Like many other users, I have experienced my code (on occasion) running TEN times slower than it normally does. I have read a fair number of posts about JIT and PCode but cannot determine if this is my problem since I can't reliably reproduce the slow execution! It's a bit maddening. After experiencing the slow performance, I rerun the code & it runs MUCH faster. In order to try & reproduce the slow performance, I tried "clear all" and even restarted Matlab... to no avail! The code runs fine for a while until.... at some point in the future... it becomes slow as molasses again.
Any ideas of how I can reliably reproduce the slow performance so I can attack it? I can't post my code but I should say that it is both memory and disk intensive.