Add swift_store_ssl_compression param

Add a new glance-api.conf parameter 'swift_store_ssl_compression',
which allows disabling SSL layer compression for https swift requests.

This can increase performance when transferring compressed images (eg
qcow2) to/from swift.

Addresses bug 1190666.

DocImpact.

Change-Id: Ic26dba9dce5ea7e5c09fdd531746b93cec54fc5c

doc/source/configuring.rst

@@ -527,6 +527,19 @@ Optional. Default: ``publicURL``
 A string giving the endpoint type of the swift service endpoint to
 use. This setting is only used if swift_store_auth_version is ``2``.
 
+* ``swift_store_ssl_compression``
+
+Can only be specified in configuration files.
+
+`This option is specific to the Swift storage backend.`
+
+Optional. Default: True.
+
+If set to False, disables SSL layer compression of https swift
+requests. Setting to 'False' may improve performance for images which
+are already in a compressed format, eg qcow2. If set to True then
+compression will be enabled (provided it is supported by the swift
+proxy).
 
 
 Configuring the S3 Storage Backend

etc/glance-api.conf

@@ -315,6 +315,12 @@ swift_enable_snet = False
 # is only necessary if the tenant has multiple swift endpoints.
 #swift_store_region =
 
+# If set to False, disables SSL layer compression of https swift requests.
+# Setting to 'False' may improve performance for images which are already
+# in a compressed format, eg qcow2. If set to True, enables SSL layer
+# compression (provided it is supported by the target swift proxy).
+#swift_store_ssl_compression = True
+
 # ============ S3 Store Options =============================
 
 # Address where the S3 authentication service lives

glance/store/swift.py

@@ -102,6 +102,11 @@ swift_opts = [
                 help=_('A list of tenants that will be granted read/write '
                        'access on all Swift containers created by Glance in '
                        'multi-tenant mode.')),
+    cfg.BoolOpt('swift_store_ssl_compression', default=True,
+                help=_('If set to False, disables SSL layer compression of '
+                       'https swift requests. Setting to False may improve '
+                       'performance for images which are already in a '
+                       'compressed format, eg qcow2.')),
 ]
 
 CONF = cfg.CONF
@@ -267,6 +272,7 @@ class BaseStore(glance.store.base.Store):
         self.endpoint_type = CONF.swift_store_endpoint_type
         self.snet = CONF.swift_enable_snet
         self.insecure = CONF.swift_store_auth_insecure
+        self.ssl_compression = CONF.swift_store_ssl_compression
 
     def get(self, location, connection=None):
         location = location.store_location
@@ -574,7 +580,8 @@ class SingleTenantStore(BaseStore):
         return swiftclient.Connection(
                 auth_url, user, location.key, insecure=self.insecure,
                 tenant_name=tenant_name, snet=self.snet,
-                auth_version=self.auth_version, os_options=os_options)
+                auth_version=self.auth_version, os_options=os_options,
+                ssl_compression=self.ssl_compression)
 
 
 class MultiTenantStore(BaseStore):
@@ -654,7 +661,8 @@ class MultiTenantStore(BaseStore):
                 preauthurl=location.swift_url,
                 preauthtoken=self.context.auth_tok,
                 tenant_name=self.context.tenant,
-                auth_version='2', snet=self.snet, insecure=self.insecure)
+                auth_version='2', snet=self.snet, insecure=self.insecure,
+                ssl_compression=self.ssl_compression)
 
 
 class ChunkReader(object):

glance/tests/unit/test_swift_store.py

@@ -692,7 +692,7 @@ class FakeConnection(object):
     def __init__(self, authurl, user, key, retries=5, preauthurl=None,
                  preauthtoken=None, snet=False, starting_backoff=1,
                  tenant_name=None, os_options={}, auth_version="1",
-                 insecure=False):
+                 insecure=False, ssl_compression=True):
         self.authurl = authurl
         self.user = user
         self.key = key

requirements.txt

@@ -25,7 +25,7 @@ iso8601>=0.1.4
 oslo.config>=1.2.0a3
 
 # For Swift storage backend.
-python-swiftclient>=1.2
+python-swiftclient>=1.5
 
 # Note you will need gcc buildtools installed and must
 # have installed libxml headers for lxml to be successfully