Using the Purge Command in OS X Yosemite & OS X Mavericks
Many Mac users running OS X Yosemite and OS X Mavericks have noticed the purge command, which forces memory cache to be emptied as if it a computer was rebooted, throws an error when attempting to run through Terminal in OS X 10.9 or newer. In most cases that error message is “Unable to purge disk buffers: Operation not permitted”. This does not indicate that purge no longer works in Mavericks, it simply requires super user privileges to execute properly in the latest versions of Mac OS X.
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