Move db files from one pgsql instance to another

Hi,

I am working right now in an strategy to improve the performance on my
server. The situation is this:

I have a very large database that it is only update once a month, but
when is updated I have to process a lot of things on the data to
create caches, aditional tables, etc.

The processing of the data can take up to 2 days in my machine so I
was considering the following strategy.

I have another machine that takes the new data, process it and when is
done I replace the files from the production server with the ones of
the processing server.

In this way I avoid my production server to become really slow for 2
days every month.

Does this sound reasonable? Am I going to find any trouble just moving
the db files inside the data/base folder? I thought I would stop
PostgreSQL, do the replacement of files, actually just changing a
symbolyc link, and start the server again. I will only have my db
stopped for 5 sec. once a month.

Has anybody experince on something like this?

Thanks in advance.

Javier.