From owner-freebsd-fs@FreeBSD.ORG  Wed Jul  3 19:05:40 2013
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Date: Wed, 3 Jul 2013 21:05:40 +0200
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Subject: O_DIRECT|O_SYNC semantics?
From: Zoltan Arnold NAGY <zoltan.arnold.nagy@gmail.com>
To: freebsd-fs@freebsd.org
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Hi,

Could someone have a look here:
http://serverfault.com/questions/520141/please-explain-my-fio-results-is-o-synco-direct-misbehaving-on-linux

Basically, I'm seeing wastly different results on Linux and on FreeBSD 9.1.
Either FreeBSD's not honoring O_SYNC properly, or Linux does something
wicked.

I've been at it for a few days, without any real progress.

I do realize that since I'm operating at a block device level not with any
filesystem it's strange to ask on -fs, but I came to this results while
experimenting with the SSD as a ZIL device, and was surprised at the low
numbers.

Thanks,
Zoltan