Re: [Xenomai] application start is slower with xenomai 2.6.4 than 2.4.10

[Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>]

On Thu, Feb 12, 2015 at 02:23:11PM +0100, JK.Behnke@web.de wrote:
> Hello,
> 
> I noticed that running the same xenomai application against xenomai 2.6.4
> is significantly slower on start up, than it was with xenomai 2.4.10.
> Calling my xenomai application 100 times by a bash script takes about 
> 1 sec on xenomai 2.4.10. On xenomai 2.6.4 however it takes about
> 20 secs.

On what hardware? What architecture?

> Even if I strip down my application to the absolut minimum of xenomai 
> calls like this

As you may know, everything is loaded on demand, so the application
start time does not depend on the application size.

> 
> main()
> {
>   mlockall(...);
>   rt_task_shadow(...);
> }
> 
> I get the same behaviour.
> 
> I have tested this on the same hardware (x86, atom). The only difference 
> is the Linux kernel (2.6.30.8 vs 3.14.17) version and the xenomai version
> (2.4.10 vs 2.6.4).
> 
> I once mistakenly linked my xenomai 2.4.10 application against libxenomai
> and also got the same behaviour (slower startup).
> So I suspect this has something to do with libxenomai I need to link 
> against, when building xenomai applications using xenomai 2.6.4.
> 
> Is there a kind of additional setup behind the scenes in xenomai 2.6.4?

The code source is available, so you can check what happens at
startup and even time it. I am afraid people who care about start
time with Xenomai are not numerous.

-- 
					    Gilles.