Hi Sadhu,

> The call to “pg_stat_reset“ does reset all the statistics data for
> tables belonging to the current database but does not take care of
> shared tables e.g pg_attribute.

pg_attribute is not a shared catalog, is the mentioned scenario is also
applicable for few others tables?

I have just tried it with-out your patch:

postgres=# SELECT * FROM pg_statio_all_tables  where relid=1249;
 relid | schemaname |   relname    | heap_blks_read | heap_blks_hit |
idx_blks_read | idx_blks_hit | toast_blks_read | toast_blks_hit |
tidx_blks_read | tidx_blks_hit
-------+------------+--------------+----------------+---------------+---------------+--------------+-----------------+----------------+----------------+---------------
  1249 | pg_catalog | pg_attribute |             29 |           522 |
      8 |          673 |                 |                |
 |
(1 row)

postgres=# select pg_stat_reset();
 pg_stat_reset
---------------

(1 row)

postgres=# SELECT * FROM pg_statio_all_tables  where relid=1249;
 relid | schemaname |   relname    | heap_blks_read | heap_blks_hit |
idx_blks_read | idx_blks_hit | toast_blks_read | toast_blks_hit |
tidx_blks_read | tidx_blks_hit
-------+------------+--------------+----------------+---------------+---------------+--------------+-----------------+----------------+----------------+---------------
  1249 | pg_catalog | pg_attribute |              0 |             0 |
      0 |            0 |                 |                |
 |


We are able to reset the stats of pg_attibute without your patch.

Thanks,
Himanshu

On Fri, Aug 6, 2021 at 1:56 PM Sadhuprasad Patro <b.sa...@gmail.com> wrote:

> Hi,
>
> The call to “pg_stat_reset“ does reset all the statistics data for
> tables belonging to the current database but does not take care of
> shared tables e.g pg_attribute. Similarly to reset the statistics at
> table level, the call to “pg_stat_reset_single_table_counters“ does
> not take care of shared tables.
>
> When we reset all the statistics using the call “pg_stat_reset”, the
> postgres process internally makes calls to “
> pgstat_recv_resetcounter“, which resets the statistics of all the
> tables of the current database. But not resetting the statistics of
> shared objects using database ID as 'InvalidOid'.
>
> The same fix is made in the internal function
> “pgstat_recv_resetsinglecounter“ to reset the statistics for the
> shared table for the call "pg_stat_reset_single_table_counters".
>
> --
> thank u
> SADHU PRASAD
> EnterpriseDB: http://www.enterprisedb.com
>

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