Too many simultaneous invocations: Spreadsheets

[Yidan Wang]

I wrote a Chrome extension which calls a Google App Script endpoint. The Google App Script then checks a spreadsheet and passes some data back to the Chrome extension. However, when a lot of users use the Chrome extension at the same time, this error shows up - "Too many simultaneous invocations: Spreadsheets at functionName(Code:11) at doGet(Code:5)"   

Apparently there is a limit on simultaneous executions of Google App Script functions. Is there a way to avoid that error?  

[testing apids]

maybe you can try to pause executions until the simultaneous executions are finished. Still trying to figure out the best way for this. Any ideas?