Problem with cache memory


I have a problem with overfilling cache memory, using long newman runs. I run collection which adds some data to my database in live mode. It shouldnt stop but when its working about 2 hours, cache memory is filled and my computer stops working properly.

My computer has 8 GB RAM but its not enough.
Durning run, free cache memory is dropping. Old data (which is useless for me) is kept and released too slow which cause overfilling cache memory.

Moreover, I have “send no-cache header” option on but this dont do anything for me.

Have can I cope with this?
Thanks for any kind of help.