FreeBSD 11.x thread creation time is 9000+ microseconds on Intel Xeon Gold series CPU

[Steevan Rodrigues]

Thanks to all of you for the quick responses.

I see this issue only  on a particular server.
I do not see this issue on another server with slightly older processor
Intel(R) Xeon(R) CPU E5-2620 v2 @ 2.10GHz  (dual socket 6 core per socket)
In this system the same program takes only about 800 usec

I wonder whether it is problem with 11.x FreeBSD release on this particular
processor.
I came across two results (given below)  from Phoronix OSbench test suite
which also show poor thread creation time for FreeBSD 11.x

https://openbenchmarking.org/result/1804094-AR-1804096AR58
https://openbenchmarking.org/result/1807114-RA-WINDOWSSE47

In this look for "Create Threads"  row.

Thanks
Steevan

On Tue, Nov 6, 2018 at 3:17 PM Guido Falsi <mad at madpilot.net> wrote:

> On 06/11/18 10:01, Steevan Rodrigues wrote:
> > Ok. Sorry about that.  Again I have attached that test program as a tar
> > file. I am not sure whether even this gets stripped by mailing list
> > software.
> >
> > Anyway here is the program given below.
> >
>
> I'm not a kernel guy or an expert in such things, but I see that
> flamegraphs are often used to analyze such issues. It gives an idea
> where the kernel is actually spending it's time.
>
> There's also a port to help with this:
>
> https://www.freshports.org/benchmarks/flamegraph/
>
> I think if you could gather such information and make it available you'd
> make it easier for experts to explain what is happening and maybe also
> do something about this.
>
> --
> Guido Falsi <mad at madpilot.net>
>