When will ZFS become stable?
kris at FreeBSD.org
Sun Jan 6 13:42:45 PST 2008
Vadim Goncharov wrote:
> 06.01.08 @ 23:34 Kris Kennaway wrote:
>>> What is the other 512 MB of the 1 GB used for?
>> Everything else that the kernel needs address space for. Buffer
>> cache, mbuf allocation, etc.
> Aren't they allocated from the same memory zones? I have a router with
> 256 Mb RAM, it had a panic with ng_nat once due to exhausted kmem. So,
> what these number from it's sysctl do really mean?
> vm.kmem_size: 83415040
> vm.kmem_size_max: 335544320
> vm.kmem_size_scale: 3
> vm.kvm_size: 1073737728
> vm.kvm_free: 704638976
I believe that mbufs are allocated from a separate map. In your case
you only have ~80MB available in your kmem_map, which is used for
malloc() in the kernel. It is possible that ng_nat in combination with
the other kernel malloc usage exhausted this relatively small amount of
space without mbuf use being a factor.
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