Truncated output of users

[rgruyters]

We noticed that we don't receive any metrics from certain users anymore. When investigating the radosgw_usage_exporter I saw that _get_rgw_users only ouput maximum of 1000 users.

Apparently /admin/user?format=json&list only show a maximum of 1000 users.

{'keys': [...], 'truncated': True, 'count': 1000, 'marker': '7:9666549e:users.uid::<REDACTED>$<REDACTED>'}

I have tried to increase the rgw_list_buckets_max_chunk setting in Ceph configuration, unfortunately that didn't help.

[rgruyters]

FWIW, after some testing I noticed that /metadata/user will list all users. (total of 1689)

I also noticed that the Go Ceph library still uses this method for listing. https://github.com/ceph/go-ceph/blob/master/rgw/admin/user.go#L136-L149