High Volume Log analysis

I'm working on a multi-threaded web application that uses TCP/IP sockets to talk to/control a number of server processes. Regular debugging an app like this wrecks the timing of the multi-threaded internals, so I rely almost exclusively on post-mortem of log files produced during each test run.

Most of the log file tools are geared more to statistics. I tried one that looked like it was geared more towards developers, but it required XML and it took forever to load a file.

Is there something similar to the Logback Beagle (http://logback.qos.ch/beagle/) project for IDEA? Failing that, a good log tool that can handle large logs (2.5 million entries)?

Thank you,

Donald