Make worker-multiplier sane in container environments

Resync charm-helpers to pickup the capped worker-multiplier
changes when deploying in containers.

Drop the default value for worker-multiplier of 2.0; this
is now handled from within the codebase rather than via a
default configuration value, reflecting the differing
behaviours between container and non-container deployments.

Change-Id: Idb10dc73b357cc3ed774365bae92962b8dfd0bfb
Closes-Bug: 1665270

config.yaml

@@ -257,11 +257,13 @@ options:
       to run. Supported modules currently include os, ssh, apache and mysql.
   worker-multiplier:
     type: float
-    default: 2.0
+    default:
     description: |
       The CPU core multiplier to use when configuring worker processes for
-      neutron and nova-metadata-api. By default, the number of workers for
+      this service.  By default, the number of workers for each daemon is
-      each daemon is set to twice the number of CPU cores a service unit has.
+      set to twice the number of CPU cores a service unit has.  When deployed
+      in a LXD container, this default value will be capped to 4 workers
+      unless this configuration option is set.
   aa-profile-mode:
     type: string
     default: 'disable'

hooks/charmhelpers/contrib/network/ip.py

@@ -239,6 +239,16 @@ def format_ipv6_addr(address):
     return None
 
 
+def is_ipv6_disabled():
+    try:
+        result = subprocess.check_output(
+            ['sysctl', 'net.ipv6.conf.all.disable_ipv6'],
+            stderr=subprocess.STDOUT)
+        return "net.ipv6.conf.all.disable_ipv6 = 1" in result
+    except subprocess.CalledProcessError:
+        return True
+
+
 def get_iface_addr(iface='eth0', inet_type='AF_INET', inc_aliases=False,
                    fatal=True, exc_list=None):
     """Return the assigned IP address for a given interface, if any.
@@ -544,31 +554,38 @@ def assert_charm_supports_ipv6():
                         "versions less than Trusty 14.04")
 
 
-def get_relation_ip(interface, config_override=None):
+def get_relation_ip(interface, cidr_network=None):
-    """Return this unit's IP for the given relation.
+    """Return this unit's IP for the given interface.
 
     Allow for an arbitrary interface to use with network-get to select an IP.
-    Handle all address selection options including configuration parameter
+    Handle all address selection options including passed cidr network and
-    override and IPv6.
+    IPv6.
 
-    Usage: get_relation_ip('amqp', config_override='access-network')
+    Usage: get_relation_ip('amqp', cidr_network='10.0.0.0/8')
 
     @param interface: string name of the relation.
-    @param config_override: string name of the config option for network
+    @param cidr_network: string CIDR Network to select an address from.
-           override. Supports legacy network override configuration parameters.
     @raises Exception if prefer-ipv6 is configured but IPv6 unsupported.
     @returns IPv6 or IPv4 address
     """
+    # Select the interface address first
+    # For possible use as a fallback bellow with get_address_in_network
+    try:
+        # Get the interface specific IP
+        address = network_get_primary_address(interface)
+    except NotImplementedError:
+        # If network-get is not available
+        address = get_host_ip(unit_get('private-address'))
 
-    fallback = get_host_ip(unit_get('private-address'))
     if config('prefer-ipv6'):
+        # Currently IPv6 has priority, eventually we want IPv6 to just be
+        # another network space.
         assert_charm_supports_ipv6()
         return get_ipv6_addr()[0]
-    elif config_override and config(config_override):
+    elif cidr_network:
-        return get_address_in_network(config(config_override),
+        # If a specific CIDR network is passed get the address from that
-                                      fallback)
+        # network.
-    else:
+        return get_address_in_network(cidr_network, address)
-        try:
+
-            return network_get_primary_address(interface)
+    # Return the interface address
-        except NotImplementedError:
+    return address
-            return fallback

hooks/charmhelpers/contrib/openstack/amulet/utils.py

@@ -547,7 +547,7 @@ class OpenStackAmuletUtils(AmuletUtils):
         """Create the specified instance."""
         self.log.debug('Creating instance '
                        '({}|{}|{})'.format(instance_name, image_name, flavor))
-        image = nova.images.find(name=image_name)
+        image = nova.glance.find_image(image_name)
         flavor = nova.flavors.find(name=flavor)
         instance = nova.servers.create(name=instance_name, image=image,
                                        flavor=flavor)

hooks/charmhelpers/contrib/openstack/context.py

@@ -89,6 +89,7 @@ from charmhelpers.contrib.network.ip import (
     format_ipv6_addr,
     is_address_in_network,
     is_bridge_member,
+    is_ipv6_disabled,
 )
 from charmhelpers.contrib.openstack.utils import (
     config_flags_parser,
@@ -110,6 +111,7 @@ except ImportError:
 
 CA_CERT_PATH = '/usr/local/share/ca-certificates/keystone_juju_ca_cert.crt'
 ADDRESS_TYPES = ['admin', 'internal', 'public']
+HAPROXY_RUN_DIR = '/var/run/haproxy/'
 
 
 def ensure_packages(packages):
@@ -535,6 +537,8 @@ class HAProxyContext(OSContextGenerator):
     """Provides half a context for the haproxy template, which describes
     all peers to be included in the cluster.  Each charm needs to include
     its own context generator that describes the port mapping.
+
+    :side effect: mkdir is called on HAPROXY_RUN_DIR
     """
     interfaces = ['cluster']
 
@@ -542,6 +546,8 @@ class HAProxyContext(OSContextGenerator):
         self.singlenode_mode = singlenode_mode
 
     def __call__(self):
+        if not os.path.isdir(HAPROXY_RUN_DIR):
+            mkdir(path=HAPROXY_RUN_DIR)
         if not relation_ids('cluster') and not self.singlenode_mode:
             return {}
 
@@ -1226,31 +1232,50 @@ MAX_DEFAULT_WORKERS = 4
 DEFAULT_MULTIPLIER = 2
 
 
+def _calculate_workers():
+    '''
+    Determine the number of worker processes based on the CPU
+    count of the unit containing the application.
+
+    Workers will be limited to MAX_DEFAULT_WORKERS in
+    container environments where no worker-multipler configuration
+    option been set.
+
+    @returns int: number of worker processes to use
+    '''
+    multiplier = config('worker-multiplier') or DEFAULT_MULTIPLIER
+    count = int(_num_cpus() * multiplier)
+    if multiplier > 0 and count == 0:
+        count = 1
+
+    if config('worker-multiplier') is None and is_container():
+        # NOTE(jamespage): Limit unconfigured worker-multiplier
+        #                  to MAX_DEFAULT_WORKERS to avoid insane
+        #                  worker configuration in LXD containers
+        #                  on large servers
+        # Reference: https://pad.lv/1665270
+        count = min(count, MAX_DEFAULT_WORKERS)
+
+    return count
+
+
+def _num_cpus():
+    '''
+    Compatibility wrapper for calculating the number of CPU's
+    a unit has.
+
+    @returns: int: number of CPU cores detected
+    '''
+    try:
+        return psutil.cpu_count()
+    except AttributeError:
+        return psutil.NUM_CPUS
+
+
 class WorkerConfigContext(OSContextGenerator):
 
-    @property
-    def num_cpus(self):
-        # NOTE: use cpu_count if present (16.04 support)
-        if hasattr(psutil, 'cpu_count'):
-            return psutil.cpu_count()
-        else:
-            return psutil.NUM_CPUS
-
     def __call__(self):
-        multiplier = config('worker-multiplier') or DEFAULT_MULTIPLIER
+        ctxt = {"workers": _calculate_workers()}
-        count = int(self.num_cpus * multiplier)
-        if multiplier > 0 and count == 0:
-            count = 1
-
-        if config('worker-multiplier') is None and is_container():
-            # NOTE(jamespage): Limit unconfigured worker-multiplier
-            #                  to MAX_DEFAULT_WORKERS to avoid insane
-            #                  worker configuration in LXD containers
-            #                  on large servers
-            # Reference: https://pad.lv/1665270
-            count = min(count, MAX_DEFAULT_WORKERS)
-
-        ctxt = {"workers": count}
         return ctxt
 
 
@@ -1258,7 +1283,7 @@ class WSGIWorkerConfigContext(WorkerConfigContext):
 
     def __init__(self, name=None, script=None, admin_script=None,
                  public_script=None, process_weight=1.00,
-                 admin_process_weight=0.75, public_process_weight=0.25):
+                 admin_process_weight=0.25, public_process_weight=0.75):
         self.service_name = name
         self.user = name
         self.group = name
@@ -1270,8 +1295,7 @@ class WSGIWorkerConfigContext(WorkerConfigContext):
         self.public_process_weight = public_process_weight
 
     def __call__(self):
-        multiplier = config('worker-multiplier') or 1
+        total_processes = _calculate_workers()
-        total_processes = self.num_cpus * multiplier
         ctxt = {
             "service_name": self.service_name,
             "user": self.user,
@@ -1602,7 +1626,7 @@ class MemcacheContext(OSContextGenerator):
     """Memcache context
 
     This context provides options for configuring a local memcache client and
-    server
+    server for both IPv4 and IPv6
     """
 
     def __init__(self, package=None):
@@ -1620,13 +1644,24 @@ class MemcacheContext(OSContextGenerator):
             # Trusty version of memcached does not support ::1 as a listen
             # address so use host file entry instead
             release = lsb_release()['DISTRIB_CODENAME'].lower()
-            if CompareHostReleases(release) > 'trusty':
+            if is_ipv6_disabled():
-                ctxt['memcache_server'] = '::1'
+                if CompareHostReleases(release) > 'trusty':
+                    ctxt['memcache_server'] = '127.0.0.1'
+                else:
+                    ctxt['memcache_server'] = 'localhost'
+                ctxt['memcache_server_formatted'] = '127.0.0.1'
+                ctxt['memcache_port'] = '11211'
+                ctxt['memcache_url'] = '{}:{}'.format(
+                    ctxt['memcache_server_formatted'],
+                    ctxt['memcache_port'])
             else:
-                ctxt['memcache_server'] = 'ip6-localhost'
+                if CompareHostReleases(release) > 'trusty':
-            ctxt['memcache_server_formatted'] = '[::1]'
+                    ctxt['memcache_server'] = '::1'
-            ctxt['memcache_port'] = '11211'
+                else:
-            ctxt['memcache_url'] = 'inet6:{}:{}'.format(
+                    ctxt['memcache_server'] = 'ip6-localhost'
-                ctxt['memcache_server_formatted'],
+                ctxt['memcache_server_formatted'] = '[::1]'
-                ctxt['memcache_port'])
+                ctxt['memcache_port'] = '11211'
+                ctxt['memcache_url'] = 'inet6:{}:{}'.format(
+                    ctxt['memcache_server_formatted'],
+                    ctxt['memcache_port'])
         return ctxt

hooks/charmhelpers/core/host.py

@@ -191,7 +191,7 @@ def service_pause(service_name, init_dir="/etc/init", initd_dir="/etc/init.d",
     upstart_file = os.path.join(init_dir, "{}.conf".format(service_name))
     sysv_file = os.path.join(initd_dir, service_name)
     if init_is_systemd():
-        service('disable', service_name)
+        service('mask', service_name)
     elif os.path.exists(upstart_file):
         override_path = os.path.join(
             init_dir, '{}.override'.format(service_name))
@@ -224,7 +224,7 @@ def service_resume(service_name, init_dir="/etc/init",
     upstart_file = os.path.join(init_dir, "{}.conf".format(service_name))
     sysv_file = os.path.join(initd_dir, service_name)
     if init_is_systemd():
-        service('enable', service_name)
+        service('unmask', service_name)
     elif os.path.exists(upstart_file):
         override_path = os.path.join(
             init_dir, '{}.override'.format(service_name))

tests/charmhelpers/contrib/network/ip.py

@@ -239,6 +239,16 @@ def format_ipv6_addr(address):
     return None
 
 
+def is_ipv6_disabled():
+    try:
+        result = subprocess.check_output(
+            ['sysctl', 'net.ipv6.conf.all.disable_ipv6'],
+            stderr=subprocess.STDOUT)
+        return "net.ipv6.conf.all.disable_ipv6 = 1" in result
+    except subprocess.CalledProcessError:
+        return True
+
+
 def get_iface_addr(iface='eth0', inet_type='AF_INET', inc_aliases=False,
                    fatal=True, exc_list=None):
     """Return the assigned IP address for a given interface, if any.
@@ -544,31 +554,38 @@ def assert_charm_supports_ipv6():
                         "versions less than Trusty 14.04")
 
 
-def get_relation_ip(interface, config_override=None):
+def get_relation_ip(interface, cidr_network=None):
-    """Return this unit's IP for the given relation.
+    """Return this unit's IP for the given interface.
 
     Allow for an arbitrary interface to use with network-get to select an IP.
-    Handle all address selection options including configuration parameter
+    Handle all address selection options including passed cidr network and
-    override and IPv6.
+    IPv6.
 
-    Usage: get_relation_ip('amqp', config_override='access-network')
+    Usage: get_relation_ip('amqp', cidr_network='10.0.0.0/8')
 
     @param interface: string name of the relation.
-    @param config_override: string name of the config option for network
+    @param cidr_network: string CIDR Network to select an address from.
-           override. Supports legacy network override configuration parameters.
     @raises Exception if prefer-ipv6 is configured but IPv6 unsupported.
     @returns IPv6 or IPv4 address
     """
+    # Select the interface address first
+    # For possible use as a fallback bellow with get_address_in_network
+    try:
+        # Get the interface specific IP
+        address = network_get_primary_address(interface)
+    except NotImplementedError:
+        # If network-get is not available
+        address = get_host_ip(unit_get('private-address'))
 
-    fallback = get_host_ip(unit_get('private-address'))
     if config('prefer-ipv6'):
+        # Currently IPv6 has priority, eventually we want IPv6 to just be
+        # another network space.
         assert_charm_supports_ipv6()
         return get_ipv6_addr()[0]
-    elif config_override and config(config_override):
+    elif cidr_network:
-        return get_address_in_network(config(config_override),
+        # If a specific CIDR network is passed get the address from that
-                                      fallback)
+        # network.
-    else:
+        return get_address_in_network(cidr_network, address)
-        try:
+
-            return network_get_primary_address(interface)
+    # Return the interface address
-        except NotImplementedError:
+    return address
-            return fallback

tests/charmhelpers/contrib/openstack/amulet/utils.py

@@ -547,7 +547,7 @@ class OpenStackAmuletUtils(AmuletUtils):
         """Create the specified instance."""
         self.log.debug('Creating instance '
                        '({}|{}|{})'.format(instance_name, image_name, flavor))
-        image = nova.images.find(name=image_name)
+        image = nova.glance.find_image(image_name)
         flavor = nova.flavors.find(name=flavor)
         instance = nova.servers.create(name=instance_name, image=image,
                                        flavor=flavor)

tests/charmhelpers/core/host.py

@@ -191,7 +191,7 @@ def service_pause(service_name, init_dir="/etc/init", initd_dir="/etc/init.d",
     upstart_file = os.path.join(init_dir, "{}.conf".format(service_name))
     sysv_file = os.path.join(initd_dir, service_name)
     if init_is_systemd():
-        service('disable', service_name)
+        service('mask', service_name)
     elif os.path.exists(upstart_file):
         override_path = os.path.join(
             init_dir, '{}.override'.format(service_name))
@@ -224,7 +224,7 @@ def service_resume(service_name, init_dir="/etc/init",
     upstart_file = os.path.join(init_dir, "{}.conf".format(service_name))
     sysv_file = os.path.join(initd_dir, service_name)
     if init_is_systemd():
-        service('enable', service_name)
+        service('unmask', service_name)
     elif os.path.exists(upstart_file):
         override_path = os.path.join(
             init_dir, '{}.override'.format(service_name))