WARNING: Packing is dangerous!!! (zope <= 2.6.1)
Sorry for the caps in the subject, but it seems this bug is not nearly well publicized enough.* People keep stumbling onto this bug on their own and writing to the list about it. In Zope 2.6.1, 2.6.0, and probably 2.5.x at least: Packing a FileStorage (Data.fs) can lead to some loss of data. http://collector.zope.org/Zope/875 In addition, the "fsrecover.py" script that ships with Zope 2.6.1 is broken - it (often? always?) produces a nearly-empty Data.fs. If you need it, use fsrecover.py from CVS or from Zope 2.6.0. Considering how much of the existing documentation recommends frequent packing to maintain a healthy Data.fs, I think it would be advisable for Zope corp. to take steps to alert users to this very serious problem. Irrecoverable data loss is the kind of thing that ruins software reputation. Maybe a news item on zope.org? In addition, I think it's a critical enough problem that when a solution is found, there should be published hotfixes for 2.6.1 and 2.6.0 at least. -- Paul Winkler home: http://www.slinkp.com "Muppet Labs, where the future is made - today!"
Sorry for the caps in the subject, but it seems this bug is not nearly well publicized enough.* People keep stumbling onto this bug on their own and writing to the list about it.
In Zope 2.6.1, 2.6.0, and probably 2.5.x at least: Packing a FileStorage (Data.fs) can lead to some loss of data. http://collector.zope.org/Zope/875
Jeremy (the ZODB pope) will be looking at this tomorrow (he is out today). It appears that we have an easily reproducable recipe, so he should be able to give some guidance on this fairly quickly. Brian Lloyd brian@zope.com V.P. Engineering 540.361.1716 Zope Corporation http://www.zope.com
Paul Winkler wrote:
Sorry for the caps in the subject, but it seems this bug is not nearly well publicized enough.* People keep stumbling onto this bug on their own and writing to the list about it.
In Zope 2.6.1, 2.6.0, and probably 2.5.x at least: Packing a FileStorage (Data.fs) can lead to some loss of data. http://collector.zope.org/Zope/875
In addition, the "fsrecover.py" script that ships with Zope 2.6.1 is broken - it (often? always?) produces a nearly-empty Data.fs. If you need it, use fsrecover.py from CVS or from Zope 2.6.0.
Considering how much of the existing documentation recommends frequent packing to maintain a healthy Data.fs, I think it would be advisable for Zope corp. to take steps to alert users to this very serious problem. Irrecoverable data loss is the kind of thing that ruins software reputation. Maybe a news item on zope.org?
In addition, I think it's a critical enough problem that when a solution is found, there should be published hotfixes for 2.6.1 and 2.6.0 at least.
Jeremy is out today. I'm sure he'll responde when he gets back tomorrow. He's recently rewritten the packing algorithms and solved some problems that were introduced with transactional undo. It would be a good idea to test the new packing code against the cases described in the collector entry. Jim
participants (3)
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Brian Lloyd -
Jim Fulton -
Paul Winkler