Performance Counters

From blackwiki

• Normally driven through MSRs
• RDPMC instruction: http://www.x86.org/secrets/opcodes/rdpmc.htm
• FreeBSD includes libpmc as part of the base system
• On Linux, we have libpfm from perfmon2
• This is the preferred way we get at TSC (TSC has fallen out of favor, though)
• Collectors include oprofile and perf.