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Subject: Re: [RFC PATCH v1 00/30] fs: inode->i_version rework and optimization
To: Jeff Layton <jlayton@redhat.com>,
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From: Boaz Harrosh <openosd@gmail.com>
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Date: Fri, 31 Mar 2017 00:11:11 +0300
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On 03/30/2017 09:35 PM, Jeff Layton wrote:
<>
> Yeah, I imagine we'd need a on-disk change for this unless there's
> something already present that we could use in place of a crash counter.
> 

Perhaps we can use s_mtime and/or s_wtime in some way, I'm not sure
what is a parallel for that in xfs.
	s_mtime - time-of-last mount 
	s_wtime - time-of-last mount, umount, freez, unfreez, remount, ...
Of course you'll need a per FS vector to access that.

But this will need some math foo to get the bits compacted correctly
just a thought.

Thanks
Boaz