Get disk info from compute_node

Part of blueprint limit-container-diskspace

Change-Id: Iddbde43a417b873d6dd8c52f02c0d2165aba2c31

zun/compute/claims.py

@@ -41,6 +41,10 @@ class NopClaim(object):
     def cpu(self):
         return 0
 
+    @property
+    def disk(self):
+        return 0
+
     def __enter__(self):
         return self
 
@@ -93,6 +97,10 @@ class Claim(NopClaim):
     def cpu(self):
         return self.container.cpu or 0
 
+    @property
+    def disk(self):
+        return self.container.disk or 0
+
     def abort(self):
         """Requiring claimed resources has failed or been aborted."""
         LOG.debug("Aborting claim: %s", self)
@@ -116,13 +124,15 @@ class Claim(NopClaim):
         # unlimited:
         memory_limit = limits.get('memory')
         cpu_limit = limits.get('cpu')
+        disk_limit = limits.get('disk')
 
         LOG.info('Attempting claim: memory %(memory)s, '
-                 'cpu %(cpu).02f CPU',
-                 {'memory': self.memory, 'cpu': self.cpu})
+                 'cpu %(cpu).02f CPU, disk %(disk)s',
+                 {'memory': self.memory, 'cpu': self.cpu, 'disk': self.disk})
 
         reasons = [self._test_memory(resources, memory_limit),
                    self._test_cpu(resources, cpu_limit),
+                   self._test_disk(resources, disk_limit),
                    self._test_pci()]
         # TODO(Shunli): test numa here
         reasons = [r for r in reasons if r is not None]
@@ -156,6 +166,14 @@ class Claim(NopClaim):
 
         return self._test(type_, unit, total, used, requested, limit)
 
+    def _test_disk(self, resources, limit):
+        type_ = _("disk")
+        unit = "GB"
+        total = resources.disk_total
+        used = resources.disk_used
+        requested = self.disk
+        return self._test(type_, unit, total, used, requested, limit)
+
     def _test(self, type_, unit, total, used, requested, limit):
         """Test if the type resource needed for a claim can be allocated."""
 

zun/compute/compute_node_tracker.py

@@ -92,10 +92,10 @@ class ComputeNodeTracker(object):
                   be used to revert the resource usage if an error occurs
                   during the container build.
         """
-        # No memory, cpu, or pci_request specified, no need to claim resource
-        # now.
-        if not (container.memory or container.cpu or pci_requests):
-            self._set_container_host(context, container)
+        # No memory, cpu, disk or pci_request specified, no need to claim
+        # resource now.
+        if not (container.memory or container.cpu or pci_requests or
+                container.disk):
             return claims.NopClaim()
 
         # We should have the compute node created here, just get it.
@@ -213,6 +213,7 @@ class ComputeNodeTracker(object):
         cn.mem_free = cn.mem_total
         cn.mem_used = 0
         cn.running_containers = 0
+        cn.disk_used = 0
 
         for cnt in containers:
             self._update_usage_from_container(context, cnt)
@@ -222,10 +223,12 @@ class ComputeNodeTracker(object):
     def _update_usage(self, usage, sign=1):
         mem_usage = usage['memory']
         cpus_usage = usage.get('cpu', 0)
+        disk_usage = usage['disk']
 
         cn = self.compute_node
         cn.mem_used += sign * mem_usage
         cn.cpu_used += sign * cpus_usage
+        cn.disk_used += sign * disk_usage
 
         # free ram may be negative, depending on policy:
         cn.mem_free = cn.mem_total - cn.mem_used
@@ -294,8 +297,8 @@ class ComputeNodeTracker(object):
         if container.memory:
             memory = int(container.memory[:-1])
         usage = {'memory': memory,
-                 'cpu': container.cpu or 0}
-
+                 'cpu': container.cpu or 0,
+                 'disk': container.disk or 0}
         # update numa usage here
 
         return usage

zun/conf/compute.py

@@ -21,6 +21,10 @@ compute_opts = [
         default=True,
         help='restart the containers which are running'
              'before the host reboots.'),
+    cfg.FloatOpt(
+        'reserve_disk_for_image',
+        default=0.2,
+        help='reserve disk for docker images'),
 ]
 
 service_opts = [

zun/conf/docker.py

@@ -53,6 +53,9 @@ docker_opts = [
                default=5,
                help='Timeout in seconds for executing a command in a docker '
                     'container.'),
+    cfg.StrOpt('docker_data_root',
+               default='/var/lib/docker',
+               help='Root directory of persistent Docker state.'),
 ]
 
 ALL_OPTS = (docker_opts)

zun/container/docker/driver.py

@@ -892,6 +892,18 @@ class DockerDriver(driver.ContainerDriver):
             return (total, running, paused, stopped, cpus,
                     architecture, os_type, os, kernel_version, labels)
 
+    def get_total_disk_for_container(self):
+        try:
+            (output, err) = utils.execute('df', '-B', '1G',
+                                          CONF.docker.docker_data_root,
+                                          run_as_root=True)
+        except exception.CommandError:
+            LOG.info('There was a problem while executing df -B 1G %s',
+                     CONF.docker.docker_data_root)
+            raise exception.CommandError(cmd='df')
+        total_disk = int(output.split('\n')[1].split()[1])
+        return int(total_disk * (1 - CONF.compute.reserve_disk_for_image))
+
     def get_cpu_used(self):
         cpu_used = 0
         with docker_utils.docker_client() as docker:

zun/container/driver.py

@@ -192,6 +192,9 @@ class ContainerDriver(object):
     def get_host_info(self):
         raise NotImplementedError()
 
+    def get_total_disk_for_container(self):
+        return NotImplementedError()
+
     def get_cpu_used(self):
         raise NotImplementedError()
 
@@ -241,6 +244,8 @@ class ContainerDriver(object):
         cpu_used = self.get_cpu_used()
         node.cpu_used = cpu_used
         node.labels = labels
+        disk_total = self.get_total_disk_for_container()
+        node.disk_total = disk_total
 
     def node_is_available(self, nodename):
         """Return whether this compute service manages a particular node."""

zun/tests/unit/container/docker/test_docker_driver.py

@@ -711,13 +711,15 @@ class TestDockerDriver(base.DriverTestCase):
                                              security_groups=test_sec_group_id)
 
     @mock.patch('zun.common.utils.execute')
+    @mock.patch('zun.container.docker.driver.DockerDriver'
+                '.get_total_disk_for_container')
     @mock.patch('zun.container.driver.ContainerDriver.get_host_mem')
     @mock.patch(
         'zun.container.docker.driver.DockerDriver.get_host_info')
     @mock.patch(
         'zun.container.docker.driver.DockerDriver.get_cpu_used')
     def test_get_available_resources(self, mock_cpu_used, mock_info, mock_mem,
-                                     mock_output):
+                                     mock_disk, mock_output):
         self.driver = DockerDriver()
         mock_output.return_value = LSCPU_ON
         conf.CONF.set_override('floating_cpu_set', "0")
@@ -727,6 +729,7 @@ class TestDockerDriver(base.DriverTestCase):
                                   'CentOS', '3.10.0-123',
                                   {'dev.type': 'product'})
         mock_cpu_used.return_value = 1.0
+        mock_disk.return_value = 80
         node_obj = objects.ComputeNode()
         self.driver.get_available_resources(node_obj)
         self.assertEqual(_numa_topo_spec, node_obj.numa_topology.to_list())
@@ -744,3 +747,4 @@ class TestDockerDriver(base.DriverTestCase):
         self.assertEqual('CentOS', node_obj.os)
         self.assertEqual('3.10.0-123', node_obj.kernel_version)
         self.assertEqual({'dev.type': 'product'}, node_obj.labels)
+        self.assertEqual(80, node_obj.disk_total)