Comment 8 for bug 1692775

I am still hitting the same issue even with the given fix
    def _prepare_output_data(self, data):
        if self.compressor is None:
            return 'none', data
        data_size_bytes = len(data)
        # Execute compression in native thread so it doesn't prevent
        # cooperative greenthread switching.
        compressed_data = eventlet.tpool.execute(self.compressor.compress,
                                                 data)

Started the backup for 50GB volume
[root@pvc180 cinder]# cinder --service-type volume backup-list
+--------------------------------------+--------------------------------------+----------+-------------+------+--------------+-------------------------------------------+
| ID | Volume ID | Status | Name | Size | Object Count | Container |
+--------------------------------------+--------------------------------------+----------+-------------+------+--------------+-------------------------------------------+
| 4d2a21e4-63e7-4018-a5ba-5c79bdcbfee1 | b0f5eec3-1e25-4b2e-8b91-f947b9361dfc | creating | chec-backup | 50 | 0 | 4d/2a/4d2a21e4-63e7-4018a5ba-5c79bdcbfee1 |
+--------------------------------------+--------------------------------------+----------+-------------+------+--------------+-------------------------------------------+

cinder service-list shows down for the cinder-backup
+------------------+----------------------------+------+---------+-------+----------------------------+-----------------+
| Binary | Host | Zone | Status | State | Updated_at | Disabled Reason |
+------------------+----------------------------+------+---------+-------+----------------------------+-----------------+
| cinder-backup | pvc180.rch.stglabs.ibm.com | nova | enabled | down | 2017-11-07T09:38:59.000000 | - |
| cinder-conductor | pvc180.rch.stglabs.ibm.com | nova | enabled | up | 2017-11-07T09:41:00.000000 | - |
| cinder-health | pvc180.rch.stglabs.ibm.com | nova | enabled | up | 2017-11-07T09:41:16.000000 | - |
| cinder-scheduler | pvc180.rch.stglabs.ibm.com | nova | enabled | up | 2017-11-07T09:41:00.000000 | - |
| cinder-volume | evtds8870 | nova | enabled | up | 2017-11-07T09:41:25.000000 | - |
| cinder-volume | y0121v3700b | nova | enabled | up | 2017-11-07T09:41:07.000000 | - |
+------------------+----------------------------+------+---------+-------+----------------------------+-----------------+

Once the backup is completed and available cinder-backup service is backup up.
[root@pvc180 cinder]# cinder --service-type volume backup-list
+--------------------------------------+--------------------------------------+-----------+-------------+------+--------------+--------------------------------------------+
| ID | Volume ID | Status | Name | Size | Object Count | Container |
+--------------------------------------+--------------------------------------+-----------+-------------+------+--------------+--------------------------------------------+
| 4d2a21e4-63e7-4018-a5ba-5c79bdcbfee1 | b0f5eec3-1e25-4b2e-8b91-f947b9361dfc | available | chec-backup | 50 | 201 | 4d/2a/4d2a21e4-63e7-4018-a5ba-5c79bdcbfee1 |
+--------------------------------------+--------------------------------------+-----------+-------------+------+--------------+--------------------------------------------+
[root@pvc180 cinder]# cinder service-list
+------------------+----------------------------+------+---------+-------+----------------------------+-----------------+
| Binary | Host | Zone | Status | State | Updated_at | Disabled Reason |
+------------------+----------------------------+------+---------+-------+----------------------------+-----------------+
| cinder-backup | pvc180.rch.stglabs.ibm.com | nova | enabled | up | 2017-11-07T09:52:18.000000 | - |