Pierre,
> Are there any plans in a future Postgresql version to support a special
> fsync method for Reiser4 which will use the filesystem's transaction
> engine, instead of an old kludge like fsync(), with a possibility of
> vastly enhanced performance ?
I don't know of any such in progress right now. Why don't you start it? It
would have to be an add-in since we support 28 operating systems and Reiser
is AFAIK Linux-only, but it sounds like an interesting experiment.
> 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) ?
Not per-table, no, but otherwise take a look at the Background Writer feature
of 8.0.
--
-Josh Berkus
"A developer of Very Little Brain"
Aglio Database Solutions
San Francisco