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Date: Wed, 30 Jan 2013 22:58:31 +0200
From: Andriy Gapon <avg@FreeBSD.org>
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Subject: axe vm.max_wired [Was: Allow small amount of memory be mlock()'ed
 by unprivileged process?]
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on 02/06/2012 14:30 Andriy Gapon said the following:
> o  There is also vm.max_wired sysctl (with no equivalent tunable), which
> specifies number of _pages_ that can be wired system wide (by both kernel and
> userland).  But note that the limit applies only to userland requests, the
> kernel is allowed to wire new pages even when the limit is exceeded.  By default
> the limit is set to 1/3 of available pages.

I would like to propose to axe vm.max_wired limit.
It is not good when too many pages are wired, but...

This limit is quite arbitrary (why 1/3).
It's no good for ZFS systems where e.g. 90% of memory can be normally wired by
ZFS in kernel.

So this limit should be either axed or perhaps replaced with some much higher
limit like e.g. v_page_count - 2 * v_free_target or some such number "close" to
v_page_count.

-- 
Andriy Gapon