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My Leopard machine is choking on's index, bursting CPU utilization past 90% for sustained periods.

I noticed my Arq backup program keeps re-uploading a single 1.3GB file, and I have come to suspect that's the message index.

Ideally, I could "archive" items to keep the index from growing so big. Is that possible? Is that advisable? How can I reduce my massive email index without actually deleting the data?

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Ouch! And people say OUTLOOK can't deal with large files...this is nothing, comparatively. I'll never speak ill of it again... – Shinrai Feb 16 '11 at 22:56
up vote 1 down vote accepted

You could try to vacuum Mail's message index. Open Terminal and enter the following:

sqlite3 ~/Library/Mail/Envelope\ Index vacuum
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wow, i think that reacts a lot faster now. Sadly i didn't compare the size before and after the vacuum. – lajuette Feb 16 '11 at 21:37
FWIW, I tried this and mine reduced from 80M to 71M -- about 11.5% reduction – Doug Harris Feb 16 '11 at 22:48
My Envelope Index only went from 1248247808 to 1170309120 bytes (a reduction of about 6%) -- but hey, I'll take it. Thanks for the good idea. – editor Feb 17 '11 at 1:59

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