame.  Am I misunderstanding 
something here?  Where is the discrepancy coming from?

--
erik jones <[EMAIL PROTECTED]>
software development
emma(r)

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