From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sasha Levin <levinsasha928@gmail.com>
Subject: RE: [RFC v2 PATCH] kvm tools, qcow: Add the support for
 copy-on-write clusters
Date: Sun, 20 Nov 2011 08:23:02 +0200
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On Sun, 2011-11-20 at 14:14 +0800, Lan, Tianyu wrote:
> OK. Thx.
> But fsync is too slow. I try to find a way to sync a range of file. 
> Are there any solutions to meet my purpose?

fdatasync() is as good as it'll get.

tbh, maybe we should just consider opening QCOW images with O_SYNC and
just get it over with?

> Thanks
> Tianyu Lan
> 
> -----Original Message-----
> From: Sasha Levin [mailto:levinsasha928@gmail.com] 
> Sent: Sunday, November 20, 2011 12:27 AM
> To: Lan, Tianyu
> Cc: Kevin Wolf; penberg@kernel.org; kvm@vger.kernel.org; asias.hejun@gmail.com; prasadjoshi124@gmail.com
> Subject: RE: [RFC v2 PATCH] kvm tools, qcow: Add the support for copy-on-write clusters
> 
> On Sat, 2011-11-19 at 23:30 +0800, Lan, Tianyu wrote:
> > How about using the sync_file_range to sync the metadata?
> 
> sync_file_range() is only a hint, it doesn't actually assure anything.
> 

-- 

Sasha.