Collector 1900.

send_reply(), return_error():  Stop trying to catch an exception that doesn't
exist, when marshal.encode() raises an exception.  Jeremy simplified the
marshal.encode() half of this about 3 years ago, but apparently forgot to
change ZEO/zrpc/connection.py to match.

transactions for users defined in a non-root acl_users folder. Zope logs a
acl_users path together with a username (separated by a space) and this
previous fix failed to take this into account. Fixed by taking anything after
the last space in the compared path out of the equation.

release from the 3.4 branch.

Collector 1873.

update_from_seq():  If PySequence_Check(seq) returns true,
go on to check for the existence of "iteritems" when deciding
whether the input is or is not "a sequence".  Alas,
PySequence_Check() does return true for PersistentMapping and
PersistentDict instances, so that they couldn't be used as
arguments to BTree/Bucket construction or update().

This is nasty type-sniffing, but it was before too.  There's
no way to make such stuff bulletproof, so I'm settling for
incremental improvement.

storage interfaces.  It would be better to define &
document them, but that takes time, and until time is
available better not to pretend that they're all really
part of "the" storage API.

Also gave it some tests (it was woefully untested).

this helps poor schmucks like me who have to make app-level conflict resolution
work in Products as well. Including INSTANCE_HOME makes sure ZEO can find the
product code in the first place.

simul.py hit NameErrors when startup cache verification
found data in the cache to invalidate.

The cache's loadBefore() implementation called _trace()
incorrectly, passing the tid where the version argument
belonged.

Add missing packaging files, for zpkg use.

There's no possiblity of rollback here, so no need to insist that the
data manager support rollbacks.

ClientCache._evicted():  When deleting the last range of
non-current tids for an oid, remove the list from the
noncurrent dict instead of leaving an empty list sitting
there forever.  This also required adjusting the side-
effect dance in ClientCache._remove_noncurrent_revisions().

FileCache._makeroom():  This was the major leak -- it
neglected to remove an evicted object's Entry from the
key2entry dict.

  Merge the philikon-zeo-scripts branch:
    move things around so that zeo scripts are installed for
    standalone zodb releases but not for zope releases

See the thread starting at
 http://mail.zope.org/pipermail/zope/2005-July/160433.html
for gory details.

Maintaining this is a significant expense; the code didn't
make real use of it; and every time I've tried to exploit it
I've ended up with grossly too-large simulated hit rates.
Would probably take another day to figure out exactly why that
is, and the simulated rates are "good enough" now without it.

although the toy app I wrote to generate a 500MB trace
file doesn't use MVCC in an essential way (some of the
MVCC simulation code is nevertheless exercised, since
an invalidation of current data in the presence of MVCC
always creates a cache record for the newly non-current
revision).

Still puzzling over what to do when the trace file records
a load hit but the simulated cache gets a miss.  The
old simulation code seemed to assume that a store for the same
oid would show up in the trace file next, and it could get
the info it needed about the missing object from the store
trace.  But that isn't true:  precisely because the load was
a hit in the trace file, the object isn't going to be stored
again "soon" in the trace file.

Here are some actual-vs-simulated hit rate results, for a
20MB cache, with a trace file covering about 9 million
loads, over 3 ZEO client (re)starts:

actual   simulated
------   ---------
  93.1        92.7
  79.8        79.0
  68.0        69.1
      
  81.4        81.1  overall

Since the simulated hit rates are both higher and lower
than the actual hit rates, that argues against a gross
systematic bias in the simulation (although there may
be several systematic biases in opposite directions).

MVCC.  It isn't blowing up, but it thinks the hit rate is
100% -- might have missed something there <wink>.

I think the primary hangup now is that simul.py doesn't know
anything about MVCC.  As a result, it thinks there's significatly
more free space in the cache than there really is, and that
probably accounts for it predicting significantly higher hit
rates than I actually see.

Output isn't obviously wholly insane, but isn't a reasonably
close enough match to stats.py output either yet.