[Buildbot] #2656: [nine] Reduce schedulers' stored state

[Buildbot trac]

#2656: [nine] Reduce schedulers' stored state
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Reporter:  dustin  |       Owner:
    Type:  task    |      Status:  new
Priority:  major   |   Milestone:  0.9.0
 Version:          |  Resolution:
Keywords:  simple  |
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Comment (by dustin):

 The idea here is to keep the amount of data in the `object_state` table
 from growing without bound.

 The only tricky bit is the need to retain backward compatibility.  It
 might be helpful to store some kind of state version number to make future
 changes easier.

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Ticket URL: <http://trac.buildbot.net/ticket/2656#comment:1>
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