cgroup: add note w.r.t. adding new params to change_cpu_shares

Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>

diff --git a/src/PVE/CGroup.pm b/src/PVE/CGroup.pm
index 2114c25090b6b9231a479e4f26aebe40f63e9867..7a83ff8a25cc4fae4b7e4a33dbb904cc3392aff4 100644 (file)
--- a/src/PVE/CGroup.pm
+++ b/src/PVE/CGroup.pm
@@ -517,6 +517,10 @@ sub clamp_cpu_shares {
 # It is left to the user to figure this out for now.
 #
 # Dies on error (including a not-running or currently-shutting-down guest).
 # It is left to the user to figure this out for now.
 #
 # Dies on error (including a not-running or currently-shutting-down guest).

+#
+# NOTE: if you add a new param during 7.x you need to break older pve-container/qemu-server versions
+#  that previously passed a `$cgroupv1_default`, which got removed due to being ignored anyway.
+#  otherwise you risk that a old module bogusly passes some cgroup default as your new param.

 sub change_cpu_shares {
     my ($self, $shares) = @_;
 
 sub change_cpu_shares {
     my ($self, $shares) = @_;