Dear CentOS people,
This is just a general question related to memory management, and there may have been a thread or two about it before, but I'd like to post anyway.
A user was looking at top, whereby he found out that his two processes were 10.2g and 4836m in VIRT. They were 6.4g and 4.6g in RES respectively. 3445964k was free still. He was wondering why the system didn't use all of the physical memory available (16300960k total) before swapping out parts of the processes.
Over time, the 10.2g process had about 8g of it in SWAP. The 4836m process only had about 100m in SWAP. Much of the physical space is now used.
I guess the answer may not be that simple and I most likely haven't described everything that could have influenced the kernel's decision-making, but how does Linux decide how much of a process to be swapped out? I guess I could read the documentations on the Linux kernel, but does anyone have more general answers ready to be dispensed?
I haven't done anything with sysctl, if that comes into play at all.
Thank you,
--Koji