Re: restoring a shadow

Turbo Fredriksson wrote:
>
> In my attempts of trying to increase performance and redundancy, I
> have trying to get rServ replication to work.
>
> I have successfully been able to replicate between two databases on
> localhost.
>
> test -> Main db
> test_slave -> Slave db
>
> The 'test' database is located in PGDATA (/var/lib/pgsql/data), and
> 'test_slave' in PGDATA2 (/var/lib/pgsql/data2). Works fine (although
> I'm a little unhappy about the replication speed).
>
> Now, I'd like to have PGDATA in a ram disk (we're only expecting a
> maximum of 10-15Mb of data). The problem is if the machine is being
> reset (hardware vice) or if it crashes. Then the ram disk is
> lost. This is where PGDATA2 comes into play...

Why bother with a RAM disk? If you only have a few megabytes, why not just
allocate a large number of buffers to PostgreSQL. Most, if not everything
should end up in RAM. Up your shared memory limites and give tones to
PostgreSQL. We do that where I work, and I have seen 100% cache hit rate on
some queries.