Cinder volume service goes down while creating/deleting multiple volumes at the same time

Environment:
Openstack Rocky
Ceph Mimic
openstack-cinder-13.0.8-0

Cinder volume status goes down while creating or deleting multiple volumes at the same time manually or while Rally test is running. All volume tasks including create and delete fail when systemctl status shows running but the cinder service-list command returns down state for cinder-volume. This issue is resolved when service is restarted.

We searched logs (used debug mode too) but did not find anything suspicious.

One thing to consider is, this issue started happening when we added 6 new OSD hosts to our Ceph cluster each containing 21 HDDs (OSD daemons), I don't know if this is important or not but thought worth mentioning. Any ideas or help is appreciated.