Spotted: Samsung's 850 EVO SSD

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kinggremlin

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Here's a prediction you can take to the bank. It will be imperceptibly faster than its predecessor. SSD performance "innovation" has pretty much ground to a halt. There isn't anything that can really be done at this point to change the user experience for the better.
 

alidan

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Here's a prediction you can take to the bank. It will be imperceptibly faster than its predecessor. SSD performance "innovation" has pretty much ground to a halt. There isn't anything that can really be done at this point to change the user experience for the better.

use 2 sata ports and software that sets it up as a raid 0, there, just increased the speed by two... could probably have 4 way without to much extra cost too.
 

dovah-chan

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It's less about the increasing the user experience (which is already exceptional especially with the Samsung magician software which is wonderful) and more about pushing for higher capacities at lower price points as well as setting the standard for future drives to come.

 

kinggremlin

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use 2 sata ports and software that sets it up as a raid 0, there, just increased the speed by two... could probably have 4 way without to much extra cost too.

You have potentially doubled throughput, you have not doubled performance. What makes the SSD user experience so much better than traditional hard drives is not the higher throughput but the much quicker access time. Access time with SSD's is to the point it is nearly impossible to improve performance by a perceptible amount for every day computing.
 

alextheblue

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Here's a prediction you can take to the bank. It will be imperceptibly faster than its predecessor. SSD performance "innovation" has pretty much ground to a halt. There isn't anything that can really be done at this point to change the user experience for the better.
Modern SSDs are already awesome. Their performance doesn't need a major overhaul. Even with SATA, they have excellent transfer rates and more importantly rock incredibly high IOPS. Like Dovah-chan pointed out, what we need improved is the cost of high-capacity drives. If their 3D NAND eventually doubles capacity at all price points, I'm on board. I'd very much like to see a good quality 1TB SSD with decent performance hit the ~$250 mark. :)
 

childofthekorn

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Here's a prediction you can take to the bank. It will be imperceptibly faster than its predecessor. SSD performance "innovation" has pretty much ground to a halt. There isn't anything that can really be done at this point to change the user experience for the better.
Modern SSDs are already awesome. Their performance doesn't need a major overhaul. Even with SATA, they have excellent transfer rates and more importantly rock incredibly high IOPS. Like Dovah-chan pointed out, what we need improved is the cost of high-capacity drives. If their 3D NAND eventually doubles capacity at all price points, I'm on board. I'd very much like to see a good quality 1TB SSD with decent performance hit the ~$250 mark. :)

stop typing out this smut.
 

sewalk

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we need sata 4 or sas... sata 3 is too slow!
I dare you to actually sit down and document the difference in the user experience between using a Samsung 800-series SSD on a SATA-II port vs SATA-III. Then you can decide if we want Samsung to focus on developing a faster interface or if we'd rather have them focus on increasing density and economy so we can have TB SSDs as cheap as platter drives.
 

BulkZerker

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we need sata 4 or sas... sata 3 is too slow!
I dare you to actually sit down and document the difference in the user experience between using a Samsung 800-series SSD on a SATA-II port vs SATA-III. Then you can decide if we want Samsung to focus on developing a faster interface or if we'd rather have them focus on increasing density and economy so we can have TB SSDs as cheap as platter drives.

Something about PCIx interface based SSDs...
 
Since the vast majority of transfers on Windows are random reads of small files with queue depths of 1, we are seeing increasingly small real world differences between old SSDs and the latest models INCLUDING PCIe/M2 based drives. Is there any drive capable of delivering even a pathetic 50-100 MB/sec for random 4K reads at QD1?
 

xyriin

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Who cares about higher density unless they start packing more than 1TB in a drive.

No reason an 850 EVO couldn't offer a 2TB or 3TB capacity.
 

dovah-chan

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The reason the 840 EVO slows down is because it runs out of turbo cache space and then lowers the transfer speed. The 840 EVO isn't the best long term transfer performer and TLC is inherently less hardy or long lasting as MLC. Really turbo cache is both a blessing and a curse.

But the reason the drive became so popular is because of its cheap price, good overall performance, and nice feature set. Mix in that familiar Samsung brand name which naturally draws consumers towards your products and you've got a hot seller.

Also all drives generally reduce in speed after being over 50% full. Well now that might be a myth as I don't think no one has done any testing on that notion for SSDs but it's generally true for HDDs.
 

Tanquen

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The reason the 840 EVO slows down is because it runs out of turbo cache space and then lowers the transfer speed. The 840 EVO isn't the best long term transfer performer and TLC is inherently less hardy or long lasting as MLC. Really turbo cache is both a blessing and a curse.

But the reason the drive became so popular is because of its cheap price, good overall performance, and nice feature set. Mix in that familiar Samsung brand name which naturally draws consumers towards your products and you've got a hot seller.

Also all drives generally reduce in speed after being over 50% full. Well now that might be a myth as I don't think no one has done any testing on that notion for SSDs but it's generally true for HDDs.

I’m not 100% sure as I’m old and forgetful but… No, the EVOs slow down the moment you put data on them, some nonsense about the 3bit cells. The only time I got the 400MBs-ish reads was on the parts of the drive with no data. The over 50-70% thing is an SSD thing, hard disc drives don’t have that issue.
So, you are paying way more but:
It’s really slow with small files, it slows down the moment you put data on it, It’s un realistically slow after you’ve used it for a time and or it get 50%+ full, it’s not a real TB, even though you have to or should overprovision it and make it even smaller. So your 1TB drive is not 1TB it’s 900GB before you overprovision and you can’t use more than half of it without it slowing to a crawl. Then people think the SATA ports are too slow. Not even.
They lie (about all HDs) and say a GB is 1000MB, it is not! It is and always will be 1024MB. Even though Apple caved in a recent OS update as they were tired of support calls from people wanting to know why their 500GB drive was not 500GB. So your 1TB drive is not 1TB it’s 900GB. I’m old enough to remember when they lied (made up their own rules) and said something like, well a MB is 1024K until 100MBs or some such BS and then it’s 1000k and that’s why when you by RAM you actually get 32MB when you buy 32MB. Oh really, so when the file is in RAM it’s 1MB but when I save it to the HD it’s now 1.024MB. Right!
 

xyriin

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Some mixed information in here.

First off normal hard drives do slow down the closer to capacity they reach. The reason for this is because of the way conventional hard drives seek to read and write information on the platters. When the drive is empty they can simply write one bit right after the other. When the drive is closer to getting filled you may be able to write a few bits before you have to skip over existing written data to find the next empty spot. Similarly, when reading this information later you have to make the same skips in the sequential path resulting in wasted time. This is also why defragmenting your hard drive results in faster read speeds. Additionally, if you want to be able to defragment a hard drive you have to leave empty space as well. Additionally, hard drives experience further slow down the more full they are because as the information ends up further out on the platter, the seek takes longer to get out there to even start reading or writing your information even if you don't have a fragmented drive.

SSDs don't suffer the seek slowdown that hard drives do when they hold more information. What SSDs do suffer from is wear leveling. What causes this slowdown is when a SSD attempts to read information with worn NAND if it fails the first time it attempts to read again, which takes additional time. However, modern SSDs eliminate this issue with over provisioning, wear leveling, and garbage collection. While SSDs don't need to defrag, they still need this same space for a different reason and that is to perform all the maintenance tasks like garbage collection. It's also key to note that NAND wear is caused by write operations. Unless you're using SSDs in a server capacity or intensive disk writing like maybe video production your never going to see appreciable wearout of the NAND in your drive. Casual use or gaming should never experience SSD slowdown (inside of a 10-15 year period) as long as you have a quality SSD with the firmware and an OS that properly supports the maintenance functions.

So in summary to maintain top SSD speed you need to leave the 10% or so free for the maintenance operations and you're good to go with no slowdown. For a hard drive you need to leave the 10% or so free for defragging and you still get to deal with slowdowns as the drive is filled to capacity. End result both storage mediums need 10% overhead (neither wins) but conventional hard drives still experience slowdown.

As for listed drive size that is just marketing BS taking advantage of the 1k to 1024 difference. It's long been practice to manufacturers to list physical space and not formatted capacity.
 

xyriin

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That is perfectly valid information however you'll notice that it only affects write performance. For normal users writes are a very insignificant portion of typical drive use. Additionally, this is a slowdown of the 'turbo' mode not in inherent slowdown of the NAND itself. Think of this as an artificial technology like RAID striping where you increase effective speed but still don't exceed the speed of the actual medium. It's just like a buffer on any other drive. If you read the graph you'll also see that even on the 120GB model you are able to write for approximately 5 seconds at 500MB/s. How often are you doing sequential WRITES on a drive with more than 2.5GB? The answer is never unless you're doing video production work, in which case you're using a higher capacity SSD anyway. Those doing that case specific video production work using the same technology 1TB model can perform 11GB of sequential writes before capping the buffer.

The only file sizes a normal user will ever see that could exceed that buffer capacity would be game installs or transfer of HD video. Let's say you install a 20GB game via Steam. Doesn't matter, what is your internet speed? 25/5, 50/25, 100/50? Even 100Mb/s internet means you download at a peak of 12.5MB/s...which will never reach the capacity of your SSD. How about gigabit internet? Again you peak at 125MB/s still well below the buffer. Installing from a disc won't matter either as your optical drive stupidly slow compared to the SSD. Want to transfer files across your local network? Again same scenario as even ethernet has you running at 100/1000Mb/s (12.5/125MB/s). Have a large movie on your computer that you want to transfer from one drive to another? Well if you're transferring from a normal hard drive it doesn't matter, the speed cap on a mechanical disk won't exceed the buffer. Now going from one SSD to another SSD would present a potential slowdown but how large is your file? Are you writing enough sequential data to cap the buffer...probably not.

The 840 EVO slowdown is mainly a theoretical problem. As the article clearly states the buffer size varies from 2.5% of 120GB model to 1.2% of the 1TB model. So to maintain performance on a mechanical drive for defragging you need to save approximately 10%, garbage collection plus a turbo write buffer is going to come in well under that. So a SSD needs less overhead and still doesn't have the read slowdowns like a mechanical drive. Sure a SSD could experience a drop in write speed in extreme benchmark situations but it's not a normal scenario.
 
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