From 146beb48ce0600b491bf084f9b049726a043f06a Mon Sep 17 00:00:00 2001 From: Pavel Hrdina Date: Mon, 22 Feb 2021 16:08:35 +0100 Subject: [PATCH] NEWS: mention cgroups on hosts with systemd bug fix Signed-off-by: Pavel Hrdina Reviewed-by: Andrea Bolognani --- NEWS.rst | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/NEWS.rst b/NEWS.rst index bee49923a5..6ca539b1cd 100644 --- a/NEWS.rst +++ b/NEWS.rst @@ -71,6 +71,23 @@ v7.1.0 (unreleased) of relying on ``VIR_DOMAIN_SNAPSHOT_CREATE_QUIESCE`` if they need finer grained control. + * cgroups: Fix how we setup and configure cgroups on hosts with systemd + + When libvirt is running on host with systemd we register every VM with + machined which creates the VM root cgroup for us as well. Before this fix + we were directly modifying files in the VM root cgroup which was incorrect + because all the files are managed by systemd. The implication was that any + change done by libvirt to cgroup attributes supported by systemd could be + removed which happens for example by running ``systemctl daemon-reload``. + + To fix the issue libvirt now uses DBus calls for some of the cgroup + attributes that distribute the resources proportionally to the cgroup + siblings and for the rest we have a new sub-cgroup that libvirt can + managed directly. + + For more details why this is necessary see + `systemd cgroup `_ documentation. + v7.0.0 (2021-01-15) ===================