I have ubuntu server 14.04 installed in my server. And i have vsftpd server that provide download file test for testing purpose. my question is why if client download the ftp file, my server ram is increase rapidly in line with user download, and then it stays in same value, after user finish downloading, is there a way to prevent it ?
Here is capture of my ram usage.
ipeph@ServiceOperationCenter:~$ free -m
total used free shared buffers cached
Mem: 9748 6018 3720 10 141 5679
-/+ buffers/cache: 392 9354
Swap: 893 0 893
ipeph@ServiceOperationCenter:~$ date
Thu Nov 19 09:44:37 WIB 2015
ipeph@ServiceOperationCenter:~$ free -m
total used free shared buffers cached
Mem: 9748 6113 3619 10 141 5679
-/+ buffers/cache: 395 9350
Swap: 893 0 893
ipeph@ServiceOperationCenter:~$ date
Thu Nov 19 09:44:57 WIB 2015
ipeph@ServiceOperationCenter:~$ free -m
total used free shared buffers cached
Mem: 9748 6213 3534 10 141 5679
-/+ buffers/cache: 402 9355
Swap: 893 0 893
ipeph@ServiceOperationCenter:~$ date
Thu Nov 19 09:45:03 WIB 2015
free
. Look at the -/+ cache line, which shows your memory usage went from 395m to 402m, hardly an increase at all.