Intel® VTune™ Profiler User Guide

User Guide

Contents

Microarchitecture Analysis Group

The
Microarchitecture
 analysis group introduces analysis types that help you estimate how effectively you code runs on modern hardware.
  • Microarchitecture Exploration helps identify the most significant hardware issues affecting the performance of your application. Consider this analysis type as a starting point when you do hardware-level analysis.
  • Memory Access measures a set of metrics to identify memory access related issues (for example, specific to NUMA architectures).
Prerequisites:
It is recommended to install the sampling driver for hardware event-based sampling collection types. For Linux* and Android* targets, if the sampling driver is not installed,
VTune
Profiler
 can work on Perf* (driverless collection). Be aware of the following configuration settings for Linux target systems:
  • To enable system-wide and uncore event collection that allows the measurement of DRAM and MCDRAM memory bandwidth that is a part of the Memory Access analysis type, use root or sudo to set
    /proc/sys/kernel/perf_event_paranoid
     to
    0
    . 
    echo 0>/proc/sys/kernel/perf_event_paranoid
  • To enable collection with the Microarchitecture Exploration analysis type, increase the default limit of opened file descriptors. Use root or sudo to increase the default value in
    /etc/security/limits.conf
     to
    100*
    <number_of_logical_CPU_cores>
    .
    <user>
     hard nofile
    <100 * number_of_logic_CPU_cores>
    <user>
     soft nofile
    <100 * number_of_logic_CPU_cores>

Product and Performance Information

1

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.