[Zope] Trying to trap ConflictError

[Jonathan]

----- Original Message ----- 
From: <dieter at handshake.de>
To: "Jonathan" <dev101 at magma.ca>
Cc: "Dennis Allison" <allison at shasta.stanford.edu>; <zope at zope.org>
Sent: Wednesday, July 05, 2006 2:28 PM
Subject: Re: [Zope] Trying to trap ConflictError


> Jonathan wrote at 2006-7-4 13:46 -0400:
>> ...
>>The image objects stored in
>>TemporaryStorage are never overwritten, edited etc (which is causing me 
>>some
>>confusion as to why the conflict errors are occurring)
>
> The error message tells your that the conflict is not caused by
> the modification of the image but the container holding your image.
>
> "BTreeFolder" already do conflict resolution -- and reduce the
> conflict probability by about a factor of 30 to 100 (depending on type).
>
> However, if several threads should try to add elements with the same
> id, then the conflict resolution cannot work.
> Maybe, that happens in your case?

The id for the image object is generated by the following code:

def MakeId():
   time.sleep(.01)
   ts = string.replace(str(time.time()),'.', '')   # remove floating point 
'.' char
   return ts[-10:]

So there should not be any collision of ids.

I am still investing, and have found errors like:

2006-07-04T14:48:12 ERROR ZODB.Connection Couldn't load state for 0x1c
Traceback (most recent call last):
  File "/usr/local/Zope-2.9.2/lib/python/ZODB/Connection.py", line 732, in 
setstate
    self._setstate(obj)
  File "/usr/local/Zope-2.9.2/lib/python/ZODB/Connection.py", line 768, in 
_setstate
    p, serial = self._storage.load(obj._p_oid, self._version)
  File "/usr/local/Zope-2.9.2/lib/python/tempstorage/TemporaryStorage.py", 
line 104, in load
    s=self._index[oid]
KeyError: '\x00\x00\x00\x00\x00\x00\x00\x1c'

in the event.log.   From my googling research, it appears that these type of 
errors may be due to insufficient memory (but I am not sure and am still 
investigating to see if this is the cause of the conflict errors).

Thanks to all for the suggestions and assistance!

Jonathan