core processing delays

Originally posted by [b]theultramage[/b]
http://www.eathena.ws/board/index.php?autocom=bugtracker&showbug=2256

After testing my [url="http://www.eathena.ws/board/index.php?showtopic=198741"]performance monitoring[/url] code on an empty testserver, it became apparent that there are some very inefficient parts of the code. These should be optimized to reduce server lag.

With dynamic mobs turned off
[code][Debug]: processed timer mob_ai_lazy... in 9 ms
[Debug]: processed timer status_natural_heal_timer... in 8 ms
[/code]

The first activates once per second and is caused by lazy AI processing. That's mobs that don't have any players nearby. On a server with no players, this constitutes to around 10000 mobs. All of them have nonzero spawn time and thus are being skipped by the dynamic mobs code. Many of them are plants, which don't have any AI actions to process. Also these mobs are probably on rarely-visited maps, so there's no point to having them around. To try and eliminate this overhead, see [url="http://www.eathena.ws/board/index.php?autocom=bugtracker&showbug=1197"]#1197[/url].

The second activates twice per second and is caused by hp/sp regen processing. Here the fault lies in the fact that even though only players and homunculi (and mercenaries) are able to regen, the code processes all entries in the [i]id_db[/i] - and that also counts the 50000 npc objects inside. One possibility is to track all relevant objects in a separate regen_db and process only that. FlavioJS suggested a regen timer heap (no idea how that works) to replace the "process everything every 500ms" timer.