The hidden cost of cloud computing

At the company, Aputek , we work with big data and due to various circumstances we distribute all our infrastructure in various data centers, this is due to regulatory issues, costs, performance, in short... The thing is that we work with 8 different cloud providers and reviewing our statistics on productivity and costs that we have been incurring, I began to do something that I had never tried: evaluate the economic efficiency based on performance and performance of our suppliers. It was not an easy task because our compute (instances) units are different in each provider and I needed to generate the metrics with what we already have. I made an exception to this with Vultr (the 9th one) where I raised a VM to add it to my studio.

This article can be very dense but I am going to focus only on the key results for my case and towards the end I will share the tables and formulas that I developed to calculate everything that I expose.

I focused on the efficiency of the CPU based on two cores, as well as the throughput of the disks and even the network drives. I discarded the memory factor because although it impacts many operations, there is a great variety of options (flavors) and it is associated with the requirements of the applications that are going to be executed. Another no less important factor is only taking as a model, the virtual machines or bare metal (yes there are 2) of standard configuration, without major complexities, considering that yes with SSD disks.

The machines that I have used, as I mentioned, are part of many of our data clusters in various data centers from various providers, some do #scraping tasks, #massive #dataanalytics , #realtimeanalytics , #machinelearning , IOT processing and clinical equipment adquisition or simply support #microservices from our solutions.

I must add that this article is not intended to select the best cloud provider, but simply to obtain a metric to make better decisions based on the provider we work with. There is also an important factor: acquiring a virtual machine (or bare metal) does not solve much for us, it can be part of our architecture to develop a service, but there are many additional associated costs: from the type of CPU, the size, and the speed of the disk. , incoming and outgoing traffic, security images, ips, etc. Each one offers various advantages in this regard, to cite a small example: Digital Ocean offers a VM with 2 CPU / 4 GB RAM with 80 GB of disk and 4 TB of data transfer all USD 24.00, meanwhile IBM offers the same machine with 25 GB of disk and only 250 GB of transfer for USD 58.52. In summary: there are many components that we must evaluate to support our infrastructure, but in many cases the center will be the VM (unless you do everything serverless).

Having made all the clarifications of the case, I will concentrate on the subject of my study. To measure the performance of the CPU I used SYSBENCH considering only 2 cores and for the storage (disks and network drives) FIO the creation of a 4 GB file. I carried out the process 5 times in each scenario, I showed the best data obtained in the table and graphs. I added two bare metal (of several we have) to all of this to help further focus the value I wanted to find.

The table below shows all the information obtained and tabulated, starting from this I began to highlight the most relevant data and develop my factor.

Compute Benchmarks

First interesting fact: the highest CPU performance with the lowest cost on the market on this list is from Oracle with its #ARM instances, and to top it off they offer you 8 CPUs and 24 GB of #ARM RAM for whatever you want at no cost per month forever (at least until it is no longer the case). We use it in #scraping and it is really delicious.

CPU Benchmarks

In terms of storage performance (disks) we have that the big winners are Hetzner and Vultr, the difference in reading and writing is more than 50 times between some providers. Can you imagine running a database, storing images for analytics or any task that requires disk speed? At this point, many vendor "architects" will tell you how to do it in the most efficient way at a cost that is surely more prohibitive by adding a series of services that they offer. On this point I want to tell a little anecdote: a couple of years ago we went to the offices of one of our cloud providers to get "advice" on how to improve what we already had, particularly our scraping component that requires hundreds of robots to launch in a synchronized way taking advantage of each request and therefore all the information we obtain must be processed and stored in a database, in this case #postgresql , it is true that we used redis as an intermediate solution but at a certain moment we had to save 8270 data per second. The #postgresql solution offered by this provider only allowed me 105 writes per second and also had to consider the number of CPUs, storage, etc. which made the cost of the service 10 times more than a VM. My solution was: we set up our #postgresql cluster on the machines and saved our data without the restrictions that the provider's solution had (which, by the way, they didn't know they had).

Disk Throughput

After many calculations, taking averages of offered instances, factoring CPU cost, relating it to storage, etc, etc. I got what I wanted: a table showing me the providers with the best CPU, Disk and Price performance: Value Factor by Compute Unit. The yellow line is careful, it indicates how much the product (the instance, VM) is worth in relation to what it offers, where we have Hetzner, Vultr and Oracle ARM very good options.

Value Factor by Compute Unit

When we work with data clusters, #Kubernetes for example, we will always need shared #network drives for all the data and there, depending on what we pay, we can store the data in common, images, databases etc Remember that if this test has been done with standard configuration without adjusting the #IOPS , if one does that, the cost can rise X times and it is something that we must consider. Here Oracle stands out, but in the case of Hetzner, since they do not offer a redundant storage solution in their infrastructure, we had to make one with a cluster of nodes, which obviously triggers performance because it is something ad hoc.

Network Storage Benchmarks

I hope this study helps you make better decisions when dealing with your cloud architecture and to avoid controversy I am sharing the sources I recorded and the calculations (subject to validation) I made for the Value Factor by Compute Unit. I will be attentive to your comments.

Sources:

Raw Evidence:

https://docs.google.com/document/d/1eSi-RsP7oyEKhGgseZCXj68ardzU6vWX-_QW-8Gsamw/edit?usp=sharing

Calculations:

https://docs.google.com/spreadsheets/d/1jksk35vqlbEdnEtr6b5BZYISz9ovjmw1ynkMXKogS5I/edit?usp=sharing