could you link me a tut for this, or explain to me how to hide sections into layers?

so my radiant is getting laggy, an is making it harder to place models an objects etc. when moving things its choppy an skips alot. is there a way to increase the usable resources for radiant, like how much ram is used for it or something?> 

ohh ok, Thank you vary much!

thank you so much for response,
main #1 yes have restarted, yes i have closed all programs out of the only 3, rest are system processes. I'm vary computer savy, and am sure this error is being caused by something other then my ram. compiling only consumes about 50% or less processing power...

so I'm having this compile error after 46% of light grid compiling.
"Small hunk ran out of memory attempting to alloc 24 bytes"
I've searched it up not much out there about it. everything is pointing to my PC's system memory, witch I'm doubting cause I have 1....

so i can't make newer lights in my map. I also can't copy a working one, the copies wont work. everything was fine tell i was starting to add more lights an didn't like what i had, so i selected them an backspaced. well now i can make new ones. what could have i messed up?

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