[systemd-devel] How to delete device units presented in systemd-analyze plot.

[Hoyer, Marko (ADITG/SW2)]

Hi Tony,

to the green box and the comment about insmod:
- Did you compile the kernel module or the whole kernel on your own? Maybe you missed stripping the kernel modules. Unstripped kernel modules can be pretty large and hence might need a long time to load depending on the storage connected. The same is true for the player binary and the shared libs ...

To the device units:
- the pink bars show that the devices are active. It has nothing to do with the time needed to activate them. These times are represented by the red bars. The pink ones are looking so long in your figures because you player needs so long to get up.

To service-udev-trigger.service:
- Udevadm trigger  is expensive, I know from my own experiences. In you figure, it is looking even worse. This service is used to trigger udevd to set up cold plug devices. If you know your cold plug devices and how to set them up (modules loading, dev node creation, setting attributes, ...) you might consider setting them up manually during startup by respective service files and do a very selective udevadm trigger (using filters for subsystems for instance) only. 

Hope this helps ...

Best regards

Marko Hoyer
Software Group II (ADITG/SW2)

Tel. +49 5121 49 6948
> -----Original Message-----
> From: systemd-devel-bounces+mhoyer=de.adit-jv.com at lists.freedesktop.org
> [mailto:systemd-devel-bounces+mhoyer=de.adit-jv.com at lists.freedesktop.org] On
> Behalf Of Tony Seo
> Sent: Sunday, August 11, 2013 6:46 PM
> To: systemd-devel at lists.freedesktop.org
> Subject: Re: [systemd-devel] How to delete device units presented in systemd-
> analyze plot.
> 
> 
> Hi.
> 
> Today, I would want to share dramatic results through your good aids.
> 
> 
> 
> Could you visit my blog to check the results?
> 
> blog: http://best-dream-boy.blogspot.kr/
> 
> (subject: 2013.08.11 - Test1,  2013.08.11 - Test2)
> 
> 
> 
> If you visit to my blog, you can see test1 and test2 picture.
> 
> Those things were results from my test board.
> 
> Since the beginning of my test, I have erased many service units thought as
> unnecessary for working my board.
> 
> 
> Yeah, I want to optimize systemd to work my board.
> 
> Finally, I got a result like "test 2" picture.
> 
> As you see two pictures,  Different things are avplayer.unit and some device
> units.
> 
> In those test,  I didn't use /etc/fstab in my systemd,
> 
> 
> The only dissimilarity was the existence of avplayer unit, and some device
> units came up.
> 
> I wonder why device unit was appeared in spite of erasing /etc/fstab.
> 
> I sincerely ask you a relationship between device unit and boot time if I
> remove unnecessary device unit.
> 
> And also, can I ask you detail process of  making device unit by systemd?
> (I alread read the manual page related with device unit)
> 
> Thanks.
> 
> 
> Tony Seo.
> 
> 
> 
> 
>