Passing thread pool size to IPA for parallel erasure

Adds a configuration option [deploy]disk_erasure_concurrency
to define the size of thread pool, and pass it to IPA. The value
defines the maximum number of threads can be utilized for
parallel disk erasure at IPA side.

Change-Id: Ie7fe8ac730e7ee161443b39a8c0fe79b2848fc87
Story: 1546949
Task: 26973

ironic/conf/deploy.py

@@ -66,6 +66,13 @@ opts = [
                        'node will be put in ``clean failed`` state. '
                        'If True, shred will be invoked and cleaning will '
                        'continue.')),
+    cfg.IntOpt('disk_erasure_concurrency',
+               default=1,
+               min=1,
+               help=_('Defines the target pool size used by Ironic Python '
+                      'Agent ramdisk to erase disk devices. The number of '
+                      'threads created to erase disks will not exceed this '
+                      'value or the number of disks to be erased.')),
     cfg.BoolOpt('power_off_after_deploy_failure',
                 default=True,
                 help=_('Whether to power off a node after deploy failure. '

ironic/drivers/modules/deploy_utils.py

@@ -660,6 +660,7 @@ def agent_add_clean_params(task):
     info['agent_continue_if_ata_erase_failed'] = erase_fallback
     secure_erase = CONF.deploy.enable_ata_secure_erase
     info['agent_enable_ata_secure_erase'] = secure_erase
+    info['disk_erasure_concurrency'] = CONF.deploy.disk_erasure_concurrency
 
     task.node.driver_internal_info = info
     task.node.save()

ironic/tests/unit/drivers/modules/test_deploy_utils.py

@@ -1633,6 +1633,7 @@ class AgentMethodsTestCase(db_base.DbTestCase):
         cfg.CONF.set_override('continue_if_disk_secure_erase_fails', True,
                               'deploy')
         cfg.CONF.set_override('enable_ata_secure_erase', False, 'deploy')
+        cfg.CONF.set_override('disk_erasure_concurrency', 8, 'deploy')
         with task_manager.acquire(
                 self.context, self.node.uuid, shared=False) as task:
             utils.agent_add_clean_params(task)
@@ -1644,6 +1645,8 @@ class AgentMethodsTestCase(db_base.DbTestCase):
                 'agent_continue_if_ata_erase_failed'])
             self.assertIs(False, task.node.driver_internal_info[
                 'agent_enable_ata_secure_erase'])
+            self.assertEqual(8, task.node.driver_internal_info[
+                'disk_erasure_concurrency'])
 
     @mock.patch.object(pxe.PXEBoot, 'prepare_ramdisk', autospec=True)
     @mock.patch('ironic.conductor.utils.node_power_action', autospec=True)

releasenotes/notes/parallel-erasure-1943da9b53a2095d.yaml

@@ -0,0 +1,9 @@
+---
+features:
+  - Adds a configuration option ``[deploy]disk_erasure_concurrency`` to
+    define the target pool size used by Ironic Python Agent ramdisk to
+    erase disk devices. The number of threads created by IPA to erase
+    disk devices is the minimum value of target pool size and the number of
+    disks to be erased. This feature can greatly reduce the operation time
+    for baremetals with multiple disks. For the backwards compatibility,
+    the default value is 1.