How to diagnose long start up My Macbook Pro (OSX 10.8.2) is taking a long time to settle down after booting. I am guessing there are some background processes/apps that are taking a while to start and hogging resources. What is the best way to diagnose this issue? Is there a tool that'll watch the processes as they startup upon booting up? I know about Activity Monitor, but because the system is so bogged down I can't open it until after things settle.
Have you tried disconnecting peripherals? I have a 30-60s delay before login items are opened, but it's removed if I unplug my Huawei USB modem.

Is there anything interesting in system.log (or the default view in Console)?

You could first try disabling login items in System Preferences > Users &amp; Groups > Login Items. After that, try disabling launchd plists by just moving them away from {~,}/Library/Launch{Agents,Daemons}/, or kernel extensions by moving them away from /System/Library/Extensions/. You can use Consultant's Canary to print a list of other components that were not preinstalled.