The Perils of Success – “Quota Exceeded”
February 24, 2011
Yesterday, the Silver Smalltalk site at http://www.silversmalltalk.com was unavailable for much of the day due to a “Quota Exceeded” error.
The site is hosted on Google’s App Engine servers which are capable of supporting extremely large applications. There are adjustable quota settings for several types of resource usage which are billed after a (quite generous) free quota is exceeded within a 24-hour period.
Above, I have posted an image of the traffic patterns over the past two days.
Until very recently, traffic was mostly negligible. Then, early yesterday, there were over 2000 visits in the space of a few hours.
Currently, I am using the ExtJs libraries and they are greater than 500kb when all the various images, *.css, and *.js files are included. (QuickSilver compiler itself is about 50kb non-minified).
So what happened was that 2000(+) visits times 500(+)kb exceeded the bandwidth-out quota of 1GB per 24 hours. And the network was unavailable for much of yesterday.
What I have done to address this particular problem is to load the ExtJs libraries from the CacheFly content delivery network instead of from Google.
This means that I will now be able to support thousands of visits to the site per day before exceeding the current quotas.
Hopefully, traffic will continue to increase as the benefits of developing in an online Smalltalk environment become more widely known.
And, inevitably, there will be consumption of other resources that approach their quotas.
In that case, the solution is for me to begin paying Google for the increased usage…
But, for that to happen, the site must start generating a predictable revenue stream….
Which will only happen once it becomes more popular…….
That is where things stand at the moment.