This block of code takes 6 times longer to execute 2nd time

ID:138710
 
Jan 14 2012, 1:55 pm
Execute LoadWorld_Fast() twice, and it will take almost six times longer the second time...

why?

Code:
proc
    gettype(n)
        switch(n)
            if(1)
                return /turf/red
            if(2)
                return /turf/blue
            if(3)
                return /turf/green
            if(4)
                return /turf/orange
            if(5)
                return /turf/pink
            if(6)
                return /turf/yellow
mob/verb
    readtotext()
        var/savefile/f = new("world_fast.sav")
        var/ff = file("test.txt")
        f.ExportText("/", ff)
    fillrand()
        for(var/x = 1, x < 256, x ++)
            for(var/y = 1, y < 256, y++)
                var/n = rand(1,6)
                var/typet = gettype(n)
                new typet(locate(x,y,1))
    clearworld()
        for(var/turf/t in world)
            del(t)

    SaveWorld_Fast()
        var/savefile/f = new("world_fast.sav")
        var/list/l = new
        for(var/turf/t in world)
            if(!istype(t,/turf/black))
                l += "t=[t.type];x=[t.x];y=[t.y];z=[t.z]"
        f << l

    LoadWorld_Fast()
        var/timestart = world.timeofday
        if(!fexists("world_fast.sav")) return
        var/savefile/f = new("world_fast.sav")
        var/list/l = new
        f >> l
        for(var/t in l)
            var/list/params = params2list(t)
            var/path = text2path(params["t"])
            var/xx = text2num(params["x"])
            var/yy = text2num(params["y"])
            var/zz = text2num(params["z"])
            new path(locate(xx,yy,zz))
        world << world.timeofday - timestart


Problem description:
I would expect this block of code to take approximately the same amount of execution time every time... especially considering the file size is not changing in between successive loads.
Jan 17 2012, 3:27 am (Edited on Jan 17 2012, 3:59 am)
I could be wrong, but from the looks of your code, the only thing I could see to slow it down would be how the server handles file pointers, locks, etc. It's probably waiting for the first file pointer to be closed before opening the file a second time.
Don't quote me on this, as I'm not a BYOND developer, I can't tell you how this would be handled.

Try changing:

    LoadWorld_Fast()
        var/timestart = world.timeofday
        if(!fexists("world_fast.sav")) return
        var/savefile/f = new("world_fast.sav")
        var/list/l = new
        f >> l
        for(var/t in l)
            var/list/params = params2list(t)
            var/path = text2path(params["t"])
            var/xx = text2num(params["x"])
            var/yy = text2num(params["y"])
            var/zz = text2num(params["z"])
            new path(locate(xx,yy,zz))
        world << world.timeofday - timestart


To:

    LoadWorld_Fast()
        var/timestart = world.timeofday
        if(!fexists("world_fast.sav")) return
        var/savefile/f = new("world_fast.sav")
        var/list/l = new
        f >> l
        for(var/t in l)
            var/list/params = params2list(t)
            var/path = text2path(params["t"])
            var/xx = text2num(params["x"])
            var/yy = text2num(params["y"])
            var/zz = text2num(params["z"])
            new path(locate(xx,yy,zz))
        world << world.timeofday - timestart
        f = null


If I'm right in my thinking, this should cause the file pointer to be closed in order for it to be used immediately in the next function call.
Jan 29 2012, 12:00 pm
Try using this, and tell if it works. I've never tried it.
http://www.byond.com/docs/ref/info.html#/savefile/proc/ Unlock
Jan 31 2012, 3:48 am
Wait, why is is running twice? If it is loading the world, shouldn't it only have to run once?