We have 1TB of memory on a server which hosts an SAP application.When the app is running the memory usage shown in top is around 700GB. When the app is stopped the memory usage shown in top comes down to 10GB. A reboot of the server gets the memory usage to 1GB.Even though no application is running, why does top show 10GB used and gains 9GB after reboot?Is it possible to gain that 9GB without a reboot?Output of free -g:free -g                  total used   free shared buffers cached Mem:              1009  567   442    0      0     152 -/+ buffers/cache:      415   594 Swap:              1     0     1
Linux memory usage?
linux;linux kernel;memory