how to measure kernel performance

[softarts]

i.e.
I want to measure how many time spent on netif_rx(), possible to do that?

[Roman_D_Intel]

Quoting - softarts

i.e.
I want to measure how many time spent on netif_rx(), possible to do that?

Hi,

I assume netif_rx() is a Linux kernel function. Then with the SystemTap tool (http://sourceware.org/systemtap/wiki) you can insert your time measuring codeinto netif_rxon a live running system without the need to stop, rebootor recompile the kernel.

However, simpler methods might exist for your task and my method is an overkill.

Best regards,
Roman

[Thomas_W_Intel]

Alternatively to what Roman suggested, you might also have a look at oprofile, which let's you profile the Linux kernel with sampling. However, this usually requires a reboot and you may also want a kernel with debug information.

Kind regards
Thomas

[Peter_W_Intel]

Quoting - Thomas Willhalm (Intel)

Alternatively to what Roman suggested, you might also have a look at oprofile, which let's you profile the Linux kernel with sampling. However, this usually requires a reboot and you may also want a kernel with debug information.

Kind regards
Thomas

Also VTune Performance Analyzer's sampling collector can captureperformance data for all active modules in the system. In Processes report, select vmlinuz-2.6.xx-x anddrill down all modules which has samples captured - if you want to see hotfunctions in any module, the tool will ask you vmlinuz's location and its corresponding system file (usually that is like as System.map-2.6.xx-x)