Hi, I've been studying the idoiosyncracies of memory usage whilst working in Logic (7.2/Dual G5/7Gb RAM/10.4.8) to see where the resources come and go as I instantiate various instruments and their libraries... I'm a big BFD user. And RMX, Kontakt, Trilogy etc. It's fascinating to see how much each one influences memory consumption and most of the time the feedback from the Activity Viewer makes sense. But recently, I've been watching the dark blue "inactive" memory segment — which I believe to be the cached 'waiting to be re-used' memory — just fill and fill until it's, well, full. At that point I get erratic behaviour (clicks and stutters etc.) in Logic and the only thing that I can find to clear back to proper functionality is a restart. Logic doesn't crash, per se, but it certainly seems to be straining. My "active" memory segment rarely gets up much beyond a few hundred MB. Is there enough detail in this description to get some advice from someone with a bigger brain than mine, 'cos I'm not sure what's going on. Is the 'Inactive' memory segment where the machine hangs on to samples on the off-chance I might need them? If so, can I clear it — like the 'purge' commands one finds in Adobe programs? Or am I completely misunderstanding what's what? There certainly seems to be some correlation between the 'filling up' of the inactive memory segment and poor behaviour in Logic. Any advice greatly appreciated. No rush.