OS X System Lockups

The way my Macbook Pro has been behaving recently is troubling me.  I have experienced frequent system lockups - unable to force quit applications or do anything to remedy the issue.  The only way I seem to be able to fix it is to hard reboot the machine (which I hate to do!).  I have a few leads, but nothing solid yet:

1.  10.4.10 - I have seen some threads pointing to faulty airport network drivers under 10.4.10.  Since I am running 10.4.10 over an airport network most of the time, this could contribute to the issue.  None of the threads I have seen mention a complete freeze, however.  For that reason, I think that this cannot be the root cause of the issue, but just a contributing factor.

2.  Firefox 2.0.0.5 - I have found several threads that blame Firefox versions after 2.0.0.3 for system freezing, memory leaks, and other issues.  Many of these threads even suggest that the issues are cross-platform.  However, I have seen this issue a few times when no browser at all was open.  Also, I have tried using the Intel-optimized builds at http://www.beatnikpad.com/ which seemed to work better (but still exhibited the freeze), and Flock (same thing happened).  It could be the combination of the browser (network connections) + the airport bug, but still seems far-fetched.

3.  Lookupd crash - there are many threads out there that mention that lookupd can crash, leaving behind symptoms that are remarkably similar to those I have seen.  Spinning beach balls, inability to force quit, and general unresponsiveness of the system are symptoms.  In fact, I have seen messages like 'launchd: Server 47c3 in bootstrap 1103 uid 0: "/usr/sbin/lookupd"[6486]: exited abnormally: Hangup' in my system logs, which strongly suggest this may be the issue.  Unfortunately, despite installing Unlockupd (which most point to as a solution to this issue), it has recurred.

4.  cmd-tab freeze - in a recent version of OS X, there were numerous complaints of a freeze that occurred while switching applications using cmd-tab.  I have not seen mention of this occurring in 10.4.10.

I have tried the usual suspects - repairing permissions, checking for corrupted preference files, disk repair, removing system caches, rebuilding the extensions cache.  None of these seem to have fixed the issue yet.  I can't wait  for the next incremental release - this constant crashing is driving me crazy!

Blogged with Flock