Re: pg_stat_reset_slru(name) doesn't seem to work as documented

On Fri, May 01, 2020 at 07:10:23PM +0900, Atsushi Torikoshi wrote:
>Hi,
>
>When I tried to reset a counter in pg_stat_slru using
>pg_stat_reset_slru(name),
>not only the specified counter but all the counters were reset.
>
>  postgres=# SELECT * FROM pg_stat_slru ;
>         name       | blks_zeroed | blks_hit | blks_read | blks_written |
>blks_exists | flushes | truncates |          stats_reset
>

>------------------+-------------+----------+-----------+--------------+-------------+---------+-----------+-------------------------------
>   async            |           3 |        0 |         0 |            3 |
>        0 |       0 |         0 | 2020-05-01 17:36:26.073433+09
>   clog             |           0 |       56 |         0 |            0 |
>        0 |       0 |         0 | 2020-05-01 17:36:26.073433+09
>   commit_timestamp |           0 |        0 |         0 |            0 |
>        0 |       0 |         0 | 2020-05-01 17:36:26.073433+09
>   (snip)
>
>
>  postgres=# SELECT pg_stat_reset_slru('clog');
>
>
>  postgres=# SELECT * FROM pg_stat_slru ;
>         name       | blks_zeroed | blks_hit | blks_read | blks_written |
>blks_exists | flushes | truncates |          stats_reset
>

>------------------+-------------+----------+-----------+--------------+-------------+---------+-----------+-------------------------------
>   async            |           0 |        0 |         0 |            0 |
>        0 |       0 |         0 | 2000-01-01 09:00:00+09
>   clog             |           0 |        0 |         0 |            0 |
>        0 |       0 |         0 | 2020-05-01 17:37:02.525006+09
>   commit_timestamp |           0 |        0 |         0 |            0 |
>        0 |       0 |         0 | 2000-01-01 09:00:00+09
>   (snip)
>
>
>Attached a patch.
>

Yeah, that memset is a left-over from some earlier version of the patch.
Thanks for the report and patch, I'll push this shortly.


regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
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