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From: Anton Sayetsky <vsjcfm@gmail.com>
Date: Thu, 6 Feb 2014 19:24:17 +0200
Message-ID: <CAFG2KCJkOKh3bpWQY4e8KBqQ7zZ2-NdgQCfETpkoTReS3ObLkw@mail.gmail.com>
Subject: Re: ZFS and Wired memory, again
To: Adam Nowacki <nowakpl@platinum.linux.pl>
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2014-02-06 Adam Nowacki <nowakpl@platinum.linux.pl>:
> So what is exactly the problem here? Free memory is essentially wasted
> memory and there is still plenty of free memory available so there is no
> point to compact wired memory. Once free memory drops below
> vm.v_free_target you should see something happen.
I'll quote my first message:
>>> I'm planning to deploy a ~150 TiB ZFS pool and when playing with ZFS
>>> noticed that amount of wired memory is MUCH bigger than ARC size (in
>>> absence of other hungry memory consumers, of course).
...
>>> So why the wired ram on a machine with only minimal amount of services
>>> has grown from 92 to 719 MiB? Sometimes I can even see about a gig!
>>> I'm using 9.2-RELEASE-p1 amd64.
...
>>> When reading a pool, evict skips can increment very fast and sometimes
>>> arc metadata exceeds limit (2x-5x).