[ZODB-Dev] problem with _p_mtime

[Tres Seaver]

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Miles Waller wrote:
> Tres Seaver wrote:
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>> Miles wrote:
>>   
>>> Hi,
>>>
>>> I've moved a FileStorage from one (old) machine to another (new) 
>>> machine, but when I mount it on the new machine I get a lot of time errrors:
>>>
>>> Traceback (innermost last):
>>>    Module ZPublisher.Publish, line 115, in publish
>>>    Module ZPublisher.mapply, line 88, in mapply
>>>    Module ZPublisher.Publish, line 41, in call_object
>>>    Module Shared.DC.Scripts.Bindings, line 311, in __call__
>>>    Module Shared.DC.Scripts.Bindings, line 348, in _bindAndExec
>>>    Module App.special_dtml, line 176, in _exec
>>>    Module DocumentTemplate.DT_Let, line 76, in render
>>>    Module DocumentTemplate.DT_In, line 703, in renderwob
>>>    Module DocumentTemplate.DT_With, line 76, in render
>>>    Module DocumentTemplate.DT_Var, line 214, in render
>>>    Module App.PersistentExtra, line 43, in bobobase_modification_time
>>>    Module DateTime.DateTime, line 509, in __init__
>>>    Module DateTime.DateTime, line 760, in _parse_args
>>>    Module DateTime.DateTime, line 437, in safelocaltime
>>> TimeError: The time 98040302366.810165 is beyond the range of this 
>>> Python implementation.
>>>
>>> I googled around on this problem and didn't find much, but I did find 
>>> that as a temporary fix, I've put a try/except in App.PersistentExtra, 
>>> so if it generates an exception, it returns the current date and time. 
>>> This keeps things working.
>>>
>>> Out of interst, can anyone tell me why there is a difference?  On both 
>>> machines, python was compiled from source with the same options, so I'm 
>>> not sure what this is down to.
>>>
>>> More importantly, what's the most straightforward way to set all the 
>>> dates to usable values?  From my POV, it's fine to set them all to the 
>>> current date, but I don't know how to go about doing this exhaustively.
>>>
>>> Thanks for your help,
>>>     
>> For each machine:  what version of Python and Zope?  what OS?
>>   
> Old machine: Python 2.3.5, Zope 2.8.6, OS is Red Hat 8.0 (!)
> 
> New machine: Python 2.4.3, Zope 2.9.8, OS is Ubuntu 7.10
> 
> I had discounted python/zope version differences as other databases had 
> upgraded fine.

(CC'ing the newsgroup)

Zope is defending against a change in Python's time module, which in
turn is due to a change in the platform's time_t:

$ bin/python2.3
Python 2.3.7 (#1, Aug 20 2008, 12:39:04)
[GCC 4.2.3 (Ubuntu 4.2.3-2ubuntu7)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> int(98040302366.81016)
98040302366L
>>> from time import gmtime, localtime
>>> gmtime(int(98040302366.81016))
(1901, 12, 13, 20, 45, 52, 4, 347, 0)
>>> localtime(int(98040302366.81016))
(1901, 12, 13, 15, 45, 52, 4, 347, 0)

$ bin/python2.4
Python 2.4.4 (#2, Nov 14 2007, 13:58:47)
[GCC 4.1.2 (Ubuntu 4.1.2-0ubuntu4)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> int(98040302366.81016)
98040302366L
>>> from time import gmtime, localtime
>>> gmtime(int(98040302366.81016))
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
ValueError: timestamp out of range for platform time_t
>>> localtime(int(98040302366.81016))
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
ValueError: timestamp out of range for platform time_t


As you can see, the Python 2.3 version has a wraparound problem.  I have
no idea how you got such an odd value stored for your '_p_mtime', unless
you have been using Guido's time machine to run your appserver in 2039. ;)


Tres.
- --
===================================================================
Tres Seaver          +1 540-429-0999          tseaver at palladion.com
Palladion Software   "Excellence by Design"    http://palladion.com
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