Does Appscale work on RaspberryPi3 with Ubuntu 16 Xenial yet?

[Jin Choi]

I tried to install Appscale on my host machine which is Ubuntu 16 Xenial with the bootstrap shell script.

But it failed with this message - 'Xenial is not supported'

So I installed on my ubuntu 14 precise virtual machine on Virtualbox and it succeeded this time.

Now, since I got what Appscale is capable of, I'd love to use it on RaspberryPi 3. I'm planning to buy one for Appscale.

But, Ubuntu For RaspberryPi indicates no Ubuntu 14 for RaspberryPi 3. So, Ubuntu 16 Xenial is the only option I can get with RaspberryPi 3.

Before I buy one, I wanted to make sure if Ubuntu 16 Server for RaspberryPi is compatible with Appscale.

I found this QnA on FAQ on Appscale Github wiki:

What Linux distribution does AppScale run on?
This shouldn't matter since AppScale tries to abstract away lower level details by running in virtual machines. AppScale runs on Ubuntu Precise and Debian Wheezy. It is simple to port to other Debian distributions.

I hope this is true. Thanks.

- Jin

[chris....@appscale.com]

Hi Jin,

AppScale should get support for Xenial soon. The biggest hurdle right now is that the AppController uses a Ruby library called soap4r, which hasn't been ported to Ruby 2.3.

In the meantime, it would probably be quicker to port AppScale to Debian Jessie since there is a version of soap4r that runs on Ruby 2.1.

You may have already done this, but I would suggest giving your test VM only 1GB of memory like the Raspberry Pi 3 has. While it is possible to run Cassandra with only 1GB of memory, it's generally recommended to have at least 4GB. Others have run AppScale on a Raspberry Pi before, but you may want to make sure the performance with that hardware meets your expectations before buying one with the intent to run AppScale on it.

Anyway, it sounds like an interesting project! We'd love to hear how it goes.

-Chris

[Jin Choi]

Hi Chris :)

Thank you so much for your help. I just wanted any OS for RasPi3 with Appscale. Debian Jessie is a perfect alternative for me.

And thanks for your kindly suggestions for performance testing.

Speaking of which, do you think if an app is a too huge for one RasPi3 handling requests within reasonable time, configuring a cluster of multiple RasPi3's will solve the low performance problem?

Or, is it not like something that I could overcome with a bunch of 1GB RAM's and I just need RasPi6 or something? If there is no a known fact regarding this, just a thought will be also appreciated.

- Jin

[chris....@appscale.com]

Adding more machines with the same specs to a cluster will improve the throughput of the deployment, but it may not always improve the latency. It depends on where the performance bottleneck for your application is. For example, if your bottleneck is CPU and a certain request takes 1 second to process, adding machines will not make that request take less than 1 second. It will, however, allow you to process more simultaneous requests per second.

From a memory standpoint, putting your 'database' roles on a separate machine than the other roles will definitely help. 1GB should be plenty of memory to run most App Engine applications (our default max_memory is set to 400MB), so your main constraint will probably be Cassandra on your database nodes.

Here's an example layout you could test with VMs:

ips_layout:
  master: <machine-1>
  appengine: <machine-1>
  database: <machine-2>
  zookeeper: <machine-1>