Should You Defrag A Solid State Drive?
Hi there! One of the more common questions I get from friends is whether you should defrag a solid state drive. Well, research has clearly indicated that defragging SSDs is an extremely BAD idea. There are several reasons why – and we’ll explore these in this article.
1. Defragmentation in Hard Disk Drives
Traditionally, if you’re a hard drive user, you’ll know that they have moving parts. The hard drive heads will be slowed down if they need to move from place to place to seek data.
So what hard drives defragmentation programs do is to move the data into one area so that the hard drive finds it easier to seek data. In fact, mechanical drives typically have long seek times of approximately 15ms.
Every time a file is fragmented (with data distributed across different parts of the disk), you lose 15ms finding the next data block. This all adds up to a lot of delay and hence poor drive performance.
2. Why You Don’t Want to Defragment SSDs
Now, in solid state drives, the location of data is actually irrelevant. You don’t have moving parts in a SSD trying to seek data in one location and the next – the reading / writing of data is all done via NAND flash memory.
SSDs typically come in two flavors of NAND memory – Single-Level-Cell (SLC) and Multi-Level Cell (MLC) .
SLCs is more suited to enterprise usage while MLCs are cheaper and more for consumers.
In MLCs, by design, the drive manufacturer will try to write to many cells as possible and not concentrate data storage on a single cell. This is to preserve P/E cycles for each cell in the drive.
In this sense, SSDs already store information in a “fragmented” way and there is no need to defrag them at all. And even though the information is “fragmented” in a SSD, it still performs MUCH faster than a hard disk drive.
What’s also important is that SSDs have a limited number of write (program-erase, or P/E) cycles (i.e. you can write a maximum number of times to a drive before it dies).
If you defrag a solid state drive, you will use up those write cycles and shorten the lifespan of your disk. Now, we’re not saying the the maximum number of writes in SSDs are so small they will die off in one or two years (typically the write cycles will last you maybe 20 years) – however, it’s still good to do what you can to make your drive more durable.
3. Tips About Defragmentation
Now that you understand we don’t need to defrag SSDs, you should definitely turn it off in your computer. Let’s understand a few points about this.
Turning off defrag. If you’re using Windows 7 or Mac OS X, then you’ve no problems. These operating systems will automatically turn off defragmentation for you if you’re using an SSD.
However, if you’re on Windows XP or Windows Vista – the operating system will NOT turn off defragmentation automatically. In fact, they can’t distinguish between SSDs and hard drives. It’s thus important for you to manually turn off defragmentation.
One thing to note is that if you’re running XP or Vista with a SSD (for your operating system and key applications) and a hard drive (for medias storage) within your computer, you should be EXTRA careful. If you’re defragging, do ensure you’re pointing to the hard drive and not the SSD
Turn on TRIM. Now, even though you’re not using defrag functionalities, you should still be aware you should enable something called “TRIM” to improve the performance of your SSD.
Most leading SSD manufacturers (e.g. OCZ and Samsung) include a TRIM feature (usually activated using their proprietary SSD software utility) to tell the computer which memory areas do not contain useful data. This allows the SSD to just delete the data and write in new data straightaway, without having to move the old data somewhere else. This ultimately results in better performance for your SSD.
I hope the above article has helped you understand that you should NOT defrag your SSD. Defragmentation is relevant only for things like hard disk drives which are slowed down when data sits all over the place.
In SSDs, this is not relevant. If you want to improve the performance of the SSD, you should enable the TRIM command instead.
That’s all I have for now. Until next time, have fun with your solid state drive!