How to Calculate Over-Provisioning on Your PC SSD

One of the biggest problems that many SSD models have today is that, curiously, the manufacturer has not endowed it with the so-called over-provisioning, also known as over -provisioning . This technique that we already talked about is tremendously useful and if your SSD does not have it, you may want to do it, for which you must know what space you should reserve for it, but how to calculate it?

None of us want their SSD to fail, but we also want the maximum available capacity to store all of our data. Sometimes this is not possible and in fact it should not be possible due to the so-called Over-provisioning, which is increasingly necessary. If your SSD doesn’t include it … You may want to do it yourself.

Calculate Over-Provisioning

Over-Provisioning, not fit for all SSDs?

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Unfortunately, this technique requires the manufacturer’s software to allow this use, at least with Windows already installed. Another option is that when installing Windows, let’s create a partition that doesn’t use the full capacity of the drive. Either Windows itself or the SSD driver will automatically interpret and use that empty and unused space, as well as unformatted space to make the call about dynamic provisioning.

This will increase the durability of the SSD, as well as its speed, but will decrease the total capacity of the same, for this reason it is important to take into account what percentage values we are going to use in order to maximize the two named parameters and lose the minimum available capacity.

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For this reason, manufacturers have a kind of unwritten consensus where they stipulate a percentage value range for Over-provisioning: from 7% to 28% and where the average value is 14% . It must be added that we must know what is the greatest use that we give to the SSD, that is, we must have a very approximate idea about the readings and the writes, since this way we must vary the value.

A very simple mathematical operation

Over-provisioning

As in everything, there has to be an intermediate starting point for the vast majority of SSDs, although then each one applies the percentage that it stipulates according to its use. To calculate Over-Provisioning it is necessary to know the physical capacity of the SSD and the real accessible capacity that we have.

Knowing these two simple data we will only have to subtract the physical capacity minus the accessible capacity and divide that number by the accessible capacity. The result will finally be multiplied by 100 and that will be the percentage of Over-Provisioning that we should have for normal use.

In contrast, if we use many random readings, manufacturers recommend the lowest possible OP value (7% ). If instead we are one of those with many more deeds, the value will be the maximum recommended ( 28% ).

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14% is the midpoint between the two, so it is very important to analyze how many readings and writes we make in a daily use of our SSD in order to fine-tune as much as possible. Logically before doing this, we must make sure that our SSD does not already have an OP in itself, since many manufacturers do include it as standard, where in that case obviously we will not have to do anything.

Keep in mind that the space allocated as OP is invisible to the operating system and is therefore not accessible to the user, as it is strictly for use by the SSD driver.