Hi everyone,
as my thread from yesterday about shredding SSD’s the right way already was very helpful, another follow-up topic came to my mind, which may also be interesting for me and maybe others too.
Since many PC’s often use SSD’s and less harddrives nowadays it may be interesting to discuss the full-disk encryption of it.
First of all some questions, which came to my mind:
- Does the encryption of a SSD decrease its performance (read/write-speed) significantly?
- How does the encryption affect the wear-leveling of the SSD and what should be considered to ensure a safe encryption?
- Will functionalities like hibernation still work? Are maybe other functionalities affected in a negative way?
I already successfully full-disk encrypted my old laptop (harddrive) with the instructions from StackExchange. My computer has a 1TB SSD + 1TB harddrive and I wish to encrypt completely everything, that’s not technically necessary. I want to use Debian as my distro. Could this instruction work the same way as with harddrives?
I’m interested in your knowledge about this.
~sp3ctre
I am using MX Linux (Debian based) and at install I chose FDE, just with the GUI it’s easy to have LUKS+btrfs, nothing special to do. Encryption is done by hardware, your CPU has AES instructions that can encode/decode gigabits/s and is not a bottleneck at all.
How does the encryption affect the wear-leveling of the SSD and what should be considered to ensure a safe encryption?
LUKS, or rather Device Mapper for crypto devices does not enable trim by default, you need to enable it separately.
the LUKS wiki also has some general tips, and some for SSDs specifically: https://gitlab.com/cryptsetup/cryptsetup/-/wikis/FrequentlyAskedQuestions
I’m confused by some of your questions, but it seems you are thinking that HDD vs SSD in the context of encryption is different, but it is functionally the same. Any perceived performance difference by percentage on HDD would be the same or better on SSD.
I don’t think you’d perceive any slowdowns from encryption unless you’re doing very specific types of work and hitting the disk util hard, and even it would probably only be a few percentage points of difference between encrypted and unencrypted.
You can find versions benchmarks online to compare different filesystem types and settings compared.
Hehe, no stupid questions I guess! When googling about this type of stuff, I often stumble across some claims I simply cannot verify myself. Some people say it’s unsafe, some people say it slows down everything and so on and some answers are from >10 years ago, so I feel the need to clarify what’s the status quo. Thanks for your view on that.
It’s safe.