[From
Mike Cane] Sluggish iOS 4 performance on the iPhone 3G? We have the fix
according to neowin, thanks to Mike Cane for the heads up. "After information surfaced yesterday that Apple is investigating sluggish performance on the iPhone 3G when running iOS 4, a Neowin reader posted what could be a quick and easy fix and the best part is, it actually works.
To remedy the sluggish performance (or at least one cause of it) go to “Settings->General->Home Button->Spotlight Search-> deselect every option” and this will stop background indexing on the phone. Several users reported that the fix showed immediate results and Neowin has observed improvements on two separate iPhone 3G devices."
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