Ceph » rgw

When trying to make a backup of a bucket index, it fails with

1. radosgw-admin -n client.radosgw.be-west-3 bi list
   --bucket=priv-prod-up-alex > /var/backup/priv-prod-up-alex.list.backup
   2017-07-03 21:28:30.325613 7f07fb8bc9c0 0 System already converted
   ERROR: bi_list(): (4) Interrupted system call

When I grep for "idx" and I count these: # grep idx priv-prod-up-alex.list.backup | wc -l
2294942
When I do a bucket stats for that bucket I get:

1. radosgw-admin -n client.radosgw.be-west-3 bucket stats
   --bucket=priv-prod-up-alex | grep num_objects
   2017-07-03 21:33:05.776499 7faca49b89c0 0 System already converted
   "num_objects": 20148575

It looks like there are 18 million objects missing and the backup is not
complete (not sure if that's a correct assumption?). We're also afraid that
the resharding command will face the same issue.

We're running on Jewel 10.2.7
I've ran a the same command with --debug-rgw=20 --debug-ms=1 and attached the complete output in a text file.

Regards,
Maarten