Robert Haas wrote: > If we arranged things so that the processes could use the data in the > DSM directly rather than having to copy it out, we'd presumably save > quite a bit of memory, since the whole structure would be shared > rather than each backend having its own copy. But if the structure > got too big to map (on a 32-bit system), then you'd be sort of hosed, > because there's no way to attach just part of it. That might not be > worth worrying about, but it depends on how big it's likely to get - a > 32-bit system is very likely to choke on a 1GB mapping, and maybe even > on a much smaller one.
How realistic it is that you would get a 1 GB mapping on a 32-bit system? Each table entry is 106 bytes at the moment if my count is right, so you need about one million tables to get that large a table. It doesn't sound really realistic to have such a database on a smallish machine. -- Álvaro Herrera http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
