[ZODB-Dev] Commit or lock object accross transactions

[Shane Hathaway]

Roché Compaan wrote:
> * Roché Compaan <roche at upfrontsystems.co.za> [2003-07-16 20:00]:
> 
>>I am not too concerned about orphaned ids so the BTrees Length class
>>would be the simplest solution for me. You seem to have tougher
>>constraints to navigate, so good luck :-)
> 
> 
> Just some feedback. We implemented and object id service using
> BTrees.Length and I'm sorry to say that it doesn't scale very well. It's
> ok when you have 2 threads but anything above that and you can be sure
> that you will get duplicate ids.
> 
> In a test with 10 concurrent clients each continually asking for ids
> until they have a 100 ids we got 37 duplicates out of a 1000. You might
> just as well start up your Zope server single threaded :-(
> 
> Any other ideas?

Well, seriously, calling self._p_jar.new_oid() ought to work pretty 
well.  You'll only exhaust the OID space if you make 1 billion IDs per 
second consistently for the next 500 years. ;-)

Alternatively, you could add a new "sequence generator" interface to 
your ZODB storage.  It would be generally useful.

Shane