The Samsung SSD 850 120GB Review: A Little TLC for SATA
by Billy Tallis on November 27, 2017 12:00 PM ESTAnandTech Storage Bench - Light
Our Light storage test has relatively more sequential accesses and lower queue depths than the Heavy test, and it's by far the shortest test overall. It's based largely on applications that aren't highly dependent on storage performance, so this is a test more of application launch times and file load times. This test can be seen as the sum of all the little delays in daily usage, but with the idle times trimmed to 25ms it takes less than half an hour to run. Details of the Light test can be found here. As with the ATSB Heavy test, this test is run with the drive both freshly erased and empty, and after filling the drive with sequential writes.
The Samsung SSD 850 120GB manages to deliver an average data rate that is slightly higher than even the 128GB 850 PRO on the Light test, when the drives are empty. On a full drive, the 850 PRO retakes the lead.
The average and 99th percentile latencies of the Samsung 850 120GB are not the best, but like the other Samsung drives it doesn't experience a catastrophic breakdown of performance when full. The drives using Micron 3D TLC all lose control over latency.
The 850 120GB shows a substantial difference in average read latency between test runs with a full or empty drive. The average write latency is completely unaffected, while the Micron 3D TLC drives end up stalling write commands when their write buffers overflow.
The 99th percentile latency figures further emphasize the difference in behavior between the Samsung drives and the SMI+Micron drives. All of them perform fine in ideal conditions, but the Samsungs are much better at handling the pressure of operating while full. The 850 PRO 128GB and the 850 EVO 250GB show a much smaller impact to read latency than the 850 120GB and the other two Samsung 120GB TLC drives.
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Kristian Vättö - Monday, November 27, 2017 - link
There are still MLC based enterprise SSDs from Samsung, such as SM863a.yifu - Saturday, December 2, 2017 - link
also Toshiba hk4rqlum - Monday, November 27, 2017 - link
For the pc's at work I always use 120gb ssd's as they offer enough capacity and are still about €20 cheaper then 200gb+ drives.bug77 - Tuesday, November 28, 2017 - link
I'm not sure giving up 80GB (40%) space to save €20 is the right choice. Remember, these things don't like being full and people tend to save a lot of junk of their drives.That said, the smallest SSD is still way better than the fastest HDD. (Have you ever seen Win10 trying to patch itself while installed on a HDD?)
ads295 - Tuesday, November 28, 2017 - link
I think that's why laptops started skipping on the HDD activity LED from as early as when Win8 was available.bcronce - Tuesday, November 28, 2017 - link
Great for my firewall. I only need ~4GiB of space.Glaurung - Tuesday, November 28, 2017 - link
"Remember, these things don't like being full and people tend to save a lot of junk of their drives."For situations where the drive is never going to be full and you just need the cheapest possible SSD, it's fine. For instance, My spouse writes reports for a living, and she has never come anywhere near to filling up the 40gb X25-V on her work laptop. (no music, no pictures, no videos, just documents and PDFs and audio recordings that she refers to and then deletes when the report gets final client approval).
pixelstuff - Monday, November 27, 2017 - link
We've been missing the 128GB 850 Pro model with it's 10 year warranty, which usually cost about $90. We were using it in single task devices such as DVRs with secondary data drives. Having to move to the 256GB 850 Pro just meant we had to spend an extra $30+ for no extra benefit, and unfortunately those 256GB drives never dropped to the $90 price range.mapesdhs - Wednesday, November 29, 2017 - link
Pricing did drop that low at one point; in the UK the 850 EVO 250GB was 53 UKP from Amazon and not much more elsewhere (meanwhile, 500GB pricing was slowly heading down to 100 UKP), but then after a blowout sale of several thousand 850 EVO 500GB units by one retailer in two weeks at around 115 UKP each (I bought two), I'm sure Samsung realised they simply didn't need to sell their tech so cheap, prices went up, and all the other vendors followed suit. Also, when new models came out, old models were almost immediately removed from seller sites, sometimes on the same day. Since then, pricing has almost doubled, there's just no need for the manufacturers to offer low pricing when they can easily sell everything they make due to OEM demand. It's ironic that the nature of that demand is largely by a consumer demographic that treats tech as thoroughly disposable, and often has little regard for what it is or how it works.The more I see new products like this being worse than old products, the more I'm impressed with what Intel has done with Optane, etc. At least Intel has actually done something new, whereas Samsung seems to have done what Intel did with its CPU-based strong position, ie. sat on its butt for several years while the cash rolled in and not bothered to innovate. Have to wonder why Samsung couldn't have brought ought something like Optane ages ago, and for the consumer market, not just Enterprise. Yes there's a shift towards NVMe, but it's not that big yet (with warranties 50% shorter and insane price hikes on retail versions), and a lot of consumers just want capacity with decent quality. At this point a 4TB SATA SSD with the quality level of the 850 EVO would sell very well if sensibly priced, but nobody's even trying, they're still having fun selling low capacity models (why sell one 4TB when one can make a lot more selling twenty 120GB units). I remember SanDisk promised to have an 8TB model by now, but that never happened.
Billy, add the old 840 and 840 Pro into those results charts, I bet this new 850 wouldn't look so impressive, ditto if other old models were included too like the Vertex 4, Vector, Neutron GTX, etc. Heck, even the old 830 would likely put most of the modern non-Samsung models to shame (ditto something as ancient as a Vertex3, and it'd be hillarious too see where the budget Agility3/4 would fit in the charts today). SATA SSDs have become like CPUs before Ryzen finally launched, the tech has stagnated or even gone backwards. The 750 was touted as a cheaper 850 EVO, but in reality it became more expensive. I get that the nature of parallelism in NAND means larger dies don't offer the performance at lower capacities, but then that's why it would make sense to create something genuinely new; Intel needed a good poke in the ribs from Ryzen to get moving again with its CPU line, but at least it *did* something with respect to developing new storage tech.
Ian.
WithoutWeakness - Monday, November 27, 2017 - link
First section header in the introduction: The *Samung* SSD 850"