Max Kernel Memory?

David Schultz das at FreeBSD.ORG
Sat Aug 16 23:26:59 UTC 2008

On Fri, Aug 15, 2008, Barney Cordoba wrote:
> Setting vm.kmem_size to what seem to be usable values causes all kinds of memory allocations on boot. For example setting it to 1GB with 2GB installed results in a failure. 
> What is the maximum amount of memory that can be allocated to the kernel, and why can't 1/2 of the system's memory be allocated safely? We have a module with a potentially very large dynamic lookup table, with little going on in userland, so we want to allocate as much as possible to the kernel.

As I recall, you also need to tweak KVA_PAGES on i386. The kernel
map can't be bigger than the total amount of address space alotted
to the kernel.

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