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Benchmark Results: 4 KB Random Performance (Response Time)

Samsung Goes 6 Gb/s: Is The 830-Series SSD King Of The Hill?
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It's wrong to look at data rates (throughput) without taking latency and processing time into account. We've explained this before in our tablet reviews with regard to Wi-Fi throughput, but the same concept can be applied to storage. Let's go back to the analogy of a phone call, because it helps illustrate why there's more to speed than just raw bandwidth.

Throughput can be roughly compared to audio quality. Latency is represented by the amount of time that passes between you speaking into the phone and the person on the other side hearing you, and processing time is the delay that happens when that person things about a response and answers back.

Applied back to SSDs, throughput is the amount of data you can send over time, latency is the lag due to data transmission, while processing time is the overhead incurred by the controller.

Now consider that latency plus processing time equals response time. That's really what we're measuring in Iometer. This can get confusing because Iometer uses the terms latency and response time interchangeably, but it's really only capable of measuring the latter.

In random reads, the 256 GB 830 has a response time of about .10 ms, which puts it in line with OCZ's 120 GB Vertex 3 and Agility 3. That's 30% slower than what we see from higher-capacity m4s. In comparison, other second-gen SandForce SSDs (including the 240 GB Vertex 3) have response times slightly under .20 ms. Turning to random writes, the 256 GB 830 continues to have a response time around .10 ms, which is slightly slower than the 256 GB m4 and 240 GB Vertex 3.

Response time is a measure of the difference between initiating and completing an operation, while throughput is a measure of the amount of data transferred. These two values affect performance in different ways, but they don't stack up. So, it's not like the 64 GB m4 "feels" 75% slower than the 128 GB m4 (25% slower throughput plus 50% slower response time). Throughput and response time usually correlate in that you get high throughput with low response time.

The maximum response time gives us a look at the extremes. In random reads, the Crucial m4s all lead, but the 830, SSD 510, Wildfire, and Chronos Deluxe aren't too far behind.

The 256 GB Samsung 830 has a maximum write response time of 28 ms, which is lower than most SandForce drives, but higher than Crucial's m4s. The relatively high response times on SandForce-based SSDs indicate that there's more garbage collection occurring immediately after every write operation. Crucial predominately focuses on background garbage collection, which explains how the m4s achieve lower maximum write response times. Samsung falls in between, demonstrating a balance between foreground and background garbage collection. 

This is a double-edged sword. You can either perform garbage collection right after a write access or postpone the action to when the drive is idle. If you rely more heavily on idle (background) garbage collection, performance goes up at the cost of increased write amplification. Conversely, active (foreground) garbage collection minimizes write amplification, but impacts performance.

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  • 20 Hide
    pbrigido , September 23, 2011 12:12 PM
    With all of these fast SSDs coming to market, I can only hope that the competition starts to drive down prices soon.
  • 20 Hide
    kikireeki , September 23, 2011 2:00 PM
    When will we be seeing articles like: SSD price slashed 50%?
Other Comments
  • 20 Hide
    pbrigido , September 23, 2011 12:12 PM
    With all of these fast SSDs coming to market, I can only hope that the competition starts to drive down prices soon.
  • 0 Hide
    Anonymous , September 23, 2011 12:16 PM
    I still opt for the M4 in all the enthusiast builds I do!

    It boils down to reliability, not one hiccup on M4 yet (or any crucial drive Ive installed), 4/5 Sandforce drives I have installed have had some form of callback problem to resolve once deployed, mostly requiring firmware updates, but a few failed drives as well!

    Mind you, still better than the early Corsair force Series I used, every single one failed! Stopped using them quick!

    Am tempted by OCZ, once they have reliability on their side I will give them a go again!
  • 0 Hide
    Anonymous , September 23, 2011 12:57 PM
    Would love to see an article addressing Sandforce controller problems people have been experiencing.
  • 6 Hide
    mark_hamill , September 23, 2011 1:00 PM
    Would love to see an article addressing Sandforce controller problems people have been experiencing.
  • 3 Hide
    JamesSneed , September 23, 2011 1:02 PM
    Looks like a really nice SSD. Samsung has one of the best validation proceses along with Intel and Crucial so I really don't expect people to have issues like they do with OCZ drives. Now the real question how much will it be on the egg?

    I saw this quote below in the summary and laughed as nobody in there right mind would use a basic MLC drive in a database server. So Samsung tuned the drive for what it will be used in ,desktops, good.
    "Although we'd probably think twice before picking this as our first choice for a database server, it does just fine in an enthusiast's machine."
  • 20 Hide
    kikireeki , September 23, 2011 2:00 PM
    When will we be seeing articles like: SSD price slashed 50%?
  • -1 Hide
    JohnnyLucky , September 23, 2011 2:36 PM
    great review. now we just have to wait and see how the ssd will hold up over the long haul. If it is anything like the 470, then it should be problem free.
  • 0 Hide
    alikum , September 23, 2011 2:48 PM
    Make it $1 per GB at least
  • -3 Hide
    beenthere , September 23, 2011 3:04 PM
    We'll see how this series of Samsung SSDs fair. The previous gen was a nightmare of problems so I don't think Samsung's validation process is any better that the rest of the SSD suppliers - which is sad when Samsung controls everything including NAND production. It's amazing that we still have SSDs NOT readt for Prime Time.
  • 2 Hide
    AppleBlowsDonkeyBalls , September 23, 2011 4:53 PM
    beenthereWe'll see how this series of Samsung SSDs fair. The previous gen was a nightmare of problems so I don't think Samsung's validation process is any better that the rest of the SSD suppliers - which is sad when Samsung controls everything including NAND production. It's amazing that we still have SSDs NOT readt for Prime Time.


    Proof? I think you just pulled this out of your ass or from someone's that told you some story. The 470 series was VERY reliable.
  • 0 Hide
    Kamab , September 23, 2011 5:06 PM
    I've stuck with Intel and crucial drives on rigs that I had any decision on, but it's always nice to see a little competition. I expect prices will continue to drop pretty linearly over the next few years.
  • 0 Hide
    David 617 , September 23, 2011 5:21 PM
    ahh, its always refreshing to see a newer and faster SSD.
  • 0 Hide
    yurim , September 23, 2011 5:29 PM
    What is the physical height of the drive, is it 7 or 9.5 mm? I want to know if it will fit in a ThinkPad x200.
  • 0 Hide
    acku , September 23, 2011 5:51 PM
    yurimWhat is the physical height of the drive, is it 7 or 9.5 mm? I want to know if it will fit in a ThinkPad x200.


    7mm but it comes with a spacer to fit 9.5mm
  • -2 Hide
    belardo , September 23, 2011 6:53 PM
    Performance matters, but reliability over-rules that.

    Even today, I would NOT use OCZ drives on any computer. Yeah, they are generally the fastest drives on the market, but I'd rather get an intel, even an M2-X25. The return rates for ALL drives, other than intel... are bad. Samsung is worst in performances and tools. But this new drive... we'll have to see over time.
  • 0 Hide
    cmartin011 , September 23, 2011 7:20 PM
    Another two years before we meet dollar 1gb range for high performance ssd
  • 0 Hide
    ikyung , September 23, 2011 7:26 PM
    belardoPerformance matters, but reliability over-rules that.Even today, I would NOT use OCZ drives on any computer. Yeah, they are generally the fastest drives on the market, but I'd rather get an intel, even an M2-X25. The return rates for ALL drives, other than intel... are bad. Samsung is worst in performances and tools. But this new drive... we'll have to see over time.

    Really? Hmm, this is the first time I heard something negative about the 470series SSD. Everytime I read a SSD article the 470series always had good reviews on solid reliability.
  • 0 Hide
    JohnnyLucky , September 23, 2011 7:45 PM
    belardoPerformance matters, but reliability over-rules that.Even today, I would NOT use OCZ drives on any computer. Yeah, they are generally the fastest drives on the market, but I'd rather get an intel, even an M2-X25. The return rates for ALL drives, other than intel... are bad. Samsung is worst in performances and tools. But this new drive... we'll have to see over time.



    I have googled every which way and cannot find any references to any major problems or issues with the 470 series that is similar to what other brands have been going through.
  • -2 Hide
    boletus , September 23, 2011 9:03 PM
    I'll be watching the customer feedback on objective forums wrt reliability (certainly not mfgr-reported failure rates, which Tom's, and reality, have demonstrated to be useless). If these new Sammys can approach Intel's level of customer satisfaction, it will be a great step forward for SSD technology. If not, well just another pipe dream for those that value reliability over speed.
  • -2 Hide
    beenthere , September 23, 2011 9:13 PM
    All you need to do is read the actual owner reviews to know that Samsung a has had a ton of problems with their SSDs, similar to the other SSD suppliers. See Newegg, Samsung, etc. for user reports. I sure hope these folks finally invest the necessary effort to correct all of these SSD issues or I'm not buying their crap.
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