I partitioned and formatted my two new drives and suddenly my CPU usage went up to half of my available processing power. I checked and there were several processes, one of which was
systemd-udevd. After stopping the service via
systemctl stop systemd-udevd everything was fine again. But the problem always reoccured after a restart right after login or when i mounted/unmounted a fs from one of my new drives.
udevadm monitor and saw a scrolling terminal, always showing the same
UDEV [359.270329] change /devices/pci0000:00/0000:00:1f.2/ata2/host1/target1:0:0/1:0:0:0/block/sdb/sdb3 (block) KERNEL[359.275809] change /devices/pci0000:00/0000:00:1f.2/ata2/host1/target1:0:0/1:0:0:0/block/sdb/sdb2 (block) KERNEL[359.282183] change /devices/virtual/block/dm-2 (block) UDEV [359.286170] change /devices/virtual/block/dm-3 (block)
I took several approaches and finally found the reason:
This ext4 feature provides multiple mount protection (MMP). MMP helps to protect the filesystem from being multiply mounted and is useful in shared storage environments.
I enabled this feature on all file systems and after disabling it, everything works fine now. I want to file a bug, but i can't fine a bug-tracker for udev. All i found is the freedesktop page of
systemd which is told to be the current project page. Anyone knows a place to file this bug?