I'm running a local dev server using grunt-contrib-connect and the server has become increasingly slow at loading assets and sometimes stalls out completely. I'm working collabaritively on this project via a shared repo and none of my other teammates have this problem. I've recloned the repo and started from scratch a few times, as well as uninstalling Node and reinstalling via NVM and another time from downloading the package on the Node website. The only solution I've found is booting my Mac running Mavericks in safe mode and then my connect server runs fine. Unfortunately most of my other applicatioms, such as my text editor, work poorly in safe mode. I'm curious what it could be about safe mode that is 'solving' this problem and if this is a hardware/software problem I should address with Apple. I'm currently running Node 0.10.30 via NVM.
Sounds like there might be some other processes running on your machine that could be causing a problem.
Maybe try opening Activity Monitor, sorting processes by CPU time and seeing what's at the top?