Slow initialization of something during boot

[Frank]

On 08/15/2013 01:58 PM, poma wrote:
> …
>>
>> 5th:
>> cp /usr/lib/systemd/system/lightdm.service /etc/systemd/system
>> - add 10s delay in
>> /etc/systemd/system/lightdm.service
>> i.e.
>> …
>> [Service]
>> ExecStartPre=/usr/bin/sleep 10
>> ExecStart=/usr/sbin/lightdm
>> …
>>
>> - enable it
>> i.e.
>> systemctl enable lightdm.service --force
>>
>>
>> If it works, and those 10s show as the only delay, you can try to lower
>> the value of it.
>>
>
> I've managed to produce a lag via NetworkManager disabled,
>
> systemctl status NetworkManager
> NetworkManager.service - Network Manager
>     Loaded: loaded (/usr/lib/systemd/system/NetworkManager.service; disabled)
>     Active: inactive (dead)
>
> These are the results of the application of the 'ExecStartPre' directive
> in the 'lightdm.service'
>
> ====================================================
> - default - no sleep
> ----------------------------------------------------
> systemd-analyze blame
> …
>           30.903s lightdm.service
> …
> ----------------------------------------------------
> /var/log/lightdm/lightdm.log
> …
> [+0.04s] DEBUG: Launching X Server
> …
> [+30.87s] DEBUG: Greeter connected, display is ready
> [+30.87s] DEBUG: New display ready, switching to it
> [+30.87s] DEBUG: Activating VT 1
> …
> ====================================================
> - 10s sleep
> /etc/systemd/system/lightdm.service
> …
> ExecStartPre=/usr/bin/sleep 10
> …
> ----------------------------------------------------
> systemd-analyze blame
> …
>           10.058s lightdm.service
> …
> ----------------------------------------------------
> /var/log/lightdm/lightdm.log
> …
> [+0.04s] DEBUG: Launching X Server
> …
> [+1.23s] DEBUG: Greeter connected, display is ready
> [+1.23s] DEBUG: New display ready, switching to it
> [+1.23s] DEBUG: Activating VT 1
> …
> ====================================================
> - 2s sleep
> /etc/systemd/system/lightdm.service
> …
> ExecStartPre=/usr/bin/sleep 2
> …
> ----------------------------------------------------
> systemd-analyze blame
> …
>            2.146s lightdm.service
> …
> ----------------------------------------------------
> /var/log/lightdm/lightdm.log
> …
> [+0.12s] DEBUG: Launching X Server
> …
> [+2.88s] DEBUG: Greeter connected, display is ready
> [+2.88s] DEBUG: New display ready, switching to it
> [+2.88s] DEBUG: Activating VT 1
> …
> ====================================================



    With all due respect, I don't understand what's going on here---my 
network manager is not disabled. What effect does adding sleep to
lightdm.service produce ?? I think I am missing the point :)

Regards


Frank