From owner-freebsd-stable@freebsd.org  Tue Jul 14 07:49:38 2015
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Date: Tue, 14 Jul 2015 17:19:26 +0930
From: Shane Ambler <FreeBSD@ShaneWare.Biz>
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To: Karl Denninger <karl@denninger.net>, freebsd-stable@freebsd.org
Subject: Re: FreeBSD 10.1 Memory Exhaustion
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On 14/07/2015 03:18, Karl Denninger wrote:

> The ARC is supposed to auto-size and use all available free memory.  The
> problem is that the VM system and ARC system both make assumptions that
> under certain load patterns fight with one another, and when this
> happens and ARC wins the system gets in trouble FAST.   The pattern is
> that the system will start to page RSS out rather than evict ARC, ARC
> will fill the freed space, it pages more RSS out..... you see where this
> winds up heading yes?
>

Something I noticed was that vfs.zfs.arc_free_target is smaller
than vm.v_free_target

on my desktop with 8GB I get
vfs.zfs.arc_free_target: 14091
vm.v_free_target: 43195

Doesn't that cause arc allocation to trigger swapping leaving space
for arc allocation....


-- 
FreeBSD - the place to B...Storing Data

Shane Ambler