OProfile is low-overhead in most common cases; this is dependent on the interrupt load OProfile has to deal with. The below results were obtained with a pre-release version of OProfile 0.7 on a 2.6.0-test7 kernel. The hardware was an HP Netserver LPr with two 400Mhz Pentium IIs. The overhead shown is the real-time overhead for compiling a Linux kernel several times whilst OProfile is collecting data.
The x axis shows the mean average of profiling interrupts received per second. The y axis shows the relative percentage overhead of the real time to complete the task.
For comparison, the default settings of OProfile cause around 2,000 interrupts per CPU to be generated.
A wise man proportions his belief to the evidence.- David Hume