The Architectural Last Branch Records (LBRs) is published in release Intel Architecture Instruction Set Extensions and Future Features Programming Reference[0]. The main advantages of Arch LBR are [1]: - Faster context switching due to XSAVES support and faster reset of LBR MSRs via the new DEPTH MSR - Faster LBR read for a non-PEBS event due to XSAVES support, which lowers the overhead of the NMI handler. - Linux kernel can support the LBR features without knowing the model number of the current CPU.