Thread: Re: [PERFORM] Reiser4

Pierre-Fr�d�ric Caillaud wrote:
>     Is there also a possibility to tell Postgres : "I don't care if I lose 30
> seconds of transactions on this table if the power goes out, I just want
> to be sure it's still ACID et al. compliant but you can fsync less often
> and thus be faster" (with a possibility of setting that on a per-table
> basis) ?

I have been thinking about this.  Informix calls it buffered logging and
it would be a good feature.

Added to TODO:

* Allow buffered WAL writes and fsync

  Instead of guaranteeing recovery of all committed transactions, this
  would provide improved performance by delaying WAL writes and fsync
  so an abrupt operating system restart might lose a few seconds of
  committed transactions but still be consistent.  We could perhaps
  remove the 'fsync' parameter (which results in an an inconsistent
  database) in favor of this capability.

--
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
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Bruce Momjian wrote:
> Pierre-Frédéric Caillaud wrote:
> >     Is there also a possibility to tell Postgres : "I don't care if I
> > lose 30 seconds of transactions on this table if the power goes
> > out, I just want to be sure it's still ACID et al. compliant but
> > you can fsync less often and thus be faster" (with a possibility of
> > setting that on a per-table basis) ?

Then it would be "ACI" compliant.

--
Peter Eisentraut
http://developer.postgresql.org/~petere/