Fix AWS quota limits for vCPUs

In the AWS adapter, when getting the quota for an instance type, set
the quota for the AWS service quota code to be the number of vCPUs
rather than the number of cores. The number of vCPUs is typically
twice the number of cores. This fixes "VcpuLimitExceeded" errors from
AWS.

Change-Id: I880e6abb84b0527363893576057aa105a5a448a5

doc/source/aws.rst

@@ -141,7 +141,7 @@ Selecting the ``aws`` driver adds the following options to the
       .. code-block:: yaml
 
          max-resources:
-           'L-43DA4232': 224
+           'L-43DA4232': 448
 
       See `instance quotas`_ for more information.
 
@@ -498,7 +498,7 @@ Selecting the ``aws`` driver adds the following options to the
          .. code-block:: yaml
 
             max-resources:
-              'L-43DA4232': 224
+              'L-43DA4232': 448
 
          See `instance quotas`_ for more information.
 

doc/source/configuration.rst

@@ -557,7 +557,7 @@ Options
           max-servers: 10
           max-cores: 200
           max-ram: 16565
-          'L-43DA4232': 224
+          'L-43DA4232': 448
 
    Each entry is a dictionary with the following keys.  Any other keys
    are interpreted as driver-specific resource limits (otherwise

nodepool/driver/aws/adapter.py

@@ -629,15 +629,18 @@ class AwsAdapter(statemachine.Adapter):
     def _getQuotaForInstanceType(self, instance_type):
         itype = self._getInstanceType(instance_type)
         cores = itype['InstanceTypes'][0]['VCpuInfo']['DefaultCores']
+        vcpus = itype['InstanceTypes'][0]['VCpuInfo']['DefaultVCpus']
         ram = itype['InstanceTypes'][0]['MemoryInfo']['SizeInMiB']
         code = self._getQuotaCodeForInstanceType(instance_type)
-        # We include cores twice: one to match the overall cores quota
-        # (which may be set as a tenant resource limit), and a second
-        # time as the specific AWS quota code which in for a specific
-        # instance type.
+        # We include cores to match the overall cores quota (which may
+        # be set as a tenant resource limit), and include vCPUs for the
+        # specific AWS quota code which in for a specific instance
+        # type. With two threads per core, the vCPU number is
+        # typically twice the number of cores. AWS service quotas are
+        # implemented in terms of vCPUs.
         args = dict(cores=cores, ram=ram, instances=1)
         if code:
-            args[code] = cores
+            args[code] = vcpus
         return QuotaInformation(**args)
 
     # This method is wrapped with an LRU cache in the constructor.

nodepool/tests/fixtures/aws/aws-limits.yaml

@@ -11,7 +11,7 @@ zookeeper-tls:
 tenant-resource-limits:
   - tenant-name: tenant-1
     max-cores: 1024
-    'L-43DA4232': 224  # high mem cores
+    'L-43DA4232': 448  # high mem vCPUs
 
 labels:
   - name: standard
@@ -34,7 +34,7 @@ providers:
           key1: value1
           key2: value2
         max-resources:
-          'L-1216C47A': 1  # standard cores
+          'L-1216C47A': 2  # standard vCPUs
         labels:
           - name: standard
             cloud-image: ubuntu1404

nodepool/tests/unit/test_driver_aws.py

@@ -240,8 +240,8 @@ class TestDriverAws(tests.DBTestCase):
             self.waitForNodeDeletion(node)
 
     @aws_quotas({
-        'L-1216C47A': 1,
-        'L-43DA4232': 224,
+        'L-1216C47A': 2,
+        'L-43DA4232': 448,
     })
     def test_aws_multi_quota(self):
         # Test multiple instance type quotas (standard and high-mem)