Re: [libvirt] [PATCH] build: use gnulib fdatasync

[Daniel P. Berrange]

On Tue, Oct 25, 2011 at 05:12:57PM +0100, Pádraig Brady wrote:
> On 10/25/2011 04:50 PM, Daniel P. Berrange wrote:
> > On Tue, Oct 25, 2011 at 09:32:13AM -0600, Eric Blake wrote:
> >> [adding bug-gnulib]
> >>
> >> On 10/25/2011 03:44 AM, Jiri Denemark wrote:
> >>> On Mon, Oct 24, 2011 at 16:44:49 -0600, Eric Blake wrote:
> >>>> Commit 1726a73 hacked around MacOS' lack of fdatasync, since
> >>>> gnulib did not have it at the time.  But now that we use newer
> >>>> gnulib, we can avoid the hack.
> >>>>
> >>>> * bootstrap.conf (gnulib_modules): Add fdatasync.
> >>>> * configure.ac (AC_CHECK_FUNCS_ONCE): Drop our own check.
> >>>> ---
> >>>>  bootstrap.conf |    1 +
> >>>>  configure.ac   |    5 +----
> >>>>  2 files changed, 2 insertions(+), 4 deletions(-)
> >>>
> >>> ACK
> >>>
> >>> BTW, are there any plans on enhancing gnulib fsync module to provide a
> >>> replacement for certain versions of OS X? Although they provide fsync, it
> >>> doesn't really sync anything and one needs to do some ioctl hackery to 
> >>> really
> >>> achieve what fsync should do.
> >>
> >> Any quick pointers to example code using that ioctl?  Then again,
> >> I'll probably find them with a quick google search myself.
> > 
> > I learnt about the problem from
> > 
> > http://www.flamingspork.com/talks/2007/06/eat_my_data.odp
> > 
> > pages 100-119 are the "fun" part of the story
> 
> I think the mysql guys got a bit confused.
> Here's an apple engineer (Dominic Giampaolo) clarifying things
> http://lists.mindrot.org/pipermail/portawiki-discuss/2005-November/000002.html

Thanks, that does clarify it. From libvirt's POV, I think a regular
fsync() is good enough then :-)


Daniel
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