Helm: [question] how to delete the release without remove pod/srv/deploy/statefulset/... ?

I think you can manually remove the configmap stored in kube-system for the release object, but this isn't something you can do with helm delete.

Note: I have not tried this and is only a suggestion. Do it at your own risk on production systems. It would be best to try this on a staging instance first before you accidentally blow away your system.

I was able to test this out and it appears to work with a very basic example:

><> helm list                                                                                                                                                                         │
NAME            REVISION        UPDATED                         STATUS          CHART                   NAMESPACE                                                                     │
wordpress       1               Tue Aug 29 10:34:10 2017        DEPLOYED        wordpress-0.6.10        default                                                                       │
><> kk get cm                                                                                                                                                                         │
NAME                                 DATA      AGE                                                                                                                                    │
extension-apiserver-authentication   1         6m                                                                                                                                     │
ingress-controller-leader-nginx      0         5m                                                                                                                                     │
kube-dns                             0         5m                                                                                                                                     │
nginx-load-balancer-conf             1         5m                                                                                                                                     │
wordpress.v1                         1         11s                                                                                                                                    │
><> kk delete cm wordpress.v1                                                                                                                                                         │
configmap "wordpress.v1" deleted                                                                                                                                                      │
><> helm list                                                                                                                                                                         │
><> k get po                                                                                                                                                                          │
NAME                                   READY     STATUS              RESTARTS   AGE                                                                                                   │
wordpress-mariadb-2617265631-r9sjb     0/1       Init:0/1            0          28s                                                                                                   │
wordpress-wordpress-2765426020-rkkzp   0/1       ContainerCreating   0          28s

I'm going to close this ticket as resolved, but please re-open if this still needs to be addressed. Thanks!