On 08.01.2025 22:39, Ilia Evdokimov wrote:
After the changes in v9-patch, won’t all the necessary queries now be
normalized? Since there are no longer any restrictions in the parser
hook, queries will be normalized as usual, and pgss_planner,
pgss_ExecutorStart, and ExecutorEnd will simply fetch them from
'pgss_query_texts.stat' file.
For now, this seems like the simplest approach instead of making
JumbleState available to other hooks. Moreover, if we do proceed with
that, we might be able to remove the 'pgss_query_texts.stat' file
altogether and more other improvements. In my view, if no other
options arise, we should address making JumbleState available to other
hooks in a separate thread. If you have any suggestions, I'm always
open to feedback.
I attached v9 patch with changes and test above.
Unfortunately, these changes do not achieve the intended sampling goal.
I looked into this more deeply: while the sampled-out queries do not
appear in pg_stat_statements, an entry is still allocated in the hash
table after normalization, which, in my view, should not happen when
sampling is in effect. Therefore, patch v9 is unlikely to meet our needs.
--
Best regards,
Ilia Evdokimov,
Tantor Labs LLC.
