What does Piriform Defraggler's "Optimize" option for SSD do?

Question

I regularly used Piriform's Defraggler to defrag my hdd. Switching to SSD, I thought it was no more necessary, as SSDs do not require defrag.

I used it to make a benchmark, and the program proposed to run a SSD Optimization on my SSD.

Can you explain in what does this consist?

Solution

At best it can TRIM the disk. Effectively running through any unallocated space and telling the drive what areas are specifically unallocated and can be reclaimed for use. The blocks that are reclaimed can be pre-emptively erased before they are required for writing and so potentially improve performance.

Trim was introduced soon after SSDs were introduced. Because low-level operation of SSDs differs significantly from hard drives, the typical way in which operating systems handle operations like deletes and formats resulted in unanticipated progressive performance degradation of write operations on SSDs. Trimming enables the SSD to more efficiently handle garbage collection, which would otherwise slow future write operations to the involved blocks

If the blocks are not erased beforehand then you may notice a drop in write speed as they must be erased before being written.

This should already be being done on a regular basis by your operating system, but there should be little harm in issuing a TRIM slightly more regularly. There's little reason to do it more often either than really necessary though, unless you regularly fill up and delete a lot of data on your disk.

Actual defragmentation though is pretty unnecessary and potentially harmful to the lifetime of the drive as it will be actively copying and writing to the disk and wasting cell write cycles.

Comments

[Moab]

Which OS are you running?

[Gantendo]

Ahskually hanselman.com/blog/… (but yeah this just interesting background info, no Windows user should defragment their SSD, Windows does it automagically).

[Mokubai]

@Gantendo that sounds far less like conventional defragmentation (in the hard drive sense) and more a reorganisation and restructuring of the filesystem metadata. More of a garbage cleanup to fix volume snapshots than a rearranging of the entire data structure on the disk surface. It also sounds like if you don't have system restore enabled then it won't "defrag" at all and reverts to mostly TRIM. I think by default Windows 10 has that disabled. There's a lot more nuance than "Ahskually".

[Gantendo]

Yeah, like I wrote, its just a fun bit of background info. I figured you'd be interested. I was.

[Mokubai]

Oh, I only saw the first part of the comment but yes it was interesting background. It does seem to boil down to "don't use HDD defraggers because the built in one knows what it is doing and the others are just blindly doing an old style defrag". It was an interesting read, thank you.