[Freeciv-Dev] Re: Profiling Freeciv.

[Thue <thue@xxxxxxx>]

On Thursday 04 January 2001 18:12, Gaute B Strokkenes wrote:
> Yesterday, I decided to find how profiling works and see if I could do
> anything to speed up civserver, which tends to run a bit slowly on my
> old 486 during games with large maps and lots of AIs.
>
> So, I recompiled the server with make CFLAGS="-pg -g -a -O2" and
> profiled a turn of my current game.  That is, I loaded the game, hit
> the end turn button without moving or changing anything, and quit the
> server after the end / beginning of turn processing.
>
> For those who are interested, you should be able to find the savegame
> that I used at http://www.srcf.ucam.org/~gs234/newworld14.sav.bz2
> pretty soon.  Note that this is a big (200 * 100) map with lots of
> cities.
>
> This is the (abbreviated) output from gprof:
> [snip]

-map_get_known can also be made into a macro.
-Looking a bit further I found that removing the ai_manage_explorer on 
aiunit.c:1549 cuts execution time by 25%. I am not sure that we want to 
remove it though.
-I note that find_the_shortest_path() take up a neglegtable part of the total 
time; so I will keep that in mind when I find a CPU hungry way of improving 
it :). Btw, compared to 1.10 it takes 1/5 the time per call...
-On my system I note that really_generate_warmap takes 2.36ms/call versus 
379ms/call in 1.10 :)
-city_refresh() takes a neglegtable amount of time. We skipped some calls to 
thins function because of CPU concerns, that will be revised...

Converting small functions into macros is ok, but generelly optimizations 
don't have to be very ugly before I don't think it is justified for 
performance IMO. Most people have a better processor than a 4x68.
(and those people who do have a 4x86 shouldn't play 15 AI games on 160x90 
maps). On your system an AI turn took15 minutes, on my celeron 400 it took 1 
minute. And people will continue to get faster systems.

-Thue