6Gbps Performance

I installed the Intel SSD 510 in a 15-inch 2011 MacBook Pro as well as a 15-inch 2010 MacBook Pro to put together a 3Gbps vs. 6Gbps performance comparison. I turned to Xbench for some quick and dirty performance data:

SATA Performance—XBench 1.3
Intel SSD 510 250GB 3Gbps (2010 15-inch MBP) 6Gbps (2011 15-inch MBP) 6Gbps Advantage
4KB Sequential Write 157.8 MB/s 192.2 MB/s +21.8%
256KB Sequential Write 182.0 MB/s 257.1 MB/s +41.3%
4KB Sequential Read 32.5 MB/s 32.7 MB/s 0.0%
256KB Sequential Read 197.3 MB/s 315.6 MB/s +60.0%
4KB Random Write 47.8 MB/s 49.0 MB/s +2.5%
256KB Random Write 186.4 MB/s 260.9 MB/s +40.0%
4KB Random Read 14.5 MB/s 13.4 MB/s -7.6%
256KB Random Read 149.7 MB/s 207.3 MB/s +38.5%

As you'd expect, there's no real benefit to the new 6Gbps interface for random operations (particularly at low queue depths). Sequential speeds are much improved however. Xbench shows up to a 60% increase in performance in sequential operations.

You'll note that the absolute numbers are pretty low to begin with. A 128KB sequential read of the Intel SSD 510 on our desktop Sandy Bridge SSD testbed pulls nearly 400MB/s. On the new MacBook Pro we can't get more than 320MB/s.

Our sequential Iometer tests are run at a queue depth of 1 so there's no advantage there. The only explanation I can come up with (assuming Xbench's test is accurate) is that Apple may be aggressively implementing SATA controller power management under OS X. Capping the link's performance or aggressively putting it to sleep could reduce performance at the benefit of increasing battery life.

The other thing I noticed was that performance on the 13-inch MBP using Xbench was a bit lower than the 15-inch MBP. Take a look at these numbers:

SATA Performance—XBench 1.3
Intel SSD 510 250GB 13-inch 2011 MBP 15-inch 2011 MBP
4KB Sequential Write 155.3 MB/s 192.2 MB/s
256KB Sequential Write 184.8 MB/s 257.1 MB/s
4KB Sequential Read 30.4 MB/s 32.7 MB/s
256KB Sequential Read 201.8 MB/s 315.6 MB/s
4KB Random Write 49.6 MB/s 49.0 MB/s
256KB Random Write 183.9 MB/s 260.9 MB/s
4KB Random Read 13.9 MB/s 13.4 MB/s
256KB Random Read 144.9 MB/s 207.3 MB/s

I only noticed this with the Intel SSD 510, the Crucial RealSSD C300 and Vertex 3 both performed identically between the 13 and 15-inch MBPs. I'm not sure what's going on here at all, although I suspect that it's somehow related to the issues users have been having with some of these drives (more on this below).

SSD Recommendations

Where does all of this discussion about SSDs leave us? Unfortunately recommending an SSD for the new MacBook Pro today is pretty difficult but I'll try my best.

If you're the conservative type and just wants something that for sure works with little to no concern about absolute performance, the Apple SSDs are probably the safest bet. You'll get a drive that's much faster than a hard drive, fully supported by Apple and with TRIM support. Yes, that's right, OS X finally has TRIM support but Apple only enables it on it's own branded SSDs. To Apple's credit, given the number of problems I've seen with SSDs over the past couple of years it makes sense to lock down and only support drives you've validated. On the flip side however, Apple should be validating and working with controller makers to ensure all drives work under OS X. Making as much money as Apple does, I don't buy the "we didn't have the time/resources" argument.

If you are going down the Apple SSD path, at least the 128GB drive isn't super ridiculously priced, although I'm less comfortable recommending the 256GB version unless you can get it at $500.

Now if you want to get a faster SSD or actually take advantage of the 6Gbps interface, things get more complicated. I've heard reports of users having issues with the Intel SSD 510 and Crucial RealSSD C300. I've tested both drives as well as the OCZ Vertex 3 in three different MacBook Pros, and in all cases the drives worked perfectly. They were all detected as 6Gbps drives and all performed well. I should note that while I couldn't get the Vertex 3 Pro to work in the 2010 MacBook Pro, the Vertex 3 worked just fine in the 2011 MacBook Pro.

SATA Performance—XBench 1.3
13-inch 2011 MBP Crucial C300 256GB Intel SSD 510 250GB OCZ Vertex 3 240GB
4KB Sequential Write 239.0 MB/s 155.3 MB/s 319.9 MB/s
256KB Sequential Write 217.2 MB/s 184.8 MB/s 257.8 MB/s
4KB Sequential Read 35.1 MB/s 30.4 MB/s 33.3 MB/s
256KB Sequential Read 248.3 MB/s 201.8 MB/s 311.8 MB/s
4KB Random Write 175.0 MB/s 49.6 MB/s 247.8 MB/s
256KB Random Write 226.6 MB/s 183.9 MB/s 290.0 MB/s
4KB Random Read 19.1 MB/s 13.9 MB/s 21.1 MB/s
256KB Random Read 239.0 MB/s 144.9 MB/s 304.0 MB/s

SATA Performance—XBench 1.3
15-inch 2011 MBP Crucial C300 256GB Intel SSD 510 250GB OCZ Vertex 3 240GB
4KB Sequential Write 239.3 MB/s 192.2 MB/s 316.5 MB/s
256KB Sequential Write 218.8 MB/s 257.1 MB/s 282.0 MB/s
4KB Sequential Read 34.8 MB/s 32.7 MB/s 34.2 MB/s
256KB Sequential Read 245.1 MB/s 315.6 MB/s 306.7 MB/s
4KB Random Write 160.5 MB/s 49.0 MB/s 240.5 MB/s
256KB Random Write 227.5 MB/s 260.9 MB/s 311.3 MB/s
4KB Random Read 18.7 MB/s 13.4 MB/s 20.9 MB/s
256KB Random Read 238.2 MB/s 207.3 MB/s 303 MB/s

The Vertex 3 is the fastest drive out of the aforementioned three, but its availability and firmware maturity are both unknowns at this point. If you have to buy today and are ok with the chance that the drive may not work (given other experiences online, although I haven't seen problems), Intel's SSD 510 is likely a good runner up (at least for the 15-inch, the C300 seems to perform better on the 13).

As far as the reports of incompatibilities with these drives are concerned, I'm not really sure what's going on. I've been hammering on all of the drives, putting the system to sleep/waking it up, and haven't encountered any failures or high latency IO operations (stuttering) yet. That's not to say that these problems won't appear over time (I'm currently doing long term testing to figure that out now), but just that I haven't seen them yet.

If you are having issues with the Intel SSD 510, Crucial RealSSD C300 or anything else please email me (link at the top of the page) the following information:

1) What are the full specs of your MBP? Any upgrades?

2) Tell me about your SSD. Is it new out of box? Have you done anything to the drive? What model, firmware revision, etc...

3) Describe the symptoms of the issue—beachballs, data corruption, etc...? What do you have to do create the issue?

4) Is the drive detected as a 6Gbps drive or a 3Gbps drive?

5) Take me through your drive installation procedure, did you just pop it in, partition and install OS X?

6) Any visible damage to the SATA flex cable when you installed the drive?

7) Have you tried exchanging the SSD or MBP? Any difference in behavior?

We haven't seen any issues on three different 2011 models that we've been testing here extensively with the Intel SSD 510, Crucial RealSSD C300, OCZ Vertex 3 and OCZ Vertex 2. I realize a number of you are having issues so the more details I can get the better.

Apple's SSD Strategy The GPU Comparison
Comments Locked


View All Comments

  • Primetime89 - Thursday, March 10, 2011 - link

    Why are there repeated graphs for the same settings/specs showing different results? Particularly the SC2 scores
  • Anand Lal Shimpi - Thursday, March 10, 2011 - link

    I will clarify on the page - those are actually two different SC2 benchmarks. One is our GPU test and one is our CPU test. They have different workloads.

    Take care,
  • gstrickler - Thursday, March 10, 2011 - link

    Why do you set the screens at 50% brightness for your battery life tests (light web browsing and flash web browsing)? Since different models of laptop have such different brightness ranges, shouldn't you set them to a standard brightness (e.g 100, 150, or 200 nits) for testing? Seems far more useful and fair than 50%, which may be under 100 nits on some machines and over 200 nits on another.
  • TMoney415 - Thursday, March 10, 2011 - link

    Hey Anand and Crew,

    Terrific review. I loved reading your commentary, especially the conclusion discussing the real world benefits of moving from 2 to 4 cores. Its practical insights like that really separate you guys from the rest of the tech sites.

    One question though... You guys mentioned in the review that "OS X finally has TRIM support but Apple only enables it on it's own branded SSDs." As an owner of a 2010 MBP with an Apple SSD I still don't see TRIM support enabled in the system profile. What gives? Is TRIM only enabled for the 2011 models?
  • Anand Lal Shimpi - Friday, March 11, 2011 - link

    The 2011s have a slightly newer version of OS X than everything else at this point:

    System Version: Mac OS X 10.6.6 (10J3210)
    Kernel Version: Darwin 10.7.1

    We may have to wait until OS X 10.6.7 to really find out if other Apple SSDs will enable TRIM support.

    Take care,
  • rwei - Thursday, March 10, 2011 - link

    I'm not sure that your advice on SSDs being the best upgrade possible is applicable to all users.

    I recently installed a Vertex 2 128GB on a newly built Phenom II system for my parents. My own system, an i5 laptop with a 7200rpm Seagate HDD, still feels nearly as fast in most use cases. Naturally the Vertex 2 is faster, but to put things in perspective:
    - Windows 7 boots in maybe 15s on the Vertex 2, vs. 25s on my laptop
    - Word takes 0.5s to load on the V2, 2-3s on my laptop
    - Loading multiplayer SC2 map takes 3s on the V2 vs 6-7s on my laptop
    - Installing programs on the V2 happens so fast I can't even click "cancel"

    In all cases here we're talking a 2-10x speed increase, which seems nice. But realistically, if you aren't doing the things that Anand typically does (install a crapload of programs, load a crapload a programs, benchmark the crap out of a crapload of programs) you spend very little time actually doing any of the things that an SSD offers a speed boost to. In all, I might save 50-100s/day using an SSD vs. my HDD.

    Meanwhile, I have 4x the storage on my laptop, for 1/3 of the cost, and comparable power consumption (though the heat from the HDD is a pain in the butt).

    Especially on a machine with plenty of RAM, or at least enough to make good use of ReadyBoost, having an SSD really isn't the magic sauce that you consistently make it out to be, at least for an average user. I especially disagree with your point that a 7200RPM drive is not an important upgrade. It's a HUGE difference over a 5400RPM one, and especially the cheap kind that often come with laptops.
  • Chloiber - Friday, March 11, 2011 - link

    I do agree.

    I am using SSDs since "the Beginning" (4 years or so) and can't think of using anything else in my Desktop or my older laptop with a slow 5400rpm HDD. The difference is huge.
    But in my ThinkPad, the 7200rpm 2.5" HDD actually isn't that bad. Things load quickly after the initial boot (using Standby or Hibernation anyway) - I never have the feeling "Ah damn HDD, so slow!".
    I never thought I'd say this: but I don't need an SSD in my Notebook for Speed.

    BUT - and here it comes - I WANT one because a 7200rpm HDD is loud and heats up. The Notebook would be completely silent without the HDD...
    In addition, as soon as I get my Docking Station, I really want superb speed when using this thing as a desktop computer, and not just "good" speed...

    You don't need one, if you have a speedy HDD, but it certainly doesn't hurt and it still is probably the best upgrade you can make.
  • tno - Friday, March 11, 2011 - link

    Take a look at the SSD page again and look at Anand's graph on multiple applications opening.

    The typical user (and let's go ahead and define that set as almost everyone that has never heard of AT) installs whatever virus software came with their computer (no matter how bulky and slow), along with willingly installing "update" software provided by PC manufacturers that generally consists of a background task that pings various update servers all day long, downloads endless numbers of toolbars and wallpaper applications, and wants to open up their favorite browser (IE7) so they can load up all their favorite websites (Facebook) the moment they turn their computer on. But with tons of background tasks loading along with the OS, the wait to load up IE7 can seem interminable, with the user sitting at a seemingly fully loaded desktop, clicking the same icon over and over again.

    This is the classic "slow-down" scenario that Geek Squad promises to remedy with it's "tune-up" service that if Consumerist is right involves stealing all your porn, replacing it with other porn and then emptying your Recycle Bin. And going from a 5400RPM drive to a 7200RPM drive will not make a whole lot of difference in these multiple programs loading scenarios because it's the average Random Seek Time which makes this take forever and that value will be fairly equal in each drive.

    Swapping in an SSD, even a slower one, can make this process painless. So while you're right, you don't save that much time booting Windows, opening Word, installing a program. You do save tons of time doing all those things at once.

    Oh, and ReadyBoost (http://en.wikipedia.org/wiki/ReadyBoost) doesn't load to RAM it loads to any flash devices attached to the computer.
  • zhill - Friday, March 11, 2011 - link

    I agree that with a reasonable reserve of RAM the OS should be caching your frequently use files, so the 2nd time you open Word etc, it should be fairly quick, but the problem with saying SSD isn't worth it is that regardless of CPU and RAM, HDD performance is basically static and has been for several years. You can spend $2K on a superfast CPU but it will just be waiting on the disk all the time. But, I do agree that boot-time specs aren't all that important because how often do you actually cold-boot your machine in a given day anyway? Once? Twice? A decent HDD versus the crap in most PCs does make a difference (the cache and the RPM), so point well taken.

    That said, if all you do is gaming and web-browsing then the gains of SSDs aren't all that important other than levels loading faster etc. But if you do much content creation (Photoshop, video, etc) then it's a huge bonus because you can keep that CPU and RAM fed. The MB Air is a perfect example of how SSDs make marginal CPUs more usable. This is Amdahl's Law in action, speed up the slowest part of your system for the biggest gains.
  • khimera2000 - Friday, March 11, 2011 - link

    then you move over to notebooks. the advantages...

    HEAT in a place thats really confined having less heat comming of one item contrebutes to the life of the machine :D

    POWER an SSD uses less power... that simple.

    SInce where talking about a MBP I would agree with the author. an SSD is a good upgrade no matter who you are be it for power heat or perfromance. when moving to a desktop though the SSD thing becomes harder to justify. At that point I would weigh out pros VS cons of using a SSD vs HDD on a desktop.

Log in

Don't have an account? Sign up now