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Quick update on Site Monitor and Google App Engine D-Day

I’ve made a few changes to the way the monitor works in the hope that it will reduce the load on the app and thus the cost based on the new App Engine pricing. There are three implications you should be aware of if you use the monitor.

1) ‘Up’ emails are not sent anymore.
You’ll just have to trust the site is being checked, without the email confirmation.

2) Checking will be 24 times per day, roughly one hour apart
I’ve changed the way the monitoring queue works, so that the sites will be not be dequeued concurrently, and so checked more slowly. However they should all get checked every hour, approximately one hour apart. Failed sites get checked 2 further times to make sure they’re really down, these rechecks will happen almost straight away.

3) If your site is down for 96 consecutive checks (about 4 days) it will no longer be checked.
This is to stop sending endless emails for weeks when a site is taken offline.

Hopefully these changes will keep the monitor running for free from here on out.

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Google App Engine billing changes and my website monitoring service

A long long time ago I wrote a simple little monitoring service on Google App Engine. It’s been happily ticking over for the last couple of years but with the recent changes to Google’s App Engine pricing, I’m going to have to make some changes.

This is a blog post for those who do use the service (there’s over 100 of you!) and may care about whether it is still monitoring your site. I sent this email to you all (sorry for the spam!) and will make any further updates on this site to save your inbox tears.

Hi, All

I’m Ashley, I made the website monitoring service you signed up for
here: – if you no longer use it, or
don’t care, please delete this email – I won’t be sending any more.

If you’re still with us so far, firstly sorry to spam all of you, but
there’s been some important changes by Google in the way they price
the App Engine platform, and apps like this monitor service, are not
free any more.

I’ll do my best to do a quick rewrite of the monitor in a way that can
keep the running costs at zero, but if I can’t, I’m going to have to
shut it down. If that does happen, I’ll gladly open source the code,
so that you can all run your own version of it, on your own app engine

As promised I won’t email any of you about this again, I know how
annoying emails like this are. If you use and care about the service
working, subscribe at for updates on the
future of the monitor, and the code if/when it is open-sourced.

Any questions, please just ask me.

Kind regards,

So either there’ll be an update about what the new service does and does not do, or there’ll be some code so you can run it yourself. D-Day is Nov 7.

I will just say, I’m still a big fan of App Engine, despite the changes – it’ll remain my platform of choice for future projects until something better comes along.