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What benefits are there to running a 64-bit Operating System?
I bought a small 256MB slice from slicehost and installed Ubuntu 10.04 64bit and wordpress on it. Performance was dismal as apache was eating up all my memory. Once I did some taming of apache and switched to fCGI things ran fine.
Next I rebuilt as a 32 bit server, and performance was much better.
What benefit would I get from a 64 bit server. Is it all about the memory?