[Zope3-checkins] CVS: Zope3/src/zodb/storage/tests - test_autopack.py:1.15

Barry Warsaw barry@zope.com
Wed, 2 Jul 2003 18:38:17 -0400


Update of /cvs-repository/Zope3/src/zodb/storage/tests
In directory cvs.zope.org:/tmp/cvs-serv4233

Modified Files:
	test_autopack.py 
Log Message:
As with the minimal tests, the full storage race condition tests can't
possibly work any more, so let's just remove the whole mess.


=== Zope3/src/zodb/storage/tests/test_autopack.py 1.14 => 1.15 ===
--- Zope3/src/zodb/storage/tests/test_autopack.py:1.14	Thu Jun 26 13:56:33 2003
+++ Zope3/src/zodb/storage/tests/test_autopack.py	Wed Jul  2 18:38:13 2003
@@ -255,267 +255,6 @@
 
 
 
-class RaceConditionBase(BerkeleyTestBase):
-    def setUp(self):
-        BerkeleyTestBase.setUp(self)
-        self._cv = threading.Condition()
-        self._storage.cv = self._cv
-
-    def tearDown(self):
-        # clean up any outstanding transactions
-        get_transaction().abort()
-        BerkeleyTestBase.tearDown(self)
-
-    def _getPackThread(self, storage):
-        raise NotImplementedError
-
-    def testRaceCondition(self):
-        unless = self.failUnless
-        storage = self._storage
-        db = DB(storage)
-        conn = db.open()
-        root = conn.root()
-        # Start by storing a root reachable object.
-        obj1 = C()
-        obj1.value = 888
-        root.obj1 = obj1
-        txn = get_transaction()
-        txn.note('root -> obj1')
-        txn.commit()
-        # Now, start a transaction, store an object, but don't yet complete
-        # the transaction.  This will ensure that the second object has a tid
-        # < packtime, but it won't be root reachable yet.
-        obj2 = C()
-        t = Transaction()
-        storage.tpcBegin(t)
-        data, refs = zodb_pickle(obj2)
-        obj2sn = storage.store('\0'*7 + '\2', ZERO, data, refs, '', t)
-        # Now, acquire the condvar lock and start a thread that will do a
-        # pack, up to the _sweep call.  Wait for the _mark() call to
-        # complete.
-        snooze()
-        self._cv.acquire()
-        packthread = self._getPackThread(storage)
-        packthread.start()
-        self._cv.wait()
-        # Now that the _mark() has finished, complete the transaction, which
-        # links the object to root.
-        root.obj2 = obj2
-        rootsn = storage.getSerial(ZERO)
-        data, refs = zodb_pickle(root)
-        rootsn = storage.store(ZERO, rootsn, data, refs, '', t)
-        storage.tpcVote(t)
-        storage.tpcFinish(t)
-        # And notify the pack thread that it can do the sweep and collect
-        self._cv.notify()
-        self._cv.wait()
-        # We're done with the condvar and the thread
-        self._cv.release()
-        packthread.join()
-        # Now make sure that all the interesting objects are still available
-        rootsn = storage.getSerial(ZERO)
-        obj1sn = storage.getSerial('\0'*7 + '\1')
-        obj2sn = storage.getSerial('\0'*7 + '\2')
-        # obj1 revision was written before the second revision of the root
-        unless(obj1sn < rootsn)
-        unless(rootsn == obj2sn)
-        unless(obj1sn < obj2sn)
-
-    def testEarlierRaceCondition(self):
-        unless = self.failUnless
-        storage = self._storage
-        db = DB(storage)
-        conn = db.open()
-        root = conn.root()
-        # Start by storing a root reachable object.
-        obj1 = C()
-        obj1.value = 888
-        root.obj1 = obj1
-        txn = get_transaction()
-        txn.note('root -> obj1')
-        txn.commit()
-        # Now, start a transaction, store an object, but don't yet complete
-        # the transaction.  This will ensure that the second object has a tid
-        # < packtime, but it won't be root reachable yet.
-        obj2 = C()
-        t = Transaction()
-        storage.tpcBegin(t)
-        # Now, acquire the condvar lock and start a thread that will do a
-        # pack, up to the _sweep call.  Wait for the _mark() call to
-        # complete.
-        snooze()
-        self._cv.acquire()
-        packthread = self._getPackThread(storage)
-        packthread.start()
-        self._cv.wait()
-        data, refs = zodb_pickle(obj2)
-        obj2sn = storage.store('\0'*7 + '\2', ZERO, data, refs, '', t)
-        # Now that the _mark() has finished, complete the transaction, which
-        # links the object to root.
-        root.obj2 = obj2
-        rootsn = storage.getSerial(ZERO)
-        data, refs = zodb_pickle(root)
-        rootsn = storage.store(ZERO, rootsn, data, refs, '', t)
-        storage.tpcVote(t)
-        storage.tpcFinish(t)
-        # And notify the pack thread that it can do the sweep and collect
-        self._cv.notify()
-        self._cv.wait()
-        # We're done with the condvar and the thread
-        self._cv.release()
-        packthread.join()
-        # Now make sure that all the interesting objects are still available
-        rootsn = storage.getSerial(ZERO)
-        obj1sn = storage.getSerial('\0'*7 + '\1')
-        obj2sn = storage.getSerial('\0'*7 + '\2')
-        # obj1 revision was written before the second revision of the root
-        unless(obj1sn < rootsn)
-        unless(rootsn == obj2sn)
-        unless(obj1sn < obj2sn)
-
-
-
-# Subclass which does ugly things to _dopack so we can actually test the race
-# condition.  We need to store a new object in the database between the
-# _mark() call and the _sweep() call.
-class SynchronizedFullStorage(BDBFullStorage):
-    # XXX Cut and paste copy from BDBFullStorage, except where indicated
-    def _dopack(self, t, gc=True):
-        # t is a TimeTime, or time float, convert this to a TimeStamp object,
-        # using an algorithm similar to what's used in FileStorage.  We know
-        # that our transaction ids, a.k.a. revision ids, are timestamps.
-        #
-        # BAW: should a pack time in the future be a ValueError?  We'd have to
-        # worry about clock skew, so for now, we just set the pack time to the
-        # minimum of t and now.
-        packtime = min(t, time.time())
-        t0 = TimeStamp(*(time.gmtime(packtime)[:5] + (packtime % 60,)))
-        packtid = `t0`
-        # Collect all revisions of all objects earlier than the pack time.
-        self._lock_acquire()
-        try:
-            self._withtxn(self._collect_revs, packtid)
-        finally:
-            self._lock_release()
-        # Collect any objects with refcount zero.
-        self._lock_acquire()
-        try:
-            self._withtxn(self._collect_objs)
-        finally:
-            self._lock_release()
-        # If we're not doing a classic pack, we're done.
-        if not gc:
-            return
-        # Do a mark and sweep for garbage collection.  Calculate the set of
-        # objects reachable from the root.  Anything else is a candidate for
-        # having all their revisions packed away.  The set of reachable
-        # objects lives in the _packmark table.
-        self._lock_acquire()
-        try:
-            self._withtxn(self._mark, packtid)
-        finally:
-            self._lock_release()
-        # XXX thread coordination code start
-        self.cv.acquire()
-        self.cv.notify()
-        self.cv.wait()
-        # XXX thread coordination code stop
-        #
-        # Now perform a sweep, using oidqueue to hold all object ids for
-        # objects which are not root reachable as of the pack time.
-        self._lock_acquire()
-        try:
-            self._withtxn(self._sweep, packtid)
-        finally:
-            self._lock_release()
-        # Once again, collect any objects with refcount zero due to the mark
-        # and sweep garbage collection pass.
-        self._lock_acquire()
-        try:
-            self._withtxn(self._collect_objs)
-        finally:
-            self._lock_release()
-        # XXX thread coordination code start
-        self.cv.notify()
-        self.cv.release()
-        # XXX thread coordination code stop
-
-
-class FullPackThread(threading.Thread):
-    def __init__(self, storage):
-        threading.Thread.__init__(self)
-        self._storage = storage
-
-    def run(self):
-        self._storage.pack(time.time(), gc=True)
-
-
-class TestFullClassicPackRaceCondition(RaceConditionBase):
-    ConcreteStorage = SynchronizedFullStorage
-
-    def _getPackThread(self, storage):
-        return FullPackThread(storage)
-
-
-
-# Subclass which does ugly things to _dopack so we can actually test the race
-# condition.  We need to storage a new object in the database between the
-# _mark() call and the _sweep() call.
-class SynchronizedMinimalStorage(BDBMinimalStorage):
-    # XXX Cut and paste copy from BDBMinimalStorage, except where indicated
-    def _dopack(self):
-        # Do a mark and sweep for garbage collection.  Calculate the set of
-        # objects reachable from the root.  Anything else is a candidate for
-        # having all their revisions packed away.  The set of reachable
-        # objects lives in the _packmark table.
-        self._lock_acquire()
-        try:
-            self._withtxn(self._mark)
-        finally:
-            self._lock_release()
-        # XXX thread coordination code start
-        self.cv.acquire()
-        self.cv.notify()
-        self.cv.wait()
-        # XXX thread coordination code stop
-        #
-        # Now perform a sweep, using oidqueue to hold all object ids for
-        # objects which are not root reachable as of the pack time.
-        self._lock_acquire()
-        try:
-            self._withtxn(self._sweep)
-        finally:
-            self._lock_release()
-        # Once again, collect any objects with refcount zero due to the mark
-        # and sweep garbage collection pass.
-        self._lock_acquire()
-        try:
-            self._withtxn(self._collect_objs)
-        finally:
-            self._lock_release()
-        # XXX thread coordination code start
-        self.cv.notify()
-        self.cv.release()
-        # XXX thread coordination code stop
-
-
-class MinimalPackThread(threading.Thread):
-    def __init__(self, storage):
-        threading.Thread.__init__(self)
-        self._storage = storage
-
-    def run(self):
-        self._storage.pack(time.time())
-
-
-class TestMinimalClassicPackRaceCondition(RaceConditionBase):
-    ConcreteStorage = SynchronizedMinimalStorage
-
-    def _getPackThread(self, storage):
-        return MinimalPackThread(storage)
-
-
-
 def test_suite():
     suite = unittest.TestSuite()
     suite.level = 2
@@ -523,13 +262,6 @@
         suite.addTest(unittest.makeSuite(TestAutopack))
         suite.addTest(unittest.makeSuite(TestAutomaticClassicPack))
         suite.addTest(unittest.makeSuite(TestMinimalPack))
-        suite.addTest(unittest.makeSuite(TestFullClassicPackRaceCondition))
-        # These tests cannot work for minimal storage with the new locking
-        # regime.  The test purposefully does not complete the in-progress
-        # transaction until pack reaches the mark phase, which it can't do
-        # because the outer pack() call tries to acquire the commit lock,
-        # which /it/ can't get.
-        #suite.addTest(unittest.makeSuite(TestMinimalClassicPackRaceCondition))
     return suite