Re: PostgreSQL as a local in-memory cache

Josh Berkus <josh@agliodbs.com> writes:
>> (a) and (d) are probably simple, if by "reprovisioning" you mean
>> "rm -rf $PGDATA; initdb".

> Exactly.  Followed by "scp database_image".  Or heck, just replacing the
> whole VM.

Right, that would work.  I don't think you really need to implement that
inside Postgres.  I would envision having the startup script do it, ie

    rm -rf $PGDATA
    cp -pr prepared-database-image $PGDATA

    # this loop exits when postmaster exits normally
    while ! postmaster ...
    do
        rm -rf $PGDATA
        cp -pr prepared-database-image $PGDATA
    done

Then all you need is a tweak to make the postmaster exit(1) after
a crash instead of trying to launch recovery.

            regards, tom lane