[Zope-Checkins] CVS: Zope/lib/python/Products/Transience -
Transience.py:1.32.12.5
Chris McDonough
chrism at plope.com
Wed May 19 20:57:22 EDT 2004
Update of /cvs-repository/Zope/lib/python/Products/Transience
In directory cvs.zope.org:/tmp/cvs-serv15317
Modified Files:
Tag: Zope-2_7-branch
Transience.py
Log Message:
- Simple parameterization of BUCKET_CLASS for testing/debugging purposes.
BUCKET_CLASS can be set to something like "dict" in order to isolate
future problems potentially caused by OOBTrees (not that there seem
to be any, but it's nice to be able to confirm).
- Log at INFO level in TLOG instead of BLATHER.
- Fix "off by one" error in _getCurrentSlices and explain.
- Add various DEBUG and TLOG statements for testing/debugging purposes.
- Arrange to compare against "default" instead of "_marker" in .get.
- Use random.uniform instead of random.choice to decide how to sleep.
- Use "_wrap" instead of directly calling __of__ for consistency.
=== Zope/lib/python/Products/Transience/Transience.py 1.32.12.4 => 1.32.12.5 ===
--- Zope/lib/python/Products/Transience/Transience.py:1.32.12.4 Sat May 15 14:03:17 2004
+++ Zope/lib/python/Products/Transience/Transience.py Wed May 19 20:57:21 2004
@@ -43,7 +43,7 @@
from AccessControl.SecurityManagement import newSecurityManager, \
setSecurityManager
from AccessControl.User import nobody
-from zLOG import LOG, WARNING, BLATHER
+from zLOG import LOG, WARNING, INFO
from TransientObject import TransientObject
@@ -54,8 +54,9 @@
ACCESS_TRANSIENTS_PERM = 'Access Transient Objects'
MANAGE_CONTAINER_PERM = 'Manage Transient Object Container'
-PERIOD = 20 # signifies "resolution" of transience machinery
-SPARE_BUCKETS = 15 # number of buckets to keep spare
+PERIOD = 20 # signifies "resolution" of transience machinery in seconds
+SPARE_BUCKETS = 15 # minimum number of buckets to keep "spare"
+BUCKET_CLASS = OOBTree # constructor for buckets
STRICT = os.environ.get('Z_TOC_STRICT', '')
DEBUG = int(os.environ.get('Z_TOC_DEBUG', 0))
@@ -73,7 +74,7 @@
for arg in args:
sargs.append(str(arg))
msg = ' '.join(sargs)
- LOG('Transience', BLATHER, msg)
+ LOG('Transience', INFO, msg)
constructTransientObjectContainerForm = HTMLFile(
'dtml/addTransientObjectContainer', globals())
@@ -174,11 +175,11 @@
if self._timeout_slices:
new_slices = getTimeslices(getCurrentTimeslice(), SPARE_BUCKETS*2)
for i in new_slices:
- self._data[i] = OOBTree()
+ self._data[i] = BUCKET_CLASS()
# create an Increaser for max timeslice
self._max_timeslice = Increaser(max(new_slices))
else:
- self._data[0] = OOBTree() # sentinel value for non-expiring data
+ self._data[0] = BUCKET_CLASS() # sentinel value for non-expiring
self._max_timeslice = Increaser(0)
# our "_length" is the length of _index.
@@ -189,10 +190,19 @@
def _getCurrentSlices(self, now):
if self._timeout_slices:
- begin = now+PERIOD - (PERIOD * self._timeout_slices)
- num_slices = self._timeout_slices
+ begin = now - (PERIOD * self._timeout_slices)
+ # add add one to _timeout_slices below to account for the fact that
+ # a call to this method may happen any time within the current
+ # timeslice; calling it in the beginning of the timeslice can lead
+ # to sessions becoming invalid a maximum of <PERIOD> seconds
+ # earlier than the requested timeout value. Adding one here can
+ # lead to sessions becoming invalid *later* than the timeout value
+ # (also by a max of <PERIOD>), but in the common sessioning case,
+ # that seems preferable.
+ num_slices = self._timeout_slices + 1
else:
return [0] # sentinel for timeout value 0 (don't expire)
+ DEBUG and TLOG('_getCurrentSlices, now = %s ' % now)
DEBUG and TLOG('_getCurrentSlices, begin = %s' % begin)
DEBUG and TLOG('_getCurrentSlices, num_slices = %s' % num_slices)
result = getTimeslices(begin, num_slices)
@@ -220,20 +230,53 @@
for ts in current:
bucket = self._data.get(ts)
+ DEBUG and TLOG(
+ '_move_item: bucket for ts %s is %s' % (ts, id(bucket)))
# dont use hasattr here (it hides conflict errors)
- if getattr(bucket, 'has_key', None) and bucket.has_key(k):
- found_ts = ts
- break
+ if getattr(bucket, 'has_key', None):
+ if DEBUG:
+ keys = list(bucket.keys())
+ DEBUG and TLOG(
+ '_move_item: keys for ts %s (bucket %s)-- %s' %
+ (ts, id(bucket), str(keys))
+ )
+ if bucket.has_key(k):
+ found_ts = ts
+ break
+ DEBUG and TLOG('_move_item: found_ts is %s' % found_ts)
if found_ts is None:
+ DEBUG and TLOG('_move_item: returning default of %s' % default)
return default
bucket = self._data[found_ts]
item = bucket[k]
if current_ts != found_ts:
+ DEBUG and TLOG(
+ '_move_item: moving item %s from %s to %s' % (
+ k, found_ts, current_ts))
del bucket[k]
- self._data[current_ts][k] = item
+ if not issubclass(BUCKET_CLASS, Persistent):
+ # tickle persistence machinery
+ self._data[found_ts] = bucket
+ DEBUG and TLOG(
+ '_move_item: deleted key %s from bucket %s' % (
+ k,id(bucket))
+ )
+ if DEBUG:
+ keys = list(bucket.keys())
+ DEBUG and TLOG(
+ '_move_item: keys for found_ts %s (bucket %s): %s' % (
+ found_ts, id(bucket), str(keys))
+ )
+ STRICT and _assert(bucket.get(k, None) is None)
+ STRICT and _assert(not bucket.has_key(k))
+ current_bucket = self._data[current_ts]
+ current_bucket[k] = item
+ if not issubclass(BUCKET_CLASS, Persistent):
+ # tickle persistence machinery
+ self._data[current_ts] = current_bucket
else:
# special case for no timeout value
@@ -321,6 +364,7 @@
return self._wrap(item)
def __setitem__(self, k, v):
+ DEBUG and TLOG('__setitem__: called with key %s, value %s' % (k,v))
if self._timeout_slices:
current_ts = getCurrentTimeslice()
else:
@@ -338,8 +382,13 @@
"%s exceeds maximum number of subobjects %s" %
(len(self), self._limit))
self._length.change(1)
+ DEBUG and TLOG('__setitem__: placing value for key %s in bucket %s' %
+ (k, current_ts))
current_bucket = self._data[current_ts]
current_bucket[k] = v
+ if not issubclass(BUCKET_CLASS, Persistent):
+ # tickle persistence machinery
+ self._data[current_ts] = current_bucket
self.notifyAdd(v)
# change the TO's last accessed time
# dont use hasattr here (it hides conflict errors)
@@ -347,13 +396,18 @@
v.setLastAccessed()
def __delitem__(self, k):
+ DEBUG and TLOG('__delitem__ called with key %s' % k)
if self._timeout_slices:
current_ts = getCurrentTimeslice()
else:
current_ts = 0
item = self._move_item(k, current_ts)
STRICT and _assert(self._data.has_key(current_ts))
- del self._data[current_ts][k]
+ bucket = self._data[current_ts]
+ del bucket[k]
+ if not issubclass(BUCKET_CLASS, Persistent):
+ # tickle persistence machinery
+ self._data[current_ts] = bucket
self._length.change(-1)
return current_ts, item
@@ -362,13 +416,15 @@
security.declareProtected(ACCESS_TRANSIENTS_PERM, 'get')
def get(self, k, default=None):
+ DEBUG and TLOG('get: called with key %s, default %s' % (k, default))
if self._timeout_slices:
current_ts = getCurrentTimeslice()
else:
current_ts = 0
- item = self._move_item(k, current_ts, _marker)
+ item = self._move_item(k, current_ts, default)
STRICT and _assert(self._data.has_key(current_ts))
- if item is _marker:
+ if item is default:
+ DEBUG and TLOG('get: returning default')
return default
return self._wrap(item)
@@ -378,10 +434,14 @@
current_ts = getCurrentTimeslice()
else:
current_ts = 0
+ DEBUG and TLOG('has_key: calling _move_item with %s' % str(k))
item = self._move_item(k, current_ts, _marker)
+ DEBUG and TLOG('has_key: _move_item returned %s%s' %
+ (item, item is _marker and ' (marker)' or ''))
STRICT and _assert(self._data.has_key(current_ts))
if item is not _marker:
return True
+ DEBUG and TLOG('has_key: returning false from for %s' % k)
return False
def _roll(self, now, reason):
@@ -451,10 +511,10 @@
for k in new_buckets:
STRICT and _assert(not self._data.has_key(k))
try:
- self._data[k] = OOBTree()
+ self._data[k] = BUCKET_CLASS()
except ConflictError:
DEBUG and TLOG('_replentish: conflict when adding %s' % k)
- time.sleep(random.choice([0.1, 0.2, 0.3])) # add entropy
+ time.sleep(random.uniform(0, 1)) # add entropy
raise
self._max_timeslice.set(max(new_buckets))
@@ -468,6 +528,9 @@
to_notify = []
+ DEBUG and TLOG('_gc: now is %s' % now)
+ DEBUG and TLOG('_gc: max_ts is %s' % max_ts)
+
for key in list(self._data.keys(None, max_ts)):
assert(key <= max_ts)
STRICT and _assert(self._data.has_key(key))
@@ -476,6 +539,7 @@
to_notify.append(v)
self._length.change(-1)
+ DEBUG and TLOG('deleting %s from _data' % key)
del self._data[key]
for v in to_notify:
@@ -552,7 +616,7 @@
if item is _marker:
item = TransientObject(key)
self[key] = item
- item = item.__of__(self)
+ item = self._wrap(item)
return item
security.declareProtected(CREATE_TRANSIENTS_PERM, 'new')
@@ -564,7 +628,7 @@
raise KeyError, "cannot duplicate key %s" % key
item = TransientObject(key)
self[key] = item
- return item.__of__(self)
+ return self._wrap(item)
# TransientItemContainer methods
@@ -644,7 +708,7 @@
new_slices = getTimeslices(getCurrentTimeslice(), SPARE_BUCKETS*2)
for i in new_slices:
if not self._data.has_key(i):
- self._data[i] = OOBTree()
+ self._data[i] = BUCKET_CLASS()
# create an Increaser for max timeslice
self._max_timeslice = Increaser(max(new_slices))
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