May 7th, 2004, 16:42
Hey everyone.

This week has been quite a busy week, yet very intuitive week for me. I rolled out a couple of servers (4 to be exact) all running FreeBSD 4.9. As I continue to work with FreeBSD, I find myself asking more questions and wanting to know about the underlying things and how FreeBSD (or *BSD for that matter) works.

For instance, here is a sample output of top on my company mail gateway server:

last pid: 52143; load averages: 0.06, 0.03, 0.01
29 processes: 1 running, 28 sleeping
CPU states: 0.2% user, 0.0% nice, 0.0% system, 0.0% interrupt, 99.8% idle
Mem: 173M Active, 270M Inact, 132M Wired, 1080K Cache, 199M Buf, 1433M Free
Swap: 2048M Total, 2048M Free

What im curious about mainly is the memory portion of top. In his instance, you can see at the end, that I have 1433M Free of physical memory left. What I have noticed in my observations recently, is that FreeBSD sometimes is able to 'free' up some of this room. For example, yesterday morning, it was at 1535M Free, and during the middle of the day when I was watching it, it jumped to 1715M free.

During some maintenance last night, it dropped from 1540M to what you see now.

So im really just curious as to how FreeBSD recycles memory and will memory constantly drop as time goes on. I expect it to for the most part, but since I have seen it jump around, was curious if I can further expect to see that.

THanks guys.


May 23rd, 2004, 09:53
# ps ax | grep page
6 ?? DL 0:02.16 (pagedaemon)
Gee, I wonder what that kernel thread does.

Here's a clue for you: