Arch Linux

Sourav

Member

From: India

Registered: 2019-04-22

Posts: 84

Website

[Solved] LXDM takes a long time to start

Hi, I have been using LXDM and XFCE4.
When I boot my system, plymouth (enabled i915 module) starts first. After that, at the time of starting LXDM and auto-login, it waits for ~20 seconds (on an SSD). My lxdm entry doesn't have any delay set up.

If I move my mouse at the time of the delay, the cursor is shown first, and XFCE launches immediately.
When I disable lxdm, and start it from TTY manually, it doesn't take more than a second to start.

What's wrong with the configuration?

Last edited by Sourav (2019-12-06 13:47:05)

loqs

Member

Registered: 2014-03-06

Posts: 18,853

Re: [Solved] LXDM takes a long time to start

Please post the journal output from a slow boot.

Sourav

Member

From: India

Registered: 2019-04-22

Posts: 84

Website

Re: [Solved] LXDM takes a long time to start

Output from

systemd-analyze blame

# systemd-analyze blame
49.510s systemd-random-seed.service       
  893ms systemd-logind.service            
  713ms lvm2-monitor.service              
  630ms dev-sda2.device                   
  434ms upower.service                    
  337ms udisks2.service                   
  243ms systemd-udevd.service             
  226ms systemd-journald.service          
  198ms systemd-timesyncd.service         
  187ms systemd-modules-load.service      
  173ms systemd-tmpfiles-setup-dev.service
  159ms systemd-journal-flush.service     
  117ms polkit.service                    
  115ms NetworkManager.service            
   85ms user@1000.service                 
   76ms zram-setup@zram0.service          
   75ms zram-setup@zram1.service          
   71ms systemd-udev-trigger.service      
   71ms dev-zram1.swap                    
   64ms plymouth-quit-wait.service        
   64ms dev-zram0.swap                    
   62ms plymouth-start.service            
   29ms accounts-daemon.service           
   25ms plymouth-read-write.service       
   24ms systemd-tmpfiles-setup.service    
   17ms wpa_supplicant.service            
   10ms dev-hugepages.mount               
   10ms user-runtime-dir@1000.service     
   10ms dev-mqueue.mount                  
   10ms kmod-static-nodes.service         
    9ms systemd-remount-fs.service        
    9ms sys-kernel-debug.mount            
    8ms systemd-sysctl.service            
    8ms systemd-update-utmp.service       
    8ms systemd-vconsole-setup.service    
    7ms systemd-rfkill.service            
    7ms systemd-user-sessions.service     
    6ms sys-kernel-config.mount           
    4ms rtkit-daemon.service              
    4ms tmp.mount                         
    2ms sys-fs-fuse-connections.mount 

When I move my mouse, after the boot, the

systemd-random-seed.service

takes a short time, ~12 seconds

Last edited by Sourav (2019-12-06 13:07:14)

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 25,094

Re: [Solved] LXDM takes a long time to start

If your CPU supports it and

lscpu | grep rdrand

gives you output, add

random.trust_cpu=on

to your kernel parameters, otherwise install and enable haveged service.

loqs

Member

Registered: 2014-03-06

Posts: 18,853

Re: [Solved] LXDM takes a long time to start

Sourav what kernel version is the system running?

Sourav

Member

From: India

Registered: 2019-04-22

Posts: 84

Website

Re: [Solved] LXDM takes a long time to start

I have seen this behaviour since the first installation on the SSD, which was about 5 months ago.

Right now my kernel details are:

bash[~] $ cat /proc/version
Linux version 5.3.11-arch1-1 (linux@archlinux) (gcc version 9.2.0 (GCC)) #1 SMP PREEMPT Tue, 12 Nov 2019 22:19:48 +0000

The good news is adding

random.trust_cpu=on

solves the issue! The system boots within 8 - 10 seconds now... Thanks for the help!

Last edited by Sourav (2019-12-06 13:19:34)

loqs

Member

Registered: 2014-03-06

Posts: 18,853

Re: [Solved] LXDM takes a long time to start

If you updated to 5.4.2 then removed random.trust_cpu=on what is the boot time?
There was a new feature in 5.4 to generate entropy https://git.kernel.org/pub/scm/linux/ke … a1b65db72b

Sourav

Member

From: India

Registered: 2019-04-22

Posts: 84

Website

Re: [Solved] LXDM takes a long time to start

After upgrading to linux 5.4.2 and removing the random.trust_cpu=true line, I get the same boot time. It's around 8 seconds...

loqs

Member

Registered: 2014-03-06

Posts: 18,853

Re: [Solved] LXDM takes a long time to start

Thank you for testing that.