2017-04-18 21:42 GMT+02:00 Adrian Klaver <adrian.klaver@xxxxxxxxxxx>:
On 04/17/2017 09:18 AM, Tom DalPozzo wrote:
Hi, I'm using libpq to insert tuples in my table and keep looking at
statistics through psql instead.
I noticed that sometimes n_tuple_ins is not updated even after 1 min
that my transaction committed.
My libpq connection is kept alive. If I close the connection then the
stats get updated.
I know that stats are not instantaneous, but I thought that after a
while that a transaction is committed it would be updated.
Any of this apply?:
https://www.postgresql.org/docs/9.6/static/monitoring-stats. html
"Another important point is that when a server process is asked to display any of these statistics, it first fetches the most recent report emitted by the collector process and then continues to use this snapshot for all statistical views and functions until the end of its current transaction. So the statistics will show static information as long as you continue the current transaction. Similarly, information about the current queries of all sessions is collected when any such information is first requested within a transaction, and the same information will be displayed throughout the transaction. This is a feature, not a bug, because it allows you to perform several queries on the statistics and correlate the results without worrying that the numbers are changing underneath you. But if you want to see new results with each query, be sure to do the queries outside any transaction block. Alternatively, you can invoke pg_stat_clear_snapshot(), which will discard the current transaction's statistics snapshot (if any). The next use of statistical information will cause a new snapshot to be fetched."
Regards
Pupillo
I read it, it seems to say that after N millisec that my transaction ends, stat should be current. I also tried pg_stat_clear_snapshot() with no success.
Regards
Pupillo
--
Adrian Klaver
adrian.klaver@xxxxxxxxxxx
