- Prepare your target application for analysis:
- Build your target in theReleasemode.
- Create a baseline against which you can compare the performance improvements as a result of tuning.For example, you instrument your code to determine how long it takes to compress a certain file. Your original target code, augmented to provide these timing data, serves as your performance baseline. Every time you modify your target, compare the performance metrics of your optimized target with the baseline, to verify that the performance has improved.
- Prepare your target system for analysis:
- Build and install the sampling drivers, if required.
- If the drivers were not built and set up during installation (for example, lack of privileges, missing kernel development RPM, and so on),VTuneprovides an error message and enables driverless sampling data collection based on the Linux Perf* tool functionality, which has a limited scope of analysis options.Profiler
- On Ubuntu* systems,VTunemay fail to collect Hotspots and Threading analysis data if the scope of theProfilerptrace()system call application is limited.To workaround this issue for one session, set the value of thekernel.yama.ptrace_scopesysctloption to 0 with this command:sysctl -w kernel.yama.ptrace_scope=0To make this change permanent, see the corresponding Troubleshooting topic.