Amazon EC2 grows 62% in 2 years

February 26, 2014

I estimated Amazon data center size about two years ago using a unique probing technique that I came up with. Since then, I have been tracking their growth (US East data center monthly, but less frequently for all data centers). Now is the time to give you all an update.

Physical server

I will not cover the technique again here, since you can refer to the original post. But I want to stress that this is measuring the number of physical server racks in their data centers, hence deducing the number of physical servers. There are other approaches, such as Netcraft that measures the web facing virtual servers. However, Netcraft only measures the number of virtual servers (and only a subset of it, those that are web facing), where a virtual server could be a tiny Micro instance, a very small slice of a physical server. If you want to know how big EC2 is physically, this is the definitive research.

The following figure shows the growth of the US East data center.

Number of server racks in EC2 US East data center

The growth in US East data center slowed down in late 2012 and 2013, but the growth has picked up quite a bit recently. It only added 1,362 racks between Mar. 12, 2012 and Dec. 29th, 2013, whereas, it has been adding on average 1,000 racks per year between 2007 and 2013. Then, all of a sudden, it adds 431 racks in the last month and half. However, other EC2 data centers have enjoyed tremendous growth in the two years period. The following table shows how many racks I can observe today, and at the end of last year vs. two years ago by each data center.

data center # of server racks on 3/12/2012 # of server racks on 12/29/2013 % growth 3/12/2012 to 12/29/2013 # of server racks on 2/18/2014 % growth 3/12/2012 to 2/18/2014 US East (Virginia) 5,030 6,382 26.9% 6,813 35.4% US West (Oregon) 41 619 1410% 904 2205% US West (N. California) 630 847 34.4% 950 50.8% EU West (Ireland) 814 1,340 64.6% 1,556 191.2% AP Northeast (Japan) 314 589 87.6% 719 229% AP Southeast (Singapore) 246 371 50.8% 432 75.6% SA East (Sao Paulo) 25 83 232% 122 488% Total 7,100 10,231 44.1% 11,496 61.9%

There are a few observations:

1. The overall growth rate shows no sign of slowing down. From Jan. 2007 to Mar. 2012, EC2 grows from almost 0 server to 7,100 racks of servers, roughly 1,420 racks per year. From Mar. 2012 to Feb. 2014, EC2 grows from 7,100 racks to 11,496 racks, which is 2,198 racks per year.

2. Most of the growth is not from the US East data center. The Oregon data center grows the most at 2205%, followed by Sao Paulo at 488%.

3. There is a huge spike within the last 1.5 months. The number of racks increased from 10,231 to 11,496, adding 1,265 racks of servers.

The overall growth in the last two years is 62%, which is quite impressive. However, others have estimated that AWS revenue have been growing at a faster rate of more than 50% per year. The discrepancy could be due to the fact that AWS revenue includes many other AWS services including some new ones they have introduced in recent years, and EC2 is just a smaller component of it.

Virtual server growth

Another way to look at EC2’s growth is to look at how many virtual servers are running. Since a customer is paying for a virtual server, looking at the virtual server trend is also a good predictor of EC2 revenue.

As part of our probing technique, we enumerate all virtual servers, regardless whether it hosts a web server or not. If a virtual server is running, the EC2 DNS server will have an entry translating its external IP address to its internal IP address. By counting the number of DNS entries, we arrive at an upper bound of the number of virtual servers running (it is an upper bound because when a virtual server is terminated, the DNS entry is not deleted right away).

The following figure shows the number of running virtual servers (active DNS entries) in the US East Data center in orange. AWS also publishes the number of IP addresses that are available periodically, and we have been tracking that over time. The blue points shows how many IP addresses that are available to assign to virtual servers. AWS has been constantly adding more IP address allocation ahead of the expected growth.

The green dots show the total available IP addresses across all data center. It is an upper bound on the maximum number of virtual servers EC2 can run. On Dec. 29th, 2013, our data shows there are up to 2.97 Million virtual machines that are active. You can put in an assumption of the average price AWS charges for an instance to roughly estimate EC2 revenue.

Density

From our data, we can also derive the density — the average number of virtual servers running on a physical server. On Mar. 12, 2012, there are 120 virtual servers running on each server rack. However, on Dec. 29th, 2013, this density has increased to 245 virtual servers per rack. Either the Micro instance is gaining popularity, or AWS has been doing a better job of consolidating their load to increase the profit margin.

Parting comment

I have not been blogging much in the last two years. You may be wondering what I have been doing. Well, I have been working on a startup, today we finally come out of stealth mode, and we are officially launching at the Launch Festival. It is an iPhone app, called Jamo, that brings dance games from Wii and Xbox to the iPhone. If this research has been helpful to you, please help me by downloading the App, and give us a 5* rating. You can read more about the App in a previous post.