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#### Description This is a small performance improvement, the goal is to avoid issuing rollbacks if not necessary. On my setup, Kamailio presence executes a lot of ROLLBACKS in MariaDB since function process_dialogs() runs repeatedly. What see inside MariaDB logs is the following

``` SET autocommit=0 select `presentity_uri`,`callid`,`to_tag`,`from_tag`,`event` from `active_watchers` where `updated`=3 AND `event`<>'presence.winfo'\G ROLLBACK ```

Maybe we can improve this behaviour telling presence to do autocommit to do not execute them if the select returns zero elements?

You can view, comment on, or merge this pull request online at:

https://github.com/kamailio/kamailio/pull/3183

-- Commit Summary --

* presence: No autocommit+rollback if no active watchers

-- File Changes --

M src/modules/presence/notify.c (20)

-- Patch Links --

https://github.com/kamailio/kamailio/pull/3183.patch https://github.com/kamailio/kamailio/pull/3183.diff