kmem_map too small: 3832475648 total allocated

Bruce Cran bruce at
Mon May 10 18:10:08 UTC 2010

On Friday 30 April 2010 09:11:49 Gary Jennejohn wrote:

> A number of variables go into calculating vm.kmem_size (see kmeminit()
> in kern_malloc.c).
> In the end, the kernel won't allocate more than twice the physical memory
> size _which it has discovered_.
> The question is, how much of your physical memory does the kernel actually
> see?

It would appear that the maximum value for vm.kmem_size is twice the amount of 
"avail memory" - as opposed to the "real memory". I have 6GB installed; 6144MB 
gets detected but only 5873MB is available. Setting vm.kmem_size to 12G fails 
but 10G works.

Bruce Cran

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