From 320ef645c84fbebdfd216574f0ff1b5623b26acc Mon Sep 17 00:00:00 2001
From: John Tran <jhtran@att.com>
Date: Wed, 24 Oct 2012 00:06:53 +0000
Subject: [PATCH] Fix sqlalchemy performance problem

Fixes bug #1070074 too much lazy loading on the
default model.  Removed those and only added lazy
loading to queries that specifically need eager
loading

Change-Id: Ifa7446bddef855ae8e8b76040ba3336a53606215
---
 ceilometer/storage/impl_sqlalchemy.py    | 11 ++++++-----
 ceilometer/storage/sqlalchemy/models.py  | 22 +++++++++-------------
 ceilometer/storage/sqlalchemy/session.py |  5 -----
 3 files changed, 15 insertions(+), 23 deletions(-)

diff --git a/ceilometer/storage/impl_sqlalchemy.py b/ceilometer/storage/impl_sqlalchemy.py
index 14dc0084b..ddf5e00c1 100644
--- a/ceilometer/storage/impl_sqlalchemy.py
+++ b/ceilometer/storage/impl_sqlalchemy.py
@@ -24,8 +24,7 @@ from ceilometer.openstack.common import cfg
 from ceilometer.storage import base
 from ceilometer.storage.sqlalchemy.models import Meter, Project, Resource
 from ceilometer.storage.sqlalchemy.models import Source, User
-from ceilometer.storage.sqlalchemy.session import get_session
-import ceilometer.storage.sqlalchemy.session as session
+import ceilometer.storage.sqlalchemy.session as sqlalchemy_session
 
 LOG = log.getLogger(__name__)
 
@@ -109,7 +108,7 @@ class Connection(base.Connection):
     def _get_connection(self, conf):
         """Return a connection to the database.
         """
-        return session.get_session()
+        return sqlalchemy_session.get_session()
 
     def record_metering_data(self, data):
         """Write the data to the backend storage system.
@@ -222,6 +221,8 @@ class Connection(base.Connection):
             query = query.filter(Resource.timestamp < end_timestamp)
         if project is not None:
             query = query.filter(Resource.project_id == project)
+        query = query.options(
+                    sqlalchemy_session.sqlalchemy.orm.joinedload('meters'))
 
         for resource in query.all():
             r = row2dict(resource)
@@ -262,7 +263,7 @@ class Connection(base.Connection):
 
         ( datetime.datetime(), datetime.datetime() )
         """
-        func = session.func()
+        func = sqlalchemy_session.sqlalchemy.func
         query = self.session.query(func.min(Meter.timestamp),
                                    func.max(Meter.timestamp))
         query = make_query_from_filter(query, event_filter)
@@ -279,7 +280,7 @@ def model_query(*args, **kwargs):
 
     :param session: if present, the session to use
     """
-    session = kwargs.get('session') or get_session()
+    session = kwargs.get('session') or sqlalchemy_session.get_session()
     query = session.query(*args)
     return query
 
diff --git a/ceilometer/storage/sqlalchemy/models.py b/ceilometer/storage/sqlalchemy/models.py
index 00eb5b28c..953dcaa9d 100644
--- a/ceilometer/storage/sqlalchemy/models.py
+++ b/ceilometer/storage/sqlalchemy/models.py
@@ -96,8 +96,7 @@ class Meter(Base):
     __tablename__ = 'meter'
     id = Column(Integer, primary_key=True)
     counter_name = Column(String(255))
-    sources = relationship("Source", secondary=lambda: sourceassoc,
-                           lazy='joined')
+    sources = relationship("Source", secondary=lambda: sourceassoc)
     user_id = Column(String(255), ForeignKey('user.id'))
     project_id = Column(String(255), ForeignKey('project.id'))
     resource_id = Column(String(255), ForeignKey('resource.id'))
@@ -112,29 +111,26 @@ class Meter(Base):
 class User(Base):
     __tablename__ = 'user'
     id = Column(String(255), primary_key=True)
-    sources = relationship("Source", secondary=lambda: sourceassoc,
-                           lazy='joined')
-    resources = relationship("Resource", backref='user', lazy='joined')
-    meters = relationship("Meter", backref='user', lazy='joined')
+    sources = relationship("Source", secondary=lambda: sourceassoc)
+    resources = relationship("Resource", backref='user')
+    meters = relationship("Meter", backref='user')
 
 
 class Project(Base):
     __tablename__ = 'project'
     id = Column(String(255), primary_key=True)
-    sources = relationship("Source", secondary=lambda: sourceassoc,
-                           lazy='joined')
-    resources = relationship("Resource", backref='project', lazy='joined')
-    meters = relationship("Meter", backref='project', lazy='joined')
+    sources = relationship("Source", secondary=lambda: sourceassoc)
+    resources = relationship("Resource", backref='project')
+    meters = relationship("Meter", backref='project')
 
 
 class Resource(Base):
     __tablename__ = 'resource'
     id = Column(String(255), primary_key=True)
-    sources = relationship("Source", secondary=lambda: sourceassoc,
-                           lazy='joined')
+    sources = relationship("Source", secondary=lambda: sourceassoc)
     timestamp = Column(DateTime)
     resource_metadata = Column(JSONEncodedDict)
     received_timestamp = Column(DateTime, default=timeutils.utcnow)
     user_id = Column(String(255), ForeignKey('user.id'))
     project_id = Column(String(255), ForeignKey('project.id'))
-    meters = relationship("Meter", backref='resource', lazy='joined')
+    meters = relationship("Meter", backref='resource')
diff --git a/ceilometer/storage/sqlalchemy/session.py b/ceilometer/storage/sqlalchemy/session.py
index db2bc5a2d..858037c14 100644
--- a/ceilometer/storage/sqlalchemy/session.py
+++ b/ceilometer/storage/sqlalchemy/session.py
@@ -189,8 +189,3 @@ def get_maker(engine, autocommit=True, expire_on_commit=False, autoflush=True):
                                        autocommit=autocommit,
                                        autoflush=autoflush,
                                        expire_on_commit=expire_on_commit)
-
-
-def func():
-    # ugly hack sqlalchemy name conflict from impl_sqlalchemy
-    return sqlalchemy.func