[systemd-devel] device enumeration by systemd user instances

[Pawel Szewczyk]

On 7/17/19 23:14, Greg KH wrote:
> 
> 100ms seems like a really long time, what exactly is it doing during
> that time?  Is the kernel spending too much time regenerating the
> uevents?
> 
> How many devices are you talking about?  Any chance to see what really
> is happening here by running perf to see where the hot-spots are?

There are ~80 devices being enumerated and 1ms per device still seem a 
little too long. Note, that we are running this on arm architecture.

Maybe using perf or other tools to find out what exactly is taking this 
time is a good idea (never used perf to be honest). For now just by 
adding some verbose logs it seems that processing of each device 
actually takes around 1ms.

Regards,
Paweł Szewczyk