Reducing AWS EC2 Instance and RDS - Is 'low' Network Performance acceptable?

Question

I launched my site on AWS a few weeks ago. I have a m3.medium EC2 instance and a db.m3.medium RDS instance (MySQL database).

I've looked at the monitoring for each and this is the average usage for each:

• RDS 6% CPU Utilization
• EC2 10% CPU Utilization

Clearly my site is hardly consuming any of the available resources.

I want to reduce the instance size without impacting on the quality of my website's responsiveness. However, the only thing that is putting me off is that each of the smaller instances state Network Performance: LOW.

Has anyone else had any experience with the smaller instances? db.t2 for RDS and t2.medium, t2.small for EC2?

Is the network performance terrible? Is there another way to reduce costs?

Answer 1

This question is difficult to answer as you'll need to determine "acceptable".

The "Low" rating will almost certainly result in slower transfer rates, and depending on the region and the time of day/year you may find contention on the host where your instance lives.

"Low" network may also get the least priority which may lead to unacceptable performance during times of heavy congestion in the network.

In practice, you'll probably find stepping down to be acceptable for cases like when you're not hit with a lot of traffic, and some minor blips are acceptable.

You can employ caching, load balancing and other methods to increase your performance which may mitigate some of the downsides of a lower powered machine.

You can also (reasonably) quickly switch the instance type back up as required.

Why not setup a replica stack and do some performance testing?