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Date: Wed, 19 Nov 2014 14:14:24 +0800
From: Julian Elischer <julian@freebsd.org>
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Subject: Re: suspending threads before devices
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On 11/19/14, 11:43 AM, Warner Losh wrote:
> I’m almost certain you don’t want to “unmount” the filesystems. This 
> would invalidate all open file handles and would be mondo-bado, and 
> would only succeed if you forced this issue due to all the open 
> references. Perhaps you’re being imprecise. I think you want to 
> pause all the user land threads, sync the filesystems, which should 
> mark them as clean and allow for the battery to drain w/o too much 
> trouble.
I believe that is what is meant.. Terry Lambert was always pushing for 
this, though what he wanted was for the file systems to mark 
themselves clean after a certain amount of idle time, even without 
suspend.