Earlier this year, this issue occurred because of a bug in appengine's memory estimation: http://stackoverflow.com/questions/17259928/randomly-121-error-on-google-app-engine . There are several other mentions of this problem on stackoverflow ( http://stackoverflow.com/search?q=121+appengine), on google code and google groups. In these posts I have not found any response from Google indicating what this error means or how it can be prevented. It happens both in Java and Python applications.
This blog posting<http://fromthepantothefire.com/2013/01/16/google-app-engine-error-121/>indicates that the problem would be minimized by having a paid subscription. But my app runs under a paid subscription, and the 121 error still occurred. It caused a lot of stress for my customer, and for myself. For other reasons I was already looking at alternatives to appengine, and the "121 issue" is even more reason to look for better cloud options. Since my app was written for appengine, Appscale <https://github.com/AppScale/appscale>might be viable. It runs on Amazon EC2, but I have no data on its reliability compared to Google appengine. Heroku is also interesting, but I would have to / want to rewrite my application. Even Microsoft Azure looks good, since it allows you to use node.js which is far better than the limited Java (or Python) implementation on appengine. -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/google-appengine. For more options, visit https://groups.google.com/groups/opt_out.
