Unexpected server error in Google App Engine

[Krishnan Sethuraman]

I have a PHP application running on Google App Engine that uses Google Cloud SQL.

Recently we have seen an an increase in our user count and since then we have been getting the following error.

This happens frequently but in random views. We are sure there is nothing wrong with the code. This error however disappears once the user refreshes the browser.

Can someone help us to understand why this is happening?

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[Yannick (Cloud Platform Support)]

Hello Krishnan, I assume you have not been seeing a corresponding increase of errors in Stackdriver Logging? If that's the case and errors are being generated by the platform before reaching your application, you should create an issue on an appropriate Issue Tracker where support will best be able to address your issue.