game loading incredibly slow on minetest 5.0

[KGM]

i have a game on minetest 5.0, running it takes ages, more than a minute.
it always says loading media.
WHY?
(it runs fast on older minetest non portable)

[Andrey01]

If you launch Minetest itself and come to something world it will load slow at first. But if you will restart the world it will load very fast! On oldest versions 0.4.10 - 0.4.15 it will load very long even if you have already come to that server.

[KGM]

but 0.4.17 loads fast also first time!

[rubenwardy]

Did you build in debug mode?
Are you connecting to a server? If so, are you certain it's the exact same commit?

[KGM]

minetest 0.5 portable installed using the script at viewtopic.php?f=42&t=3837&hilit=compile+minetest