I have SOLVED the problem on my first cited machine (ASUS H81M-C motherboard) thanks to this page: https://askubuntu.com/questions/1013830/slow-boot-long-kernel-load-time-due-to-wrong-resume-device?rq=1
This is the commands I used: $ cat /etc/initramfs-tools/conf.d/resume RESUME=UUID=ab61cdaf-a2a6-40bb-a787-9d383a4490af But blkid shows that this partition does not exist anymore. I first think it was the swap partition I deleted some weeks ago, but the UUID does not correspond to the UUID I have commented in /etc/fstab. So I don't know where that UUID come from. So I typed: $ sudo vim /etc/initramfs-tools/conf.d/resume and replace its content by: RESUME=none Then I typed: $ sudo update-initramfs -u $ sudo shutdown -r now My SSD now boots very fast ! [ 2.814453] clocksource: Switched to clocksource tsc [ 2.867799] random: crng init done [ 2.994374] EXT4-fs (sda3): mounted filesystem with ordered data mode. Opts: (null) [ 3.078411] EXT4-fs (sdb1): mounted filesystem with ordered data mode. Opts: (null) I will post another message when I have access to the second machine to confirm if it solves also the problem. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1308264 Title: Ubuntu boot stuck for more than 30 seconds at "Switched to clocksource tsc" when booting up, then resumes to the login screen To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1308264/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
