I'm running a python script to do some statistics and the actually memory which used is low,about 10%.And no other process cost more memory.However,when i use free -m and it shows that almost 95% memory has been used.The point is that my script should do a lot of read from files,so i wonder if there's any mechanism of Linux memory cache that caused the problem?echo 1 >> /proc/sys/vm/drop_caches works,but it seems manually.How can i reduce the memory cost and doesn't make a bad effect on reading files?