Anant Patil fe119a89f6 Convergence: Stack concurrent update ... The stack update API needs to know the expected traversal ID of the stack (each update is associated with a unique traversal ID) it is updating. When two updates are triggered simultaneously - for example, in a case where two resources at same level try to rollback the stack when they fail at same time - then the updates need to give the traversal ID they intend to update. If it happens that the resource A triggers the rollback immediately after the rollback of A has started, but before A has persisted in DB, then the system is in erroneous state. Steps to describe the problem: 1. Resource A and B of a Stack S fail. 2. Resource A loads the stack. 3. Resource B loads the stack. 4. Resource A triggers rollback - it takes the previous template as current template, updates the DB. 5. Resource B now again triggers the rollback. It is not aware of update triggered by resource A. If the updates triggered by A and B give the stack traversal they expect to be updated, then update from resource B will fail, since the expected traversal ID will not be found in DB as a result of resource A already updating it. Change-Id: I13b2f5afe8cadf9a2d9ab4139a14718a5481dec4		2015-09-04 12:00:37 +05:30
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sqlalchemy	Convergence: Stack concurrent update	2015-09-04 12:00:37 +05:30
__init__.py	Do not initialize anything during import phase	2013-04-24 10:03:06 -07:00
api.py	Convergence: Stack concurrent update	2015-09-04 12:00:37 +05:30
utils.py	Support for encrypt/decrypt parameters in heat-manage	2015-06-05 12:06:59 -05:00