BSD 8.1 and 9.1 memory increase

[Garrett Cooper]

> On Mar 31, 2015, at 17:54, Gumpula, Suresh <Suresh.Gumpula at netapp.com> wrote:
> 
> Still trying to find out the reason for more memory foot print on 9.1
> compared to 8.1 .
> Does some thing like clustering changes in page fault handling cause
> memory foot print ?
> https://svnweb.freebsd.org/base?view=revision&revision=235876
> 
> Copying Alan Cox , if could throw some inputs on this.

Superpages and how FreeBSD does its best to put runtime libraries in superpage-able comes to mind..

The VMEM for libraries is what caught us off guard last year when dealing with applications -- more libraries == greater footprint past either 8.0 or 9.0 because of changes to VM/rtld.

Conrad Meyer had a change out to reduce the footprint for libraries, but it was racy/incomplete unfortunately :/..

Hope that maybe helps...