On Thu, 15 Jun 2000, Todd Vierling wrote:

# Date: Thu, 15 Jun 2000 20:17:47 -0400 (EDT)
# From: Todd Vierling <tv@pobox.com>
# To: current-users@netbsd.org
# Subject: Re: SOFTDEPS safe for qmail? 
# 
# On Thu, 15 Jun 2000, Peter Seebach wrote:
# 
# : "safe", yes, but there's no promise that a given write will have actually
# : taken place physically in the event of a crash, only that the set of writes
# : which has happened is expected to be consistent.  qmail may be depending on
# : certain operations being really-synchronous.
# 
# Hrmpf.
# 
# I wonder, hypothetically[!], whether the softdep code could be made to honor
# fsync(2).

fsync(2) should be honored by the OS as an absolutely guaranteed to
succeed-or-fail-before-it-returns sync operation!  That way, things which
DON'T want to do that won't have to, and they enjoy all the benefits of the
softdeps, and things which need synchronous operation won't have to do
things on a different filesystem.

				--*greywolf;
--
BSD: Hackers tested, mom approved.