James Bensley wrote:
Hey Listee's
I have a CentOS server with 2GB of ram and a swap drive of 4GB;
swapon -a shows my swap drive as 4GB with only about 350 bytes in use (which is fine as my server idles with about 350-400MB ram usage so no swap should be in use. However my one and only swap drive had a priority of -1. I had read that the swap drive priority doesn't matter too much because I only have one swap drive so the kernel hasn't got to make a choice but also that after a certain kernel version (which is think was like 1.3.x?) it didn't even use the priority value and my kernel is newer (I have 2.6.18-128.1.6.e15).
Basically I have read difference things from difference source on the old interwebwrok and seek clarification. In the confusion I set my swap drive priority from -1 to 1 because I thought that if the drive priority were a negative value it might not actually use the swap drive. Ultimately I can't tell because there currently isn't enough memory usage demand on the server.
On a side note: I'm a reformed Windows admin and have seen the light and am moving each server one at a time over to Linux so I am used to poor memory management and needing massive page files. Realistically the swap drive shouldn't been in use but I am just worried then when this server goes live it will hit 2GB of ram usage and the swap won't kick in. Is there anyway I can check?
If your system starts to swap, it really needs more memory. Otherwise you're just fine. Swap is only a last resort.
Don't worry about it.
Glenn