Re: True ACID under linux (no fsync)? - Mailing list pgsql-general

From Poul L. Christiansen
Subject Re: True ACID under linux (no fsync)?
Date
Msg-id 39FF079E.4E28FC31@cs.auc.dk
Whole thread Raw
In response to True ACID under linux (no fsync)?  (Gary Howland (During daytime) <gary-daytime@hotlava.com>)
List pgsql-general
Use the "-F" option.

I start PostgreSQL with this line:
su -l postgres -c "/usr/bin/pg_ctl  -D $PGDATA -p /usr/bin/postmaster -o
'-i -B 4096 -o -F' start >/dev/null 2>&1" < /dev/null

Poul L. Christiansen

Kevin O'Gorman wrote:
>
> I must have missed that one.  How do you turn off fsync()??
> I have lots of batch loading to do during which ACID is of no use.
>
> ++ kevin
>
> "Poul L. Christiansen" wrote:
> >
> > Strange.
> >
> > I did a test on Redhat Linux 7.0 with fsync() turned off and my
> > batchfile of inserts ran 10 times as fast. But that was on an slow PC
> > with a slow IDE harddrive.
> >
> > What Linux distribution and kernel version are you running?
> >
> > Poul L. Christiansen
> >
> > "Gary Howland (During daytime)" wrote:
> > >
> > > Hi,
> > >
> > > Just a quickie - I heard that linux does not have a working fsync() call
> > > (it has no concept of raw devices).  In other words, fsync cannot be used
> > > to ensure that data is on disk (try it with a floppy - it returns IMMEDIATELY!!! - long before the write
finishes)
> > >
> > > This is for ALL linuxes.
> > >
> > > Does this mean that postgres is unrealiable (or non ACID-conforming) under linux?
> > >
> > > Gary
> > >
> > > --
> > > Friends help you move.
> > > Real friends help you move bodies.
> > >
> > > _______________________________________________________________________
> > >
> > > Free Unlimited Internet Access! Try it now!
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> > >
> > > _______________________________________________________________________
>
> --
> Kevin O'Gorman  (805) 650-6274  mailto:kogorman@pacbell.net
> Permanent e-mail forwarder:  mailto:Kevin.O'Gorman.64@Alum.Dartmouth.org
> At school: mailto:kogorman@cs.ucsb.edu
> Web: http://www.cs.ucsb.edu/~kogorman/index.html
> Web: http://trixie.kosman.via.ayuda.com/~kevin/index.html
>
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