Mixed Random Read/Write Performance

For full details of how we conduct our Iometer tests, please refer to this article.

Iometer - Mixed 4KB Random Read/Write

In mixed 4KB random performance the 2TB Pro shows rather significant gains over the 512GB model. I was always surprised how poorly the 850 Pro performed in this test, so it's good to see Samsung paying attention to this, especially since the performance increase comes with dramatically improved power efficiency.

Iometer - Mixed 4KB Random Read/Write (Power)

Samsung 850 Pro 2TB

The 512GB Pro had performance and power issues once over half of the IOs were writes, but the 2TB model shows quite optimal performance scaling.

Mixed Sequential Read/Write Performance

Iometer - Mixed 128KB Sequential Read/Write

In mixed sequential workload performance of both the 2TB Pro and EVO is further improved with the Pro topping the chart. The 2TB EVO is again more power efficient than the 1TB model, whereas the 2TB Pro consumes only a little more power than the 512GB model (this was expected because large sequential IOs utilize multiple dies and with 2TB having more NAND there are more dies drawing power).

Iometer - Mixed 128KB Sequential Read/Write (Power)

The improvement has been in the critical 60/40 and 40/60 distributions. Quite a few drives have an infamous "bathtub" curve where performance severely degrades, but the 2TB Pro and EVO are fairly consistent though all distributions. It's great to see Samsung improving mixed performance because typically it has been an area that has been forgotten in client SSDs, but under real world workloads IOs tend consist of both reads and writes.

Samsung 850 Pro 2TB
Sequential Performance Idle Power Consumption, ATTO & AS-SSD
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  • SviatA - Friday, August 21, 2015 - link

    As I see it, Samsung is pushing really hard to win over the whole market. The 850 Evo line is a substantial step forward. I really like the way PC starts working with an SSD rather than with HDD.
    I've bought one here http://hardware.nl/harde-schijven/samsung/ssd/mz-7...
    But you may find even a better offer on eBay, I think. Anyway, even for 85 euro this is a great purchase.
  • htwingnut - Saturday, September 19, 2015 - link

    Can someone please explain the "Performance Consistenty" charts and how to read them? They change every time I switch the default and 25% OP even with the same drives... confusing.
  • joyce.shue@verizon.net - Thursday, October 15, 2015 - link

    I purchased the Samsung SSD 850 Pro to install in my new Windows 10 computer. I can't clone Windows 10 or anything to this drive. I've talked to Samsung for over 7 weeks and keep getting a new date for the release of their cloning software. I've tried 2 different cloning software and they don't work with this drive. Until Samsung updates the software for Windows 10 DON'T BUY.
  • Miller1331 - Tuesday, December 1, 2015 - link

    Using 2 of these in a music production rig and they are monsters
  • Meteor2 - Wednesday, November 23, 2016 - link

    I don't think this reviews specifies what interface the 850 Pro uses anywhere.
  • Meteor2 - Wednesday, November 23, 2016 - link

    ...until the last page. Would've thought it page 1 material, myself.

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