On Monday, the Grouper UI was, at times, unusably slow. This, understandably, was a great inconvenience to several people. For that, I apologise. It was unforseen but we now understand the reasons and have formulated a plan of action.
Firstly, the reason – why did this happen? Well, the eagle-eyed amongst you may have spotted that Monday was the first day of teaching for the majority of our students. OK, I hear you say, but what does that have to do with Grouper? Well, it’s actually down to the phenomenal popularity of the Newcastle University mobile app. The way the app is currently architected, there is a web service call to the Grouper API every time a student logs in to the app or they refresh their news feed.
Chart showing a large spike in logins to the mobile app at start of term
The chart above shows the spike on Monday, when new students downloaded the app for the first time and returning students logged in to see their timetables. The resulting spike in calls to the Grouper API were too much for the poor little server to handle, with the database process maxing out the CPU.
So, what are we doing about it? Well, we’re not just going to stand here and do nothing but apologise. Our approach is three-pronged (rather like a fancy dessert fork):
- We’re going to add more CPU to our Grouper server.
- We’re working with Mike, Mike, Andy and Marc to redesign the data architecture behind the app, using purpose-built RESTful web services from IDFS and removing Grouper from the equation.
- We’re continuing with our Grouper upgrade plans.