Hi! I rebased the patches again - PGSTAT_FILE_FORMAT_ID needed to be fixed.
On 21.03.2025 22:42, Alena Rybakina wrote:
I will add it and fix the tests but later and I'll explain why.
I'm working on this issue [0] and try have already created new statistics in Statistics Collector to store database and relation vacuum statistics: PGSTAT_KIND_VACUUM_DB and PGSTAT_KIND_VACUUM_RELATION.
Vacuum statistics are saved there instead of relation's and database's statistic structure, but for some reason it is not possible to find them in the hash table when building a snapshot and display them accordingly.
I have not yet figured out where the error is.
Without solving this problem, committing vacuum statistics is not yet possible. An alternative way for us was to refuse some statistics for now for relations,
but we could not agree on which statistics should not be displayed yet and for now we are only adding them :).
I understand why this is important to display more vacuum information about vacuum statistics - it will allow us to better understand the problems of incorrect vacuum settings or, for example, notice a bug in its operation.
In order to reduce the memory consumption for storing them for those who are not going to use them, I just realized that we need to create a separate space for storing the statistics
I mentioned above (PGSTAT_KIND_VACUUM_DB and PGSTAT_KIND_VACUUM_RELATION), there is no other way to do this and I am still trying to complete this functionality.
I doubt that I will have time for this by code freeze date and even if I do, I will hardly have time for a normal review. There's really a lot more to learn related to the stat collector, so
I'm postponing it to the next commitfest.
Sorry. I'll fix the tests as soon as I finish this part, since they'll most likely either break the same way or in some new way.
Tomorrow or the day after tomorrow I will send a diff patch with what I have already managed to demonstrate the problem, since I need to bring the code to a normal form.
Maybe someone who worked with the stat collector will suddenly tell me where and what I have implemented incorrectly.
I attached also diff version that contains what I was talking about. The test case:
create table t (x int);
insert into t select id from generate_series(1,1000) id;
delete from t where id > 900;
vacuum;
select * from pg_stat_vacuum_tables where relname = 't';
--
Regards,
Alena Rybakina
Postgres Professional
