Re: 9.4 regression

On Thu, Aug  8, 2013 at 04:33:05PM -0500, Jon Nelson wrote:
> > How much slower would it be if we wrote it with zeros after
> > posix_fallocate() --- that would still give use single extents.  Has
> > anyone tested to see if the write without test_fallocate() still gives
> > us one extent?
> 
> Actually, I did that test - I found that there was no longer a
> performance drop and possibly a slight performance benefit.
> I couldn't quite parse your last sentence, I assume you mean "does
> skipping the posix_fallocate altogether still produce one extent?"
> Sadly, I can't really test that properly as the ext4 filesystem I'm
> testing on is quite fresh and has lots and lots of free space.

Yes, that was the question.  I meant to say:
Has anyone tested to see if the write without posix_fallocate() stillcreates one extent per 16MB file, meaning the
posix_fallocate()isunnecessary?
 

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com
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