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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boozed - Monday, November 27, 2017 - link
This website really needs a "send corrections" link...mr_tawan - Tuesday, November 28, 2017 - link
corrections is a kind of participation. Using comments is not that bad idea.dgingeri - Monday, November 27, 2017 - link
This sounds like a great OS drive for servers. They don't change all that much, especially if the logs are offloaded to a different drive.sonny73n - Tuesday, November 28, 2017 - link
TLC for servers? No thanks.dgingeri - Wednesday, November 29, 2017 - link
Why not? Write endurance is not a factor when dealing with the boot/OS drive, especially when logs are moved onto another drive. Most servers would see 10-15GB of writes per week on the OS drive, with updates bumping that up more once in a while. This drive would last for decades at that write level.tmanini - Tuesday, November 28, 2017 - link
meh - while there is nothing wrong with one as a boot drive only: once booted you won't benefit much. (this is not a reflection for complex server environs - which then you would never consider this SSD as a contender)lilmoe - Monday, November 27, 2017 - link
The EVOs are priced down on amazon now. Just saying.Magichands8 - Monday, November 27, 2017 - link
They better be. Nothing much to see here.lilmoe - Monday, November 27, 2017 - link
I know... I like Sammy and all, but I'd like to see them go even lower. 2TB SSDs shouldn't be a luxury anymore.mapesdhs - Wednesday, November 29, 2017 - link
Still a very long way from where they used to be. 850 EVO 250GB is currently 85 UKP on Amazon; before the pricing went crazy it was 53 UKP.