SSD Controllers as Fast As Possible

Techquickie ·Techquickie ·2017-05-06 · 899 words · ~4 min read
Floatplane YouTube

Transcript

JSON SRT VTT 68
0:00 If you're in the market for an SSD or solidstate drive, chances are that
0:04 you're thinking about things like capacity and speed. But if you've ever
0:08 read a more in-depth review of an SSD, you've probably seen talk about drive
0:13 controllers and how they have the potential to make or break a drive's
0:17 overall performance. But what exactly is a drive controller? Well, think of it
0:22 this way. If you were to go to the local hardware store and just buy a toolbox,
0:27 it's not very useful unless you're putting stuff in it. And while it's
0:31 possible to use your toolbox just by dumping stuff in it willy-nilly, you'll
0:36 get a lot more out of your general toolbox experience by sorting your
0:40 pliers and nails and whatnot into the little compartments. So, it'll be easier
0:45 to find stuff when it comes time to tackle your next big project. This
0:49 process of sorting your stuff in a storage container is very similar to
0:52 what an SSD controller does. Just like a toolbox can't sort the tools itself, the
0:58 flash cells on your SSD that store data need something that can fill them up
1:02 sensibly with ones and zeros and talk to
1:05 the rest of your computer. The SATA data connector on your SSD is wired directly
1:10 into your SSD's controller, which processes the data and then sends it to
1:14 your drive's flash memory. So, because the controller is responsible for
1:18 actually putting data onto the SSD, lower-end ones can create a bottleneck
1:22 or even be less reliable due to hardware
1:26 and/or firmware differences. Unfortunately, the reasons behind why
1:30 one controller is better than the other aren't always clear because
1:34 manufacturers treat controller designs like trade secrets. So, it's a little
1:38 hard to analyze Sandforce's signature blend of 11 herbs and spices compared to
1:43 Samsung's secret sauce that actually just turns out to be Thousand Island.
1:49 But what we can tell you is that nicer controllers in higherend drives are
1:54 connected to many memory cells at once
1:57 for faster throughput. A little bit like how GPUs contain many compute cores that
2:02 work in parallel to help you get higher frame rates. But what are some of the
2:06 other important ways a controller keeps data flowing smoothly? Well, one of
2:11 these is wear leveling. Unlike a traditional mechanical hard drive that
2:15 will generally last until the moving parts wear out, SSD flash cells can only
2:19 be written and rewritten so many times. So, imagine a shelf. Instead of always
2:25 putting data on the lowest, easiest to reach one, the controller will try to
2:30 write all cells evenly to extend the usable life of the drive as a whole.
2:35 Controllers also handle a couple very important features called garbage
2:39 collection and trim. Unlike hard drives
2:42 where data can just be overwritten at will, SSDs store data in blocks that
2:46 must first be erased before new data can be written. Garbage collection handles
2:51 this by marking certain parts of data within the block as stale if they're
2:56 okay to be replaced with newer data. Moving the remainder of the still good
3:01 data to a new block, then finally erasing the old one. The problem with
3:06 this is that when you go to delete a file, garbage collection doesn't mark
3:10 the deleted data as stale. So, garbage collection actually keeps copying this
3:15 data to new blocks, needlessly using up
3:19 write cycles. This is where trim comes in. An operating system command that
3:23 tells your SSD controller which pieces of data within a block are actually
3:28 parts of deleted files so they won't stick around. both improving performance
3:33 and increasing the lifespan of your drive, which is critical if you want
3:38 your SSD to last the four years it needs
3:41 to so it can store an entire election cycles worth of dank memes. Speaking of
3:47 that, Squarespace, simple, powerful, beautiful 24/7 live chat support and
3:51 email if you need help setting up your website that you can get for $12 a
3:55 month. And if you buy a year, you get a domain thrown in with that website as
3:59 well. When you're setting things up, there's responsive design so that your
4:03 website that you're building based off one of their many awesome templates will
4:07 look great on a huge variety of devices. And if you want to sell something, you
4:11 can do that as well using their commerce module. If you just want one single page
4:16 that just looks really good, you can use their cover page module, which also
4:20 works just great. And now they have Squarespace Start, an app that allows
4:24 you to create a simple onepage site that I just kind of referenced from your
4:28 mobile device. You can start a trial with no credit card required and start
4:32 building your website today. And if you do, use offer code techquickie to get
4:36 10% off your first purchase. All right, guys. If you like this video, like it.
4:40 If you dislike this video, do that thing. Uh, get subscribed if you want to
4:43 see more of our content. Comment down below with other stuff that you'd like
4:46 us to see cover on the TechQuy channel.
4:50 Uh, check out Channel Super Fun because they're cool.