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diff: Processor Counter Monitor (PCM)
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  +[PCM Tools](#pcm-tools) | [Building PCM](#building-pcm-tools) | [Downloading Pre-Compiled PCM](#downloading-pre-compiled-pcm-tools) | [FAQ](#frequently-asked-questions-faq) | [API Documentation](#pcm-api-documentation) | [Environment Variables](#pcm-environment-variables) | [Compilation Options](#custom-compilation-options)
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  Processor Counter Monitor (PCM) is an application programming interface (API) and a set of tools based on the API to monitor performance and energy metrics of Intel&reg; Core&trade;, Xeon&reg;, Atom&trade; and Xeon Phi&trade; processors. PCM works on Linux, Windows, Mac OS X, FreeBSD and DragonFlyBSD operating systems.
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