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

[Hoyer, Marko (ADITG/SW2)]

Hi Tony,

best to my experiences, I doubt that suppressing the loading of device units will speed up systemd that much. There are other major parts that far more significantly delay the startup (cgroups in some cases, loading the unit set at startup, executing the generators, and finally loading the binary of systemd and the shared libraries ...). You'll probably gain more benefit when starting to optimize at these ends ...

Best regards

Marko Hoyer
Software Group II (ADITG/SW2)


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: Thursday, August 08, 2013 3:12 AM
> To: Mantas Mikulėnas
> Cc: systemd-devel at lists.freedesktop.org
> Subject: Re: [systemd-devel] How to delete device units presented in systemd-
> analyze plot.
> 
> 
>  I understand what you mean, but I think that I will cut the time for loading
> device unit if I keep those from appearing on my plot.
> 
>  I want to do a try to temporarily disappear some kinds of device units and
> then I'm supposed to measure boot speed depending a board of mine.(Actually, I
> believe that loading time for device unit affects to boot speed)
> 
>  What do think that loading time for device units doesn't affect to boot speed
> at machine?
> 
>  Thanks.
> 
> 
> 
> 2013/8/8 Mantas Mikulėnas <grawity at gmail.com>
> 
> 
> 	On Wed, Aug 7, 2013 at 8:03 PM, Tony Seo <tonyseo7 at gmail.com> wrote:
> 	>
> 	>  Hello.
> 	>
> 	> Now, I have studied systemd for optimizing systemd on my board.
> 	>
> 	> After edited several units, I would like to delete some device
> configuration
> 	> units existing on my picture from systemd-analyze(best-dream-
> boy.blogspot)
> 	>
> 	> I read the manual pages about systemd.device, I tried to delete
> device units
> 	> through editing /etc/fstab and systemctl mask.
> 	>
> 	> But I couldn't delete those device units, at least existing units on
> the
> 	> picture.
> 
> 
> 	You cannot delete these units because they do not exist anywhere
> 	except in memory – they're only a way to represent device status in
> 	the format of systemd units. In other words, they do not cause the
> 	problems you're having; they only make the problems visible in your
> 	bootchart.
> 
> 	--
> 	Mantas Mikulėnas <grawity at gmail.com>
> 
>