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

On Sat, May 02, 2020 at 02:27:33PM +0200, Tomas Vondra wrote:
>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.
>

Pushed. Thanks for the report.

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