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() still
creates one extent per 16MB file, meaning the posix_fallocate()
is unnecessary?
--
Bruce Momjian <[email protected]> http://momjian.us
EnterpriseDB http://enterprisedb.com
+ It's impossible for everything to be true. +
--
Sent via pgsql-hackers mailing list ([email protected])
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-hackers
