Arduino with gsm sim900 problem

I use arduino with gsm shield and when i write a lot of methods so program is stopped and gsm shield is shutting down after some seconds(methods is never used). When I deleted some methods, program runs as it should.

Glad you were able to fix it.

May be your Arduino SRAM Memory is full. Please see the link below

Now How to know, How much of your SRAM is being used. That I Really do not know.