If you get a transaction collisions on objects you need to Shard the object. Look at this talk video http://sites.google.com/site/io/building-scalable-web-applications-with-google-app-engine
2009/1/9 Ryan W <[email protected]>: > > I was noticing what appeared to be some entity saves/puts being missed > or ignored by the datastore. I suspected it was due to contention of > many updates for the same entity coming in to fast. So, I put it in a > transaction (incrementing a view count when a page/entity is viewed). > > As soon as I put it in a transaction, I began getting lots of these: > > "Transaction collision for entity group with key > datastore_types.Key.from_path" > > I couldn't find much for this error, but it sounds like these should > be avoided. Is it accurate to say these should be avoided, or are > they pretty harmless? Is it still saving though? > > What are some strategies for reducing contention? Storing hits/counts > in memcache and periodically persisting to the datastore? > > This model is of type searchablemodel, so perhaps that's not helping > things? > > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Google App Engine" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en -~----------~----~----~----~------~----~------~--~---
