A Brief 10-Point Guide to AWS Lambda

When I'm learning new about new technologies, one of the first things, I'll do is write a numbered list 1-10 and then fill that numbered list in with points about that particular technology. I realised that these lists might be useful to others so I'm going to start posting them. This week I looked AWS Lambda.

1. AWS Lambda lets you run an application without rigging or managing servers. It is an event-driven computing platform. The code is executed in Lambda upon configured event trigger.
2. AWS Lambda uses a Function as a Service (FaaS) model of cloud computing.
3. With AWS Lambda you don't need an application that is running 24/7, as a consequence, you only pay for the time your functions were executing which can lead to a significant cost-reduction against traditional server-based architectures.
4. Due to the nature of AWS Lambda's FaaS model of cloud computing, development times for applications can be greatly increased, because the problems of managing an application stack within a server-based context are eliminated.
5. Planning and management of resources are efforts, which are nearly completely removed with AWS Lambda, because of its auto-scaling when more computing power is needed it will scale up the resources seamlessly, and conversely, when fewer resources are required it will scale down seamlessly too.
6. A greater proportion of developer time is available for working on the problems and challenges of the business logic with AWS Lambda.
7. One of the drawbacks of using AWS Lambda is that is is not necessarily faster than traditional architectures, this is because when a new instance of a function is invoked it needs to start up the process with the code to be executed. This start up time is not present in traditional server-based architectures the process or processes are running all the time.
8. A further drawback of using AWS Lambda is the issue of concurrent executions of functions. The default account limit for concurrent execution of functions is 1000, although depending on region this can go up to 3000, but this has to be specifically requested. Few applications will have to worry about this problem however. One additional thing of note about concurrent executions is that AWS Lambda does allow you to specifically limit the concurrent executions of specific functions.
9. The current maximum execution time for a AWS Lambda function is 15 minutes, which can be problem if the function is running a task which will take longer. Although this would be a sign that the function should be decomposed where possible.
10. A further drawback AWS Lambda is that individual functions are somewhat constrained in there access to computational resources. For example the current RAM limit of an AWS Lambda function is 3GB.