To look at if we should defrag an SSD drive, lets answer two questions first;
- Why do you defrag a disk drive?
- How does SSD work?
Why do you defrag a standard spinning disk?
You defrag to limit the amount of “seek time” that the drive head needs to get to the portion of the platter to start reading the disk. When files are fragmented, the drive heads need to waste this time for each fragment of the file that it needs to read. So we defrag a drive to limit the number of jumps and associated wait times that are needed to read an entire file.
How does SSD (Solid State Drives)work?
Solid State Drives (SSD) work in a completely different method then the standard spinning disk. First off on spinning disks, they try to write the data at the first open area to limit loss of time due to moving the head or platters. On an SSD drive, there are no spinning disk. But there is another issue, any memory location only has a limited number of reads/writes. Using one location of the drive will cause that memory to wear out and fail. This isn’t noticed as an issue because all SSD drives have a controller using algorithms to spread the load out across all the memory. This means that the SSD drive purposely fragments and moves data around to limit overuse of a single section.
So that leaves us with the last question, what happens when you defrag an SSD drive?
Well the defrag application will try to move the file to a specific location, the SSD controller will move it to where it feels is the least used location. This is kept up till either the user shuts down the application, or the drive burns out from rewriting the data over and over again. Defragging an SSD is a great way to significantly reduce the life of an SSD drive.
Jason Howe, PEI
