

Ask HN: AWS & EC2 how to calculate for raising finance? - chris_dcosta

I'm looking for three things really, and I know it's a bit of a "how long is a piece of string" question:<p>1) What is your experience of sizing and selecting and costing in advance of raising money (mainly AWS and EC2 - but any equivalent experience also welcome)<p>2) after having raised the funds how accurate was your prediction?<p>3) if you were raising again, what would you recommend doing instead?<p>Lastly, please speak about <i>your experience</i> as in, the number of users and concurrency you needed, on average how much space they required for each user, what db you were using.<p>I hope this is not asking too much!
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jtchang
This is standard capacity planning which I use to do as an architect in a
previous life.

It really comes down to your business model and assumptions. You tell me that
your model says you will have 1000 users in Month 1, ramping up 100k users /
month till month 12? I will then use that to plan everything else.

For one project we had a requirement of 500 concurrent users constantly using
the system. Disk space was not as big a concern as memory/ram. To support
these 500 users we needed about 6 large instances. Yes this is a lot of
hardware for a very small # of connections which speaks to how intensive the
app was.

If you need help be glad to take a look at your specific case.

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thspimpolds
As jtchang said, yes it comes down to planning.

Ask the founders (or if you are one you should know this) what your daily
active uniques are. Also ask what language you are getting code in. Java needs
more headroom than c++ for instance.

Then plan +40% capacity of whatever they tell you.

Always use an Aws autoscaling group to shave costs, but price as if you had
always on on demand pricing.

Don't forget to think about supporting infrastructure. Do you need memcached?
If you do how much? Will you run your own or use elasticache?

It all comes down to architecting your system on a whiteboard with needed
resources (CPU, ram, etc) and then take that and apply it to the the instance
type matrix and see where it fits

My experience is based on three startups each with 2n or greater redundancy
each handling at least 500 req/s into the frontend

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davestheraves
I'm going though this process now as well. Any pointers, even not specifics
would be great!

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spuiszis
I am also interested as well

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cloudsteam
I too am interested in this

