Description of problem:
rbd map is taking more than 2 minutes to map the device on the node when there are 50 parallel requests
when have seen this behavior in ceph-csi
Version-Release number of selected component (if applicable): ceph 12.2.2
Steps to Reproduce:
1.create 50/100 rbd images
2. map 50 rbd images on the node (parallel request)
for some requests, rbd map is taking more than 2 minutes to map images on node
rbd map should be completed in few seconds even if there are N number for parallel requests
link to the upstream issue https://github.com/ceph/ceph-csi/issues/507
there is a discussion is going on in upstream, creating this bug to track the same.
This was due to an extremely resource constrained environment and extra IO induced by running mkfs.ext4. The RBD CSI driver has switched to using XFS as its default and the problem seems to be better as per the linked issue.