[r00fus]

I haven't defragged a disk in almost a decade. When is defragging an SSD ever a good thing?

I only have spinning rust in my (older) NAS or as backup drives.

[petecooper]

I don't defragment SSDs at all. I should've made that clear in my comment.

I have a multi-HDD system running to 6TB of storage, I can't run to the £ of an all-SSD system at the moment, but that's on the cards for the future, so it's spinning rust for me, for now.

[tinus_hn]

Probably often but there is no way to tell really because the controller has a mind of its own and they are all different.

[forapurpose]

> Probably often

Defragging an SSD is often a good thing? Why? It would seem to greatly increase wear for no benefit.

[akvadrako]

If your fragments are really small like 16kb then you could see a significant performance improvement, due to better predictive loading and packet overhead. This is clear from SSD benchmarks.

But I don’t see how this would ever realistically happen.

[forapurpose]

What about the massive effect on wear?

[tinus_hn]

You don’t know if there is wear. The controller is a separate computer. It may be clever and just remap blocks if you copy or move them around. It could be that defragmentation allows the system to work in a way that is better for the controller or allows that controller to place the blocks in a better way.