This is still related to v6.5.x but I need to back up the tables before I try the upgrade.

What can I do if the backup process hangs (times out) when backing up a table? Are there any parameters I can change in the code?

The problem is that the table in question (posts) is quite large: over 500 megs.

Obviously I can erase a ton of topics to make it smaller, but what else can I do in terms of running a successful backup via the CP?