** Description changed: + [ Impact ] + + * Systemd calls socket(AF_NETLINK, ..., NETLINK_NETFILTER) multiple times even + when not needed. When the nfnetlink module is not available, this call is + very slow. + + * On daemon-reload this is done twice per unit. + + * The boot of UC26 is then much slower than UC24. It probably affects also + Ubuntu hybrid 26.04 (TPM/FDE). + + * We added nfnetlink kernel module to work-around it. But this module + does not belong in initrd because nothing actually uses it. Apart + from opening the socket. + + [ Test Plan ] + + * Build an initrd with https://github.com/canonical/snapd/pull/17014 + reverted. + + * Run Ubuntu Core 26 with bootchart enabled. Compare with and without + fix. The time for initrd should be shorter with the fix. This is + specially noticable around daemon-reload calls. + + [ Where problems could occur ] + + * This affects NFTSet= from systemd.resource‐control(5). + The change is simple enough that there is high confidence that + nothing will break. But if something breaks, it is for that field. + + [ Other Info ] + + * Fix was merged upstream https://github.com/systemd/systemd/pull/41930 + + [ Original report ] + It has been detected that daemon-reload requests take more time on UC26 than on UC24. The root cause is a new call to "sd_nfnl_socket_open()" in unit_modify_user_nft_set() that takes some time to run and finally fails. An optimization for this is https://pastebin.canonical.com/p/P6QFgQy5cH/ (when nft_set is empty, the call is prevented).
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2150773 Title: Slowness on UC26 on daemon-reload requests To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/2150773/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
