The purpose of this page is to try to imagine what the amount of disks needed to store the volume of emails sent in France might be.

Number of email storage drives
Photo by benjamin lehman on Usplash

In 2020, the SNCD indicates that the volume of French emails is 143.65 Billion, for our calculations we will round to 144 Billion.

This is a very difficult (impossible) calculation to imagine/represent because there are surely as many ways to store emails as there are providers who store them, so there will only be hypotheses here that are just asking to be challenged, the goal being to just have an idea to picture things.

It’s conceivable that recent emails are stored on fast (SSD?) and small capacity storage (more common than spinning disk) because we’ll potentially need to check them more frequently than old emails which could be stored on slower, larger capacity drives. Without counting the disks of the Internet users who download a copy of the mails on one or several terminals (pc, tablet, mobile…) that we are not going to take into account here.

In my hypothetical, recent emails from the last 6 months are on fast SSD storage. That is 144 Billion emails divided by 2 and therefore 72 Billion emails for 6 months.

We assume here that an email is about 90kb.
72Bn emails represent 6480TB (72Bn x 90kb)

Imagine that there is replication on 3 1TB disks (it could be 2 or more, but had to make a choice for the calculation)
6480 / 1 * 3 = 19440 1TB disks

These emails are of course saved. (well I hope 🙂 )
We can imagine doubling this volumetry (I’m simplifying because between full, incremental backups… it’s hard to estimate)

To get an idea, I assume that the backups are 2 times the total weight, which makes a size of:

19440 + (19440 x 2 ) = 58320TB or 58320 1TB disks

Now let’s move on to the last 6 months of the year and thus the remaining 6840TB.

I’m also going with a 3-drive 6TB SATA replication
6480 / 6 * 3 = 3240 6TB drives
We’re applying the same backup logic for the volume:
3240 + (3240 x 2) = 9720 6TB drives

So we arrive at a total of 68040 disks and we are surely still far from the count with the copy of messages on the terminals.