FOSS gamedev and creative worlds

hi i wanna change from 0.4.dev to 0.4.3 but it is toooo laggy
so how i can reduce lag i have disabled fancy trees ,3d clouds,smooth lightning ,opaque water and i changed the render distance to max 5 and it still lags so is another way to reduce lag???
my max fps on 0.4.dev thay was max 20
but on 0.4.3 they are max 1 fps

Lag is not "slow performance", please do not mix these terms.
If you only have 1FPS when playing with the lowest settings you should really consider getting a better computer...

it lags

You could use a smaller texture pack. Or you delete some mods (some slow down the game very hard). How many mods do you use?