kamctl:Index "inserted_time"+"status" in watchers

[Ozzyboshi]

Pre-Submission Checklist

• Commit message has the format required by CONTRIBUTING guide
• Commits are split per component (core, individual modules, libs, utils, ...)
• Each component has a single commit (if not, squash them into one commit)
• No commits to README files for modules (changes must be done to docbook files
  in doc/ subfolder, the README file is autogenerated)

Type Of Change

• Small bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds new functionality)
• Breaking change (fix or feature that would change existing functionality)

Checklist:

• PR should be backported to stable branches
• Tested changes locally
• Related to issue #XXXX (replace XXXX with an open issue number)

Description

Function ps_watchers_db_timer_clean() inside src/modules/presence/subscribe.c is called repeatedly on my setup.
Each time is called it performs a delete inside table watchers comparing columns inserted_time and status which are not indexed:

MariaDB [kamailio]> explain delete from `watchers` where `inserted_time`<1656252889 AND `status`=2;
+------+-------------+----------+------+---------------+------+---------+------+------+-------------+
| id   | select_type | table    | type | possible_keys | key  | key_len | ref  | rows | Extra       |
+------+-------------+----------+------+---------------+------+---------+------+------+-------------+
|    1 | SIMPLE      | watchers | ALL  | NULL          | NULL | NULL    | NULL | 1    | Using where |
+------+-------------+----------+------+---------------+------+---------+------+------+-------------+

Can we consider adding an index improving performance a bit?

MariaDB [kamailio]> CREATE INDEX inserted_time_status_idx ON watchers (`inserted_time`, `status`);
Query OK, 0 rows affected (0.015 sec)
Records: 0  Duplicates: 0  Warnings: 0

MariaDB [kamailio]> explain delete from `watchers` where `inserted_time`<1656252889 AND `status`=2;
+------+-------------+----------+-------+--------------------------+--------------------------+---------+------+------+-------------+
| id   | select_type | table    | type  | possible_keys            | key                      | key_len | ref  | rows | Extra       |
+------+-------------+----------+-------+--------------------------+--------------------------+---------+------+------+-------------+
|    1 | SIMPLE      | watchers | range | inserted_time_status_idx | inserted_time_status_idx | 4       | NULL | 1    | Using where |
+------+-------------+----------+-------+--------------------------+--------------------------+---------+------+------+-------------+
1 row in set (0.001 sec)

[miconda]

Thanks for the PR!

But the index definition has to be done in the xml files that specify the schema src/lib/srdb1/schema/pr_watchers.xml -- repo link:

• https://github.com/kamailio/kamailio/blob/master/src/lib/srdb1/schema/pr_watchers.xml

The the sql/db creation scripts can be generated for all backends (mysql, postgres, ...) with:

make dbschema

You would need xml tools installed, you can just change the xml file and I can then regenerated the sql/db scripts.

You can force push to this PR or close and open another one.

[Ozzyboshi]

I changed the xml file and regenerated the sql files in 2 separate commits please let me know if it's ok

[henningw]

Thank you