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Results: Tom's Hardware Storage Bench

Samsung 840 EVO mSATA Review: 120, 250, 500, And 1000 GB, Tested
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Storage Bench v1.0 (Background Info)

Our Storage Bench incorporates all of the I/O from a trace recorded over two weeks. The process of replaying this sequence to capture performance gives us a bunch of numbers that aren't really intuitive at first glance. Most idle time gets expunged, leaving only the time that each benchmarked drive is actually busy working on host commands. So, by taking the ratio of that busy time and the the amount of data exchanged during the trace, we arrive at an average data rate (in MB/s) metric we can use to compare drives.

It's not quite a perfect system. The original trace captures the TRIM command in transit, but since the trace is played on a drive without a file system, TRIM wouldn't work even if it were sent during the trace replay (which, sadly, it isn't). Still, trace testing is a great way to capture periods of actual storage activity, a great companion to synthetic testing like Iometer.

Incompressible Data and Storage Bench v1.0

Also worth noting is the fact that our trace testing pushes incompressible data through the system's buffers to the drive getting benchmarked. So, when the trace replay plays back write activity, it's writing largely incompressible data. If we run our storage bench on a SandForce-based SSD, we can monitor the SMART attributes for a bit more insight.

Mushkin Chronos Deluxe 120 GB
SMART Attributes
RAW Value Increase
#242 Host Reads (in GB)
84 GB
#241 Host Writes (in GB)
142 GB
#233 Compressed NAND Writes (in GB)
149 GB

Host reads are greatly outstripped by host writes to be sure. That's all baked into the trace. But with SandForce's inline deduplication/compression, you'd expect that the amount of information written to flash would be less than the host writes (unless the data is mostly incompressible, of course). For every 1 GB the host asked to be written, Mushkin's drive is forced to write 1.05 GB.

If our trace replay was just writing easy-to-compress zeros out of the buffer, we'd see writes to NAND as a fraction of host writes. This puts the tested drives on a more equal footing, regardless of the controller's ability to compress data on the fly.

Average Data Rate

The Storage Bench trace generates more than 140 GB worth of writes during testing. Obviously, this tends to penalize drives smaller than 180 GB and reward those with more than 256 GB of capacity.

Each of Samsung's mSATA-based drives is pitted against a 2.5" 840 EVO equivalent, which I'm highlighting in red. The 120 and 250 GB models yield almost identical results using both interfaces. But that changes as we ascend the chart; the 500 and 1000 GB mSATA-based 840 EVOs fall behind the 2.5" drives. It's possible that firmware plays a role, but I suspect that the work needed to enable high capacities on mSATA has something to do with it.

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  • 2 Hide
    vaughn2k , February 24, 2014 12:31 AM
    Now all we need is the price to drop, then I'll get one.. ;) 
  • 0 Hide
    blackmagnum , February 24, 2014 1:30 AM
    Maybe it's time to upgrade the HD of an old working notebook to SSD! But will a Core2Duo processor bottleneck a SSD?
  • 2 Hide
    jrharbort , February 24, 2014 2:01 AM
    @blackmagnum: You don't have to worry about your processor being a bottleneck, but rather, your system's SATA interface. It is highly doubtful that your Core 2-based notebook (much like my own) has an m-sata slot, and the 2.5" bay for a HDD would have a SATAII port, not SATAIII. So the overall max read/write rates would be cut in half. But to answer your question in another way, tom's posted an article almost a year ago on the subject of upgrading older systems with an SSD: http://www.tomshardware.com/reviews/ssd-upgrade-sata-3gbps,3469.html
  • 1 Hide
    spookyman , February 24, 2014 6:08 AM
    @blackmagnum: You be glad to upgrade your hard drive to a SSD drive. Did it for my goddaughter's after she had a hard drive crash and it runs a lot faster then before.
  • 0 Hide
    JohnnyLucky , February 24, 2014 6:16 AM
    Interesting article. It coincides with the current shift from desktop pc's to mobile pc's.
  • 0 Hide
    nekromobo , February 24, 2014 6:56 AM
    But aren't we already moving to M.2. Why can't I buy Samsung XP941 :( 
  • 0 Hide
    pyro226 , February 24, 2014 7:25 AM
    "The latest version offers RAPID support to non-EVO drives like the 840 Pro."Got my hopes up there. The standard 840 series SSDs are NOT supported. The article didn't explicitly state they were, but what other drives (aside from the 840 Pro and EVO) have Rapid support? Perhaps "The latest version offers RAPID support to both EVO and 840 Pro SSDs." would be more accurate.
  • -1 Hide
    LordConrad , February 24, 2014 10:50 AM
    "This company has a track record of disrupting the markets it enters; now that it's focusing attention on smaller form factors with enthusiast-class hardware, it's only a matter of time before we start seeing M.2-based offerings as well."This is mainstream hardware, I don't know any enthusiats who will settle for drives with TLC NAND.
  • 0 Hide
    lowguppy , February 24, 2014 1:52 PM
    It is nice to see these finally available. I've been watching the Crucial m500 mSATA drive for a while, and the 480gb version frequently falls under $300 on NewEgg, which is competitive with 2.5" SSDs.
  • 2 Hide
    RedJaron , February 24, 2014 2:04 PM
    Quote:
    This is mainstream hardware, I don't know any enthusiats who will settle for drives with TLC NAND.

    "Enthusiast" to me doesn't automatically mean getting the fastest, biggest, bestest, craziest parts regardless of price. It also means people who put a lot more thought into their systems and thoroughly weigh all their options. MLC, TLC, or not, the fact remains that the EVO is a fast, reliable drive for a good price.

    Your argument sounds similar to, "I don't know any enthusiasts who will settle for LGA 1150 instead of LGA 2011," or "I don't know any enthusiasts that would settle for a non-K CPU."
  • 1 Hide
    DonQuixoteMC , February 24, 2014 5:32 PM
    I was just thinking last night: "Wouldn't it be great if there were mSATA 840 EVOs?"Funny coincidence.
  • 0 Hide
    slipslip , February 25, 2014 11:29 AM
    I've been curious about these mSATA drives since I realized that my Thinkpad T420 (from 2011) had an empty mSATA drive. My understanding is that it is SATA II, though, not SATA III, whereas the main HDD slot is SATA III. Would I be better off just getting a 2.5 SSD for the main slot, or would it work to get a smaller mSATA (say 128gb) and then a larger capacity HDD for the 2.5 slot?
  • 0 Hide
    pyro226 , February 25, 2014 12:47 PM
    Quote:
    I've been curious about these mSATA drives since I realized that my Thinkpad T420 (from 2011) had an empty mSATA drive. My understanding is that it is SATA II, though, not SATA III, whereas the main HDD slot is SATA III. Would I be better off just getting a 2.5 SSD for the main slot, or would it work to get a smaller mSATA (say 128gb) and then a larger capacity HDD for the 2.5 slot?
    Really depends on how much space you need and how easily the computer can boot off of the mSATA port. Frequently, the bios doesn't have an option to boot from mSATA. Your easiest bet would probably be a 2.5" 250GB+ SSD. 128 GB is a bit small if you have a lot of games.Information on how to set up an mSATA boot.http://blog.laptopmag.com/triple-your-speed-how-to-install-an-msata-ssd-boot-drive-in-your-laptop?cmpid=492396(Referenced from: http://www.tomshardware.com/forum/270102-32-useful-articles-part#10663269)
  • 0 Hide
    slipslip , February 25, 2014 1:25 PM
    Thanks pyro226. I've got a 5400 250GB HDD in the 2.5 bay now, and it is really pushing up against the top of its capacity (photos and videos, plus some large datasets) and it is REALLY creaking along. I've been waiting for the prices of the 250 or 480GB SSDs to drop, and for the longest time they just seemed to plateau at around $0.75-$1/GB. Now I'm starting to see more substantial drops in the prices at those capacities (down to ~$0.55/GB), and they may have finally dropped into my price range.

    Since I don't have the budget for a new machine, I might just try to resurrect this one with a $150-250 investment in a new SSD.



  • 0 Hide
    slebel , March 13, 2014 5:37 PM
    Anyone have a bead as to when the ssd will be available on the pci-e 2 format?