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Date: Wed, 30 Jan 2013 22:49:07 +0200
From: Andriy Gapon <avg@FreeBSD.org>
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Subject: Re: kva size on amd64
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on 17/10/2012 12:46 Andriy Gapon said the following:
> 
> What are the main benefits, if any, of limiting KVA space size - or in fact
> tying it to physical memory size - on amd64?
> This question is perhaps relevant to other platforms with "unlimited kva" too.

I actually already have patch that auto-sets kmem_size to kmem_size_max on amd64.

My primary motivation is that I from time to time still see reports about too
small kmem_map on non-tuned amd64 systems.   This is really ridiculous
regardless of whether there is ZFS in use or not.

Another motivation is that I really see no reason at all to artificially limit
KVA.  This creates no benefits, increases fragility and reduces flexibility.


-- 
Andriy Gapon