Apple on Wednesday released Performance Update 1.0 for users of Mac OS X Leopard and a separate file for Snow Leopard users. According to notes provided with the update, Performance Update 1.0 addresses intermittent hard drive related pauses reported by a small number of customers. Notes on applying the update is available from Apple’s Web site.

Products affected are the MacBook Air (Mid 2009), MacBook Pro (17-inch, Mid 2009), MacBook Pro (13-inch, Mid 2009), MacBook Pro (15-inch, Mid 2009), MacBook Pro (15-inch, 2.53GHz, Mid 2009), iMac (20-inch, Mid 2009), MacBook Pro (17-inch, Early 2009), MacBook (13-inch, Early 2009), MacBook (13-inch, Mid 2009), MacBook (13-inch, Aluminum, Late 2008), MacBook Air (Late 2008), MacBook Pro (15-inch, Late 2008), iMac (24-inch, Early 2009), iMac (20-inch, Early 2009), Mac mini (Early 2009).

Performance Update 1.0 for Leopard and Performance Update 1.0 for Snow Leopard are available for download from Apple’s Web site or via the software update mechanism in Mac OS X.