# Bootup takes very long time **URL:** \ **Category:** SUSE Linux Enterprise Server\ **Created:** [November 10, 2020, 2:17pm UTC](https://forums.suse.com/t/bootup-takes-very-long-time/35369 "2020-11-10T14:17:43Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Smash](https://avatars.discourse-cdn.com/v4/letter/s/e274bd/32.png) [@Smash](https://forums.suse.com/u/Smash)\ **Post date:** [November 10, 2020, 2:17pm UTC](https://forums.suse.com/t/bootup-takes-very-long-time/35369/1 "2020-11-10T14:17:43Z")
Hello Team, I am running SLES15 SP2 on my host. And I am getting NVMe devices as a storage from a SAN box. When I have very less devices (\<50) I see the bootup time is reasonable to \< 1m. But as I increase the devices (\>1000), the bootup time increases significantly. I see that upon configuring about 6000 devices, the bootup time is about 21m, and on reaching 8000 devices, it goes uptill 33 minutes. I checked systemd-analyze blame, and I see the most time taking service is lvm2-monitor. But I couldn’t figure out why it is taking time. Moreover, dev-ttyS0 times out. Any clue on how can I speed up the bootup time. Attaching the bootup logs with 6000 devices. Regards ---
**Author:** ![malcolmlewis](https://sea2.discourse-cdn.com/flex022/user_avatar/forums.suse.com/malcolmlewis/32/11375_2.png) [@malcolmlewis](https://forums.suse.com/u/malcolmlewis)\ **Post date:** [November 10, 2020, 4:36pm UTC](https://forums.suse.com/t/bootup-takes-very-long-time/35369/2 "2020-11-10T16:36:32Z")
@Smash Hi, if possible can you upload the boot log to a paste site, eg [https://paste.opensuse.org](https://paste.opensuse.org) unverified tarballs would (or shouldn’t) be downloaded from the forum 😉 Is it just lvm2-monitor or other lvm2 services, one wonders if it’s hitting a race condition. ---
**Author:** ![Smash](https://avatars.discourse-cdn.com/v4/letter/s/e274bd/32.png) [@Smash](https://forums.suse.com/u/Smash)\ **Post date:** [November 11, 2020, 4:56am UTC](https://forums.suse.com/t/bootup-takes-very-long-time/35369/3 "2020-11-11T04:56:38Z")
Have put the boot logs at [https://paste.opensuse.org/46113668](https://paste.opensuse.org/46113668) ---
**Author:** ![malcolmlewis](https://sea2.discourse-cdn.com/flex022/user_avatar/forums.suse.com/malcolmlewis/32/11375_2.png) [@malcolmlewis](https://forums.suse.com/u/malcolmlewis)\ **Post date:** [November 11, 2020, 2:39pm UTC](https://forums.suse.com/t/bootup-takes-very-long-time/35369/4 "2020-11-11T14:39:40Z")
@Smash can you add the following to the GRUB kernel options `crashkernel=162M,high crashkernel=72M,low`? Since you have multipath disabled, have you modified `/etc/lvm/lvm.conf`? If not, can you read and modify the following lines in the above file; ```auto - multipath_component_detection = 1 + multipath_component_detection = 0 - md_component_detection = 1 + md_component_detection = 0 - udev_sync = 1 + udev_sync = 0 - udev_rules = 1 + udev_rules = 0 ``` ---
**Author:** ![Smash](https://avatars.discourse-cdn.com/v4/letter/s/e274bd/32.png) [@Smash](https://forums.suse.com/u/Smash)\ **Post date:** [November 12, 2020, 12:03pm UTC](https://forums.suse.com/t/bootup-takes-very-long-time/35369/5 "2020-11-12T12:03:26Z")
Hello Malcom, Thanks a lot for this tip. This greatly improved the boot up time. Reduced from 33 minutes to 5 minutes. But I see that udev is configuring the devices even after boot up is completed. Anyways, to increase udev threads or speed up creation of those udev files ? I have added blame and boot logs for 8000 devices. blame - [https://paste.opensuse.org/39558159](https://paste.opensuse.org/39558159) boot log - [https://paste.opensuse.org/56897874](https://paste.opensuse.org/56897874) Apart from that, I am still trying to find out how to avoid ttyS0 timing out. It starts timing out as soon as 2000 devices are added. Any clues ? ---
**Author:** ![malcolmlewis](https://sea2.discourse-cdn.com/flex022/user_avatar/forums.suse.com/malcolmlewis/32/11375_2.png) [@malcolmlewis](https://forums.suse.com/u/malcolmlewis)\ **Post date:** [November 12, 2020, 1:40pm UTC](https://forums.suse.com/t/bootup-takes-very-long-time/35369/6 "2020-11-12T13:40:16Z")
@Smash Hi, the maintenance service is transient, for postfix, are you using IPv6, If not `/etc/postfix/main.cf` needs at edit to change inet\_protocol from `all` to `ipv4`. Since your not using plymouth I would remove all the installed plymouth packages (about 10) add a zypper lock and rebuild initrd. See how that goes for the moment. ---
**Author:** ![Smash](https://avatars.discourse-cdn.com/v4/letter/s/e274bd/32.png) [@Smash](https://forums.suse.com/u/Smash)\ **Post date:** [November 18, 2020, 7:08am UTC](https://forums.suse.com/t/bootup-takes-very-long-time/35369/7 "2020-11-18T07:08:22Z")
Hello Malcom, I have done required changes, and also incorporated some changes for my needs (like addition of docker). Added new logs for 8000 devices. Though systemd-analyze reported as - Startup finished in 4.029s (kernel) + 2min 30.783s (initrd) + 3min 13.203s (userspace) = 5min 48.016s Blame[8000]: [https://paste.opensuse.org/64440302](https://paste.opensuse.org/64440302) Boot log[8000]: [https://paste.opensuse.org/86475707](https://paste.opensuse.org/86475707) But when I had 16K devices configured the time to boot up shot to 12 min - Startup finished in 4.029s (kernel) + 9min 9.478s (initrd) + 3min 21.455s (userspace) = 12min 34.962s Blame [16000]: [https://paste.opensuse.org/570656](https://paste.opensuse.org/570656) Boot log [16000]: [https://paste.opensuse.org/99398385](https://paste.opensuse.org/99398385) Any idea, why “dracut-initqueue.service” is taking so long with 16K devices ? At the end things are in much better shape now, except that I am not able to login to console due to ttyS0 timing out, for which I don’t have any solution yet. Thanks