Replacing Drive with SSD

Paul Kraus paul at
Thu Sep 10 17:42:40 UTC 2015

On Sep 10, 2015, at 11:00, Brandon J. Wandersee <brandon.wandersee at> wrote:

> Leaving blocks unpartitioned doesn't mean those blocks won't be written
> to; it just ensures that a certain amount of space (and so a certain
> number of blocks/cells) must always be free, forcing writes to be spread
> across different physical portions of the disk in a relatively even
> manner. It's my understanding that this over-provisioning isn't
> exactly necessary in most SSDs nowadays. It just serves as a stronger
> guarantee than entrusting everything to a drive's firmware.

Each SSD model has some amount of over provisioning built in. The more expensive, Enterprise grade SSDs have more (in many cases much more) than the cheaper consumer units. So based on the performance you need and the SSD you have, it is still prudent to manually over provision with unpartitioned space.

Note that some vendors will tell you about their over provisioning and others don’t.

Paul Kraus
paul at

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