Re: Total memory vs. available memory

[Andrew Doran <ad%netbsd.org@localhost>]

On Mon, Feb 23, 2009 at 11:45:26AM +0000, Matthias Scheler wrote:

> 
>       Hello,
> 
> my NetBSD/amd64 system reports these two values in kernel messages
> on system startup:
> 
> total memory = 5118 MB
> avail memory = 4952 MB
> 
> Out of interest: where did the 166MB go that aren't available?
> Is that some PC voodoo where some memor gets lost because of some
> address space conflict? I can't believe that the kernel itself
> uses 166MB.

Most will be vm_page structures (not a problem unique to NetBSD). Take
5118MB and convert to units of 4kB, multiply by sizeof(vm_page).

Andrew