n6smith Posted December 15, 2011 Share Posted December 15, 2011 (edited) A client of mine recently bought a 2011 3.4Ghz 2TB HD iMac with Lion 10.7.2 preinstalled. All current updates applied. He has installed Logic 9.1.6 plus a few 3rd party plugins. Motu Ultralite with latest drives/firmware. He upgraded the memory to 16GB (4 x 4GB) If he spotlights any other drive but the internal drive he gets a Kernel Panic relating to MDS after a few minutes of indexing. If he tries to use Time Machine to backup to any drive (USB2/FW800 or a Time Capsule using both the TC's own internal HD and a USB2 attached via the rear port) he gets a TM error and a usually though not always, a Kernel Panic related again to MDS If he simply copies files to and from the internal to any external drive it works fine. I'm thinking it could be a memory issue as I cannot find any other reason... I've tried different drives/interfaces etc without any solution Anyone else got any suggestions before I try switching out his memory back to his original 8GB (4 x 2GB)? What's a good memory tester program (Free would be really good) or method? Memtest does not work correctly with 64bit Kernels! FWIW.. I am running an almost identical setup here without such issues... other than noted in a different thread about spotlight losing it's settings after installing the 9.1.6 update.. which once corrected , has worked fine again) Update: I have also re-installed Lion and all programs/plugins again from scratch... and same issue appeared right away... so I have discounted corrupted settings or software. Everything else seems to work fine without issue.. Logic runs great for example. Edited December 16, 2011 by n6smith Quote Link to comment Share on other sites More sharing options...
Eric Cardenas Posted December 15, 2011 Share Posted December 15, 2011 Seems to be something wrong with I/O. Have you tried resetting PRAM and specially SMC? Quote Link to comment Share on other sites More sharing options...
n6smith Posted December 15, 2011 Author Share Posted December 15, 2011 Good call Eric... I had reset PRAM but not SMC... I'll try that either tomorrow or later tonight if my client gets back earlier.. Quote Link to comment Share on other sites More sharing options...
n6smith Posted December 16, 2011 Author Share Posted December 16, 2011 The problem was a faulty memory stick in the 12-16GB 'slot' that was causing these issues. Replaced the stick and all is well. Quote Link to comment Share on other sites More sharing options...
Eric Cardenas Posted December 16, 2011 Share Posted December 16, 2011 The problem was a faulty memory stick in the 12-16GB 'slot' that was causing these issues. Replaced the stick and all is well. That's great. Good detective work. Quote Link to comment Share on other sites More sharing options...
n6smith Posted December 16, 2011 Author Share Posted December 16, 2011 It was a tip by one of the Apple techs that put me on the right track.. Apparently both Spotlight and Time Machine use the swap file heavily in conjunction with whatever memory the computer has installed.. to speed up their processes. As soon as either process started to utilize that last 12-16GB of RAM they would crash. Logic, on the other hand, only uses upper end memory when it is absolutely needed and so because my client was only loading in about 5-6 GBs of samples etc at a time.. Logic was stable. Simple when you think of it.. but a nightmare to diagnose when it only affected a few processes running and the others were stable. For future reference: I had to use the EFI version of Apple Service Diagnostics (ASD) to identify the faulty memory as Memtest no longer works correctly under a 64bit Kernel... and the OS version of ASD only tests the first 4GB Quote Link to comment Share on other sites More sharing options...
Eric Cardenas Posted December 17, 2011 Share Posted December 17, 2011 It was a tip by one of the Apple techs that put me on the right track.. Apparently both Spotlight and Time Machine use the swap file heavily in conjunction with whatever memory the computer has installed.. to speed up their processes. As soon as either process started to utilize that last 12-16GB of RAM they would crash. For future reference: I had to use the EFI version of Apple Service Diagnostics (ASD) to identify the faulty memory as Memtest no longer works correctly under a 64bit Kernel... and the OS version of ASD only tests the first 4GB That's very usable information. Thank you for keeping us updated. Quote Link to comment Share on other sites More sharing options...
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