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To: "current@freebsd.org" <current@freebsd.org>
Subject: Re: FreeBSD-HEAD gets stuck on vnode operations
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On 13/05/13 13:18, Roger Pau Monné wrote:
> The VM can be stuck in this state for quite some time, it generally

I would like to explain this a little bit more, the syncer process
doesn't get blocked on the _mtx_trylock_flags_ call, it just continues
looping forever in what seems to be an endless loop around
mnt_vnode_next_active/ffs_sync. Also while in this state there is no
noticeable disk activity, so I'm unsure of what is happening.

> varies between a couple of minutes (5-10min) to an hour or two, after
> this the VM recovers itself and resumes normal operation. I still have
> to test this on a bare metal FreeBSD install, but I would like to ask
> if someone has seen a similar behaviour, or if someone is suspicious of
> a change that could cause this.