VM changes for NUMA - design doc?

[Mark Johnston]

On Mon, Nov 30, 2020 at 02:23:48AM +0000, Owens, Keith wrote:
> Is there a document that describes the current VM logic? In particular, the delayed invalidation page queues and the changes that were introduced for NUMA. I'm looking for something at the level of https://www.freebsd.org/doc/en_US.ISO8859-1/books/arch-handbook/vm.html, but more up to date. The source code comments help, but I'm hoping for an overarching design document.

No, there is no such design doc unfortunately.  The handbook is indeed
rather out of date and needs a refresh.

I'm not sure what you mean by "delayed invalidation" (this term has a
specific meaning in the amd64 pmap but has nothing to do with page
queues) but there are some block comments in vm_page.h and
vm_pagequeue.h that try to provide some explanation of the pageout code.