Taming the public cloud beast: Your monthly bill
By Yatin Kulkarni
Yatin is a technology evangelist and a hands on solutions architect with over 20 years of global and cross-cultural experience in various industry verticals such as Publishing, e-Commerce, Digital Marketing, Map Data Management, Petrochemicals, Health Sciences, and Food Retail. He is currently focused on re-architecting traditional enterprise applications to leverage the latest IaaS and PaaS offerings from the leading public cloud providers. He maintains a blog at http://gnosko.in.
Beyond a doubt the public clouds have been a godsend to practically all the startups out there today. Plus the ongoing price wars between the major players: Amazon, Microsoft, Google, IBM, has meant that the price per unit of compute/storage/network capacity has been on the decline. Even adoption amongst the traditional large enterprises is on the increase with success stories being written on the hour every hour. So then how does one explain articles such as the one below?
And this is not an odd one out case. and other similar articles are available albeit they don’t exactly show up on the first page of most search queries pertaining to cloud pricing/costs thanks to the excellent SEO efforts by all the big providers.
The bottom line: Just like dining out every day at an unlimited buffet leads to obesity ad-hoc usage of cloud computing resources leads to a bloated bill that can take many a startup by surprise. Is the answer then to simply jump ship and switch over to a private cloud or worse yet a traditional infrastructure model? All of the players in the private cloud space are trying hard to convince you to do so. Here is an excellent white paper from Eucalyptus to help you take the leap. Maybe not just yet if some of the strategies outlined below are adopted appropriately.
Utilise compute resources for the shortest possible time: Throughout the history of the World Wide Web the one golden rule followed religiously has been: Be always available lest your loyal consumer ditches you the instant your site is down. Given that public clouds rely on sharing the same physical resources across multiple customers it should come as no surprise that the cheapest pricing plan available for the longest time was the one wherein you spun up reserved instances with a guaranteed up time of 99.995% or better. Not only do you end up paying an upfront charge but also the costs can spiral exponentially as you keep adding nodes. To add to your woes as the application and data complexity increases along with the upsurge in customers you start spinning up the more expensive high end instances.
Invest instead in re-architecting your applications to utilise micro instances by adopting a micro services based approach or better still invest in building up your in house DevOps skills to leverage the on-demand and spot pricing plans. The latest PaaS offerings from Amazon such as AWS Lambda, and BlueMix from IBM provide a host of ready to use micro services that can be leveraged on a as needed basis. To add to that the newest auto-scaling offerings from some of the providers also allow you to spin up container based compute instances instead of entire VMs.
Have a crystal clear strategy for processing raw usage data and/or archive it as quickly as you can: Success in boosting site traffic which invariable leads to more business brings with it a deluge of raw usage data that in turn holds the secrets to the next chapter of your growth. Hence it is very tempting to hold on to as much usage data as you can. Plus there may not be a clean separation between transactional and raw usage data. All the cloud providers leverage this aspect of the growth phase of any startup to drive up your monthly spend. Hence it is critical to watch your storage needs very closely and adapt to increasing raw usage data very quickly.
To start with ensure that you can clearly demarcate between transactional data and all other data generated until the time the transaction is actually completed. Also make sure you can easily sift between anonymous usage data and that associated with a known logged in customer. Store all usage data using object based storage services such as AWS S3 limiting each bucket to a relatively short time duration say five minutes and employ data aggregation to reduce data volume by aggregating to a longer time duration say one hour. The key here is not to try and convert the data to a full-fledged data warehouse/mart schema at this stage. Once the raw data has been thus processed it should be archived on a daily basis using solutions such as AWS Glacier. If you don’t have a strategy to further utilise the semi-processed usage data to populate a data warehouse then archive that as well say on a weekly or monthly basis.
Reduce network traffic to the compute instances and between different availability zones: This is probably the most easily overlooked aspect of your monthly bill. Most of the savvy startups will quickly utilise CDN for static content and script caching thereby reducing network traffic to the compute instances hosting the web applications but as your overall cloud infrastructure grows and you start spanning availability zones for ensuring high availability and disaster recovery the corresponding increase in network traffic across availability zones will start adding up quickly. Luckily your startup will have to be wildly successful before this component of the monthly bill will require too much attention and by that time you will be able to afford the real high end talent required to optimise the architecture further.
The kind of monthly spend on public clouds as described in the article referenced at the start of the article represents a dream come true to most of the startups just starting out of the gate but it is always a good idea to start adopting the right strategies and architectures to manage your monthly spend from the very beginning when even a thousand bucks out of your pocket can seem like a million. Furthermore the right architecture will help you eventually transition to a hybrid cloud model at the right time in the future with the least amount of effort and risk.