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SSD and USB flash benchmarks
 


2016-10-03 at 00:09 #6517   (1)
I thought folks might be interested in these benchmarks I've done on SSDs and USB flash sticks I bought from Amazon. I ran Blackmagic Disk Speed Test, and these are the numbers on the dials at the top. I used my 13" MacBook Pro to do the tests, which are not ultra-scientific nor super-precise but should be good enough to get a decent overview of the options.

The mSATA SSDs were installed in Sabrent mSATA USB3 enclosures, which are tiny and fast. The MX300 was tested using a Sabrent SATA-USB3 cable adapter. The MX200 and M500 are installed inside MacBook Pros.

Note that performance can vary a lot between different-sized versions of the same SSD - for example, a 256GB MX100 might be slower than a 512GB MX100, or an mSATA version might be slower than a 2.5-inch SATA version.

Write   Read  (MB/sec.)

  13      90    Kingston K32GB DTMicro
  20      98    Transcend 32GB JetFlash 710
  23    149    Samsung 32GB BAR
  37      40    ADATA S102 Pro 64 GB
  86     134   Kingston 64GB DataTraveler
112     244   Patriot 32GB Supersonic Rage

287     424   Crucial MX200 250GB mSATA
295     432   Samsung 850 EVO 250GB mSATA
382     430   Samsung 850 EVO 1TB mSATA
423     376   Crucial MX300 525GB SATA 2.5" **See follow-up below...

311     463   Crucial M500 960GB SATA 2.5" (2011 MacBook Pro 13")
458     501   Crucial MX200 1TB SATA 2.5" (2012 MacBook Pro 13")


2016-10-03 at 02:51 #6519   (2)
The fastest flash drive I've used is the SanDisk Extreme.


2016-10-03 at 09:37 #6521   (3)
(2016-10-03 at 00:09)Ric Ford wrote:    37      40    ADATA S102 Pro 64 GB
I would avoid the ADATA models as (a former AMT), there was issue after the 101 models in that it would not boot later generation MacBook Pro models. Lately, the metal Kingston USB3.0 DT models have been much faster than anything in price and size (metal with hole for keyring). The largest size USB 3.0 I have is the Sandisk Extreme Pro 128GB... seems I transition every 3-4 years to larger flash drives.


2016-10-03 at 10:43 #6529   (4)
I bought a few of these
Sandisk CZ600 Cruzer Glide™ 256 GB USB 3.0 Flash Drive
http://www.costco.com/Sandisk-CZ600-Cruz...90584.html

and tried the Blackmagic speed test.

I had 44.1 Write and 97.1 Read speeds.

I use one as a bootable backup of my internal 256GB SSD -- a bit slow, but it does boot and work -- and a second one for a dupe of daily files.


2016-10-03 at 11:42 #6533   (5)
Hi Ric,

I have found this site useful for SSD benchmarks.

http://www.harddrivebenchmark.net

It seems to be updated on a regular basis.

Thanks for running the best Mac site on the web!


2016-10-03 at 15:27 #6549   (6)
(2016-10-03 at 00:09)Ric Ford wrote:  The MX300 was tested using a Sabrent SATA-USB3 cable adapter.
...
Write   Read  (MB/sec.)

423     376   Crucial MX300 525GB SATA 2.5" **See follow-up below...
These numbers looked odd, and I was also having some problems with the SSD dropping off the USB bus unexpectedly (though it passed a tough SoftRAID certification test). So I did some follow-up testing, switching the MX300 from the Sabrent USB adapter to a Newer Tech Voyager S3 USB 3 drive dock.

My first re-test showed a 10x drop in performance... Oops! I'd used a USB 2 cable. Switched to a blue USB 3 cable and re-ran Blackmagic's benchmark program. As I've often seen before, repeated tests show some inconsistency and sometimes a slowdown over time, but initial tests are now showing the following with the Voyager S3 dock:

Write   Read  (MB/sec.)

397     505   Crucial MX300 525GB SATA 2.5" (USB 3 dock)


michaelg Show this Post
2016-10-04 at 00:08 #6587   (7)
michaelg
Using Blackmagic Speed Test -- you don't specify what size file you are using. As I now see two different people comparing hard numbers I wonder if the comparison is valid.


2016-10-04 at 00:20 #6590   (8)
(2016-10-04 at 00:08)michaelg wrote:  Using Blackmagic Speed Test -- you don't specify what size file you are using. As I now see two different people comparing hard numbers I wonder if the comparison is valid.
Sorry, I used the 5GB default.

Also, I should note that you have to click the gear widget and then select which target drive you want to test.


2016-10-04 at 11:32 #6636   (9)
Kingston HyperX Savage 128 GB USB Stick USB 3.1 gen 1
Advertised speed: "up to" 250 MB/s write and up to 350 MB/s read.

Blackmagic Disk Speed Test used, average of several tests:

Write: about 240 MB/s (high of about 245 MB/s - low about 180 MB/s)
Read: 380 MB/s (high of about 385, low about 370 at times, typically closer to 380)

The write speeds varied much more than the reads with this test.

In actual usage doing large video copies, I have had the OS reporting up to 300 MB/s for a sustained 22GB transfer to the stick. (Took just over a minute to copy - the math would have that work out to about 75 seconds at that sustained speed; at 250 MB/s it would be 90 seconds and it didn't take that long.)

With small file transfers, there is, for sure, an overhead for file creation, like most USB sticks - with over 5000 small files, the copy speed was under 1 MB/s.


2016-10-06 at 13:35 #6800   (10)
Couldn't resist buying one of these and testing it with the Blackmagic utility. The device is wide, heavy and solid device with a blue activity light and a removable cap that has a rubbery interior (so maybe it helps seal against moisture?).

Write   Read  (MB/sec.)
 145     369    Corsair Flash Voyager GTX 128GB


2016-10-06 at 13:54 #6802   (11)
Just used SMART Utility (with SAT SMART Driver) to check status for a few USB flash drives (quite different from hard drives):

Samsung BAR 32GB:
  "Failed"
SMART Utility shows ten reallocated bad sectors and "Failing" for Unknown Attributes 101 and 23.
I've used this flash drive for a few things (e.g. trying Linux Live USBs, performance tests) but not heavily. Its form factor is my favorite, although it's not very fast. It looks like these Unknown Attribute failures may not be correct, however. I just ran a SoftRAID Certify operation on the drive and it's not showing any errors. The SMART attributes don't seem to have changed during the Certify operation.

Corsair Flash Voyager GTX 128GB:
  Passed
(Attributes 101 and 23 are not listed, but it shows a number of attributes that the Samsung device doesn't.)

Kingston 64GB DataTraveler:
  Not Supported

Patriot Rage XT 32GB
  Not Supported


2016-10-07 at 00:15 #6839   (12)
Guest
Makes me want to grab all my various USB Flash Drives to benchmark and test for viability.

Is there any consensus with the readers here at MacInTouch as to the need or a preference for either SMART Utility or one of the SMARTReporter/SSDReporter products? SMART Utility runs $25 at the moment while the full SMARTReporter is only $5.99. Is SMART Utility that much more comprehensive in what it does and reports? Is there another product we should also consider?

I also saw where SMART Utility will have a new version 4.0 available in "the fall."

https://www.volitans-software.com/2016/0...ouncement/

Version 4.0 will be released in approximately six months. Pricing has not been set for version 4.0, but it is only fair to announce ahead of time that the the update will not be free. However, any purchase after today (May 1st, 2016) will not be charged an update fee.


2016-10-11 at 15:50 #7080   (13)
I just tested SanDisk Extreme Pro and SanDisk Extreme SD cards and have now updated this list of flash and SSD results from Blackmagic Design Disk Speed Test:

Write   Read  (MB/sec.)

SD card (2012 MacBook Pro SD slot):
  43      86   SanDisk Extreme 16GB
  68      89   SanDisk Extreme Pro 32GB

USB3 flash drive:
  13      90    Kingston K32GB DTMicro
  20      98    Transcend 32GB JetFlash 710
  23    149    Samsung 32GB BAR
  37      40    ADATA S102 Pro 64 GB
  86     134   Kingston 64GB DataTraveler
112     244   Patriot 32GB Supersonic Rage
145     369   Corsair Flash Voyager GTX 128GB

SSD via USB3-SATA adapter:
287     424   Crucial MX200 250GB mSATA
295     432   Samsung 850 EVO 250GB mSATA
382     430   Samsung 850 EVO 1TB mSATA
397     505   Crucial MX300 525GB SATA 2.5"

SSD via internal SATA:
311     463   Crucial M500 960GB SATA 2.5" (2011 MacBook Pro 13")
458     501   Crucial MX200 1TB SATA 2.5" (2012 MacBook Pro 13")


2016-10-12 at 04:15 #7100   (14)
I don't see any SanDisk flash drives. The Extreme is very fast.


2016-10-12 at 09:46 #7108   (15)
(2016-10-11 at 15:50)Ric Ford wrote:  I just tested SanDisk Extreme Pro and SanDisk Extreme SD cards and have now updated this list of flash and SSD results from Blackmagicdesign Disk Speed Test ...
Thanks for that, Ric. And that concludes my stance on using an SD as a boot drive (we tried as ACMTs to use repair/test tools when the USB ports were damaged) is painfully s l o w.


2016-10-12 at 18:06 #7145   (16)
(2016-10-11 at 15:50)Ric Ford wrote:  I just tested SanDisk Extreme Pro and SanDisk Extreme SD cards and have now updated this list
Ric,

Did you happen to try any of the SD cards via a USB card reader and in a USB 2 port or the USB flash drives via USB 2? I suppose that might be tough to do on the 2012, but easy on the 2011 MacBook Pro, if you have the same testing software installed.

Thanks,
Dave


2016-10-12 at 18:57 #7147   (17)
(2016-10-12 at 18:06)Dave G wrote:  Did you happen to try any of the SD cards via a USB card reader and in a USB 2 port or the USB flash drives via USB 2? I suppose that might be tough to do on the 2012, but easy on the 2011 MacBook Pro, if you have the same testing software installed.
I haven't tried a USB SD card reader at all, so far.


2016-12-19 at 19:56 #11565   (18)
(2016-10-03 at 00:09)Ric Ford wrote:  I thought folks might be interested in these benchmarks I've done on SSDs and USB flash sticks I bought from Amazon. I ran Blackmagic Disk Speed Test, and these are the numbers on the dials at the top. I used my 13" MacBook Pro to do the tests, which are not ultra-scientific nor super-precise but should be good enough to get a decent overview of the options.

The mSATA SSDs were installed in Sabrent mSATA USB3 enclosures, which are tiny and fast. The MX300 was tested using a Sabrent SATA-USB3 cable adapter. The MX200 and M500 were installed inside MacBook Pros.

Note that performance can vary a lot between different-sized versions of the same SSD - for example, a 256GB MX100 might be slower than a 512GB MX100, or an mSATA version might be slower than a 2.5-inch SATA version.
Here's an updated set of benchmarks using BlackMagic Design Disk Speed Test (5GB file size). I tested a Samsung 2TB EVO 850 2.5" SATA SSD inside a 2012 MacBook Pro 13" and in a Neutrino U3+ enclosure connected via USB 3.0.

Write Read (MB/sec.)

SD card (2012 MacBook Pro SD slot):
  43   86 SanDisk Extreme 16GB
  68   89 SanDisk Extreme Pro 32GB

USB3 flash drive:
  13   90 Kingston K32GB DTMicro
  20   98 Transcend 32GB JetFlash 710
  23 149 Samsung 32GB BAR
  37   40 ADATA S102 Pro 64 GB
  86  134 Kingston 64GB DataTraveler
112  244 Patriot 32GB Supersonic Rage
145  369 Corsair Flash Voyager GTX 128GB

SSD via USB 3.0 SATA adapter/enclosure:
287   424 Crucial MX200 250GB mSATA
423   376 Crucial MX300 525GB SATA 2.5"
295   432 Samsung 850 EVO 250GB mSATA
382   430 Samsung 850 EVO 1TB mSATA
382   401 Samsung 850 EVO 2TB SATA 2.5"

SSD via internal SATA:
311   463 Crucial M500 960GB SATA 2.5" (2011 MacBook Pro 13")
458   501 Crucial MX200 1TB SATA 2.5" (2012 MacBook Pro 13")
484   502 Samsung 850 EVO 2TB SATA 2.5" (2012 MacBook Pro 13")


2016-12-20 at 13:12 #11599   (19)
372   423   Samsung T3 1TB (via USB 3 direct to MacBook Pro 15", Late 2013)
368   422   Samsung T3 500GB (via USB 3 direct to MacBook Pro 15", Late 2013)


2016-12-20 at 19:11 #11632   (20)
(2016-12-19 at 19:56)Ric Ford wrote:  SSD via USB 3.0 SATA adapter/enclosure:
287   424 Crucial MX200 250GB mSATA
423   376 Crucial MX300 525GB SATA 2.5"
295   432 Samsung 850 EVO 250GB mSATA
382   430 Samsung 850 EVO 1TB mSATA
382   401 Samsung 850 EVO 2TB SATA 2.5"

SSD via internal SATA:
311   463 Crucial M500 960GB SATA 2.5" (2011 MacBook Pro 13")
458   501 Crucial MX200 1TB SATA 2.5" (2012 MacBook Pro 13")
484   502 Samsung 850 EVO 2TB SATA 2.5" (2012 MacBook Pro 13")
Thanks for doing that testing. It's nice to see how fast the SSDs are via USB 3.0 compared to the internal SATA. Very usable via USB 3.0.


2016-12-21 at 00:27 #11659   (21)
(2016-10-03 at 00:09)Ric Ford wrote:  I thought folks might be interested in these benchmarks I've done on SSDs and USB flash sticks I bought from Amazon. I ran Blackmagic Disk Speed Test (5GB test size), and these are the numbers on the dials at the top. I used my 13" MacBook Pro to do the tests, which are not ultra-scientific nor super-precise but should be good enough to get a decent overview of the options.

The mSATA SSDs were installed in Sabrent mSATA USB3 enclosures, which are tiny and fast. The MX300 was tested using a Sabrent SATA-USB3 cable adapter. The MX200 and M500 were installed inside MacBook Pros.

Note that performance can vary a lot between different-sized versions of the same SSD - for example, a 256GB MX100 might be slower than a 512GB MX100, or an mSATA version might be slower than a 2.5-inch SATA version.
N.B. I forgot to note earlier that some of the SSD tests are for FileVault 2 encrypted drives. I haven't done comparisons between unencrypted and encrypted volumes.

Here's an updated set of benchmarks that adds the 64GB version of the Samsung Bar (great form factor, quirky speed variation), the MX200 in a Neutrino U3+ (USB3) enclosure, and the Samsung T3 tests from EricSM:

Write  Read    (MB/sec.)

SD card (2012 MacBook Pro SD slot):
  43   86   SanDisk Extreme 16GB
  68   89   SanDisk Extreme Pro 32GB

USB3 flash drive:
  37   40    ADATA S102 Pro 64 GB
  13   90    Kingston K32GB DTMicro
  20   98    Transcend 32GB JetFlash 710
  23 149    Samsung 32GB BAR
  35 149    Samsung 64GB BAR (write speed inconsistent)
  86 134    Kingston 64GB DataTraveler
112 244    Patriot 32GB Supersonic Rage

USB3 SSD:
145  369   Corsair Flash Voyager GTX 128GB
372  423   Samsung T3 1TB (via USB 3 direct to MacBook Pro 15", Late 2013)
368  422   Samsung T3 500GB (via USB 3 direct to MacBook Pro 15", Late 2013)

SSD via USB 3.0 SATA adapter/enclosure:
287   424   Crucial MX200 250GB mSATA
381   399   Crucial MX200 1TB SATA 2.5" (FileVault2)
423   376   Crucial MX300 525GB SATA 2.5"
295   432   Samsung 850 EVO 250GB mSATA
382   430   Samsung 850 EVO 1TB mSATA
382   401   Samsung 850 EVO 2TB SATA 2.5"

SSD internal SATA:
311   463   Crucial M500 960GB SATA 2.5" (2011 MacBook Pro 13")
458   501   Crucial MX200 1TB SATA 2.5" (2012 MacBook Pro 13")
484   502   Samsung 850 EVO 2TB SATA 2.5" (2012 MacBook Pro 13")


Jerry J Show this Post
2016-12-21 at 01:22 #11664   (22)
Jerry J
(2016-12-21 at 00:27)Ric Ford wrote:  Here's an updated set of benchmarks ...
Very interesting! Thanks all y'all.

I haven't been keeping up - is it still true that TRIM doesn't work via any USB connection?


2016-12-21 at 01:25 #11665   (23)
(2016-12-21 at 01:22)Jerry J wrote:  I haven't been keeping up - is it still true that TRIM doesn't work via any USB connection?
Interestingly, Angelbird's pricy SSD2go USB 3 storage device does support TRIM (via special driver software), but is the only such product to do so, as far as I know.


2016-12-21 at 16:04 #11710   (24)
(2016-12-21 at 00:27)Ric Ford wrote:  Here's an updated set of benchmarks ...
For what it's worth, here are the results of running the same test on the internal 500-GByte SATA SSD in my 2014 Retina 5K iMac (identified by System Information as APPLE SSD SM0512F) running 10.12.2:

Write: 689 MByte/s Read: 716 Mbyte/s

And for the internal 251-Gbyte SATA SSD in a 2013 MacBook Air (APPLE SSD SM0256F) also running 10.12.2:

Write: 326 Mbyte/s Read: 694 Mbyte/s


2016-12-21 at 16:18 #11712   (25)
(2016-12-21 at 01:25)Ric Ford wrote:  Interestingly, Angelbird's pricy SSD2go USB 3 storage device does support TRIM (via special driver software), but is the only such product to do so, as far as I know.
Many of StarTech.com's newer USB enclosures claim to support TRIM. For example:

StarTech wrote:https://www.startech.com/HDD/Enclosures/...251BPU31C3
Does this device support the TRIM command?
Yes, this device supports the TRIM command. If the OS issues a TRIM command, the command will be passed to the connected device.
I've ordered one of their USB enclosures for an M.2 SSD but have not used any of their enclosures as of yet.

Can anyone verify TRIM is in effect with one of the new StarTech.com USB enclosures? How does one actually verify this for a USB-attached SSD?


2016-12-21 at 17:45 #11719   (26)
(2016-12-21 at 16:04)Joe Gurman wrote:  For what it's worth, here are the results of running the same test on the internal 500-GByte SATA SSD in my 2014 Retina 5K iMac (identified by System Information as APPLE SSD SM0512F) running 10.12.2:

Write: 689 MByte/s Read: 716 Mbyte/s
That's more likely an Apple-proprietary PCIe SSD, not a SATA SSD, isn't it?

(Cf. https://www.ifixit.com/Teardown/iMac+Int...down/30260)

(2016-12-21 at 16:04)Joe Gurman wrote:  And for the internal 251-Gbyte SATA SSD in a 2013 MacBook Air (APPLE SSD SM0256F) also running 10.12.2:

Write: 326 Mbyte/s Read: 694 Mbyte/s
Ditto for the MacBook Air.

(I don't think SATA, at 6Gbps max, supports the speeds you're seeing there.)


2016-12-21 at 20:40 #11738   (27)
(2016-12-21 at 16:18)eric wrote:  Can anyone verify TRIM is in effect with one of the new StarTech.com USB enclosures? How does one actually verify this for a USB-attached SSD?
The way I've seen it done on Linux systems is:
  • Write a file to the drive. To keep it simple, make it small enough to fit in a single logical block (less than 512 bytes). Read its contents to confirm that it was written.
  • Use some kind of raw disk-access utility to record the logical blocks that hold the file's contents.
  • Read those blocks and confirm that you are reading the file's data.
  • Delete the file. Use the command-line "rm" command. If you use the Finder, be sure to empty the Trash. Make sure there is no kind of "secure empty trash" taking place.
  • Go back and read the file's blocks. If you see zeros then TRIM is definitely working. If you see the original contents from the deleted file, then TRIM might not be working. (But it might - some drives don't return zeros for a block that is marked garbage but has not yet been collected.)
Of course, even easier than working out the appropriate Mac tools for this is you could just get System Information and look at the volumes on the Storage panel. Each volume that is using TRIM should be indicated as such in the report.


2016-12-22 at 08:00 #11766   (28)
(2016-12-21 at 01:25)Ric Ford wrote:  Interestingly, Angelbird's pricy SSD2go USB 3 storage device does support TRIM (via special driver software), but is the only such product to do so, as far as I know.
(2016-12-21 at 16:18)eric wrote:  Many of StarTech.com's newer USB enclosures claim to support TRIM. For example:

StarTech wrote:https://www.startech.com/HDD/Enclosures/...251BPU31C3
Does this device support the TRIM command?
Yes, this device supports the TRIM command. If the OS issues a TRIM command, the command will be passed to the connected device.
I've ordered one of their USB enclosures for an M.2 SSD but have not used any of their enclosures as of yet. Can anyone verify TRIM is in effect with one of the new StarTech.com USB enclosures? How does one actually verify this for a USB-attached SSD?
I have one of the StarTech USB 3.1 (10Gbps) Tool-Free Enclosures with a Samsung EVO PRO 850 SSD in it (that used to be in my old MacBook Pro 2011 model) connecting it over USB-C to my new MacBook Pro 2016 TouchBar model and using it as a backup drive. When it's plugged in, System Information > Storage simply reports the drive as "Protocol: USB" and there is no mention of TRIM. Mind you, when I check the built-in MacBook storage, that doesn't even mention TRIM either. In addition, Disk Utility > Info reports nothing useful.   :-(

Clearly, there's (currently) no easy way on standard macOS to see whether TRIM is supported on an external (USB) drive.


2016-12-22 at 11:32 #11771   (29)
(2016-12-22 at 08:00)MacStrategy wrote:  I have one of the StarTech USB 3.1 (10Gbps) Tool-Free Enclosures with a Samsung EVO PRO 850 SSD in it (that used to be in my old MacBook Pro 2011 model) connecting it over USB-C to my new MacBook Pro 2016 TouchBar model and using it as a backup drive. When it's plugged in, System Information > Storage simply reports the drive as "Protocol: USB" and there is no mention of TRIM. Mind you, when I check the built in MacBook storage that doesn't even mention TRIM either. In addition, Disk Utility > Info reports nothing useful  :-(
With OS X 10.11, for an internal SATA SSD, you have to go to About This Mac > System Report... > Hardware > SATA/SATA Express > Samsung SSD 850 EVO   and I see:

...
Medium Type: Solid State
TRIM Support: Yes
Partition Map Type: GPT (GUID Partition Table)
S.M.A.R.T. status: Verified
...
This terminal command may be easier:

system_profiler SPSerialATADataType | grep 'TRIM'
If I go to About This Mac > System Report... > Hardware > USB > Neutrino U3+  I see:

...
Detachable Drive: Yes
BSD Name: disk4
Partition Map Type: GPT (GUID Partition Table)
S.M.A.R.T. status: Verified
with no mention of Trim.

Typing:

system_profiler | grep 'TRIM'
produces the same result as the previous command, listing Trim support for the internal SATA SSD:

TRIM Support: Yes


2016-12-22 at 15:23 #11796   (30)
I don't see any of my USB-attached SATA SSDs listed under Hardware > SATA/SATA Express. They are only listed under Hardware > USB. Of course currently they do not list a TRIM line item, but I'm not yet using either a new StarTech or Angelbird enclosure.

Thanks for any additional suggestions you have!


2016-12-23 at 04:44 #11838   (31)
(2016-12-22 at 11:32)Ric Ford wrote:  With OS X 10.11, for an internal SATA SSD, you have to go to About This Mac > System Report... > Hardware > SATA/SATA Express > Samsung SSD 850 EVO   and I see:

...
  Medium Type:    Solid State
  TRIM Support:    Yes
  Partition Map Type:    GPT (GUID Partition Table)
  S.M.A.R.T. status:    Verified
...
This terminal command may be easier:

system_profiler SPSerialATADataType | grep 'TRIM'
As per Eric above, nothing appears under About This Mac > System Report... > Hardware > SATA/SATA Express - not even the built-in storage. That now appears under NVMExpress - where I notice TRIM is indeed listed as supported (thankfully).

The external SSD appears under Storage, where TRIM is not listed. I believe Apple has to support TRIM over USB through their USBIOMassStorage drivers within macOS (but they don't at the moment) - there's a similar thread to ours here:

  https://www.cindori.org/forums/topic/ext...itan-trim/


2017-01-18 at 16:13 #13403   (32)
I just noticed this passage about SSD performance at the end of the Blackmagic Disk Speed Test manual (available via Disk Speed Test help within the app):

Blackmagic Design wrote:Important note about Solid State Disk (SSD) speeds

Some models of SSD cannot save video data at the speed indicated by the manufacturer because the disk uses hidden data compression to reach these higher write speeds. This data compression technique can only save data at the manufacturer’s claimed speed when storing simple files or simple data, such as blank data. Video data includes video noise, and more random pixel data which does not compress much, so the true speed of the disk is seen.

Some SSD’s can have up to 50% lower write speed than the manufacturer’s claimed speed, so even though the disk specifications claim an SSD is fast enough to handle video, in reality the disk is not fast enough for real time video data capture. Hidden data compression mostly affects capture and often these disks can still be used for real time playback.

Use Blackmagic Disk Speed Test to measure accurately if your SSD will be able to handle uncompressed video capture and playback. Blackmagic Disk Speed Test uses data to simulate the storage of video so you get results similar to what you will see when capturing video to a disk. This will let you find models of SSD that work well for video capture. In our testing, we have found larger newer models of SSD, and larger capacity SSD’s are generally faster. Blackmagic Disk Speed Test also tests the speed of disks connected to eSATA docks and other interfaces, which can affect disk performance.


2017-01-19 at 11:36 #13450   (33)
I was disappointed to see Ric's post about how some manufacturer's claimed SSD write performance specs depend on data compression built into the SSD hardware. In my opinion, that's cheating, even if the manufacturer includes average data compressibility assumptions in the fine print. Advertisements and packaging should clearly state raw performance with non-compressible data. Manufacturers could achieve astonishing data rates if they write only files filled with zeros.


2017-01-19 at 15:10 #13474   (34)
(2017-01-18 at 16:13)Blackmagic Design wrote:  Important note about Solid State Disk (SSD) speeds

Some models of SSD cannot save video data at the speed indicated by the manufacturer because the disk uses hidden data compression to reach these higher write speeds.
This has been a well-known issue since the appearance of the SandForce SSD controller, which employs compression, several years ago. Not only can most video files not be further compressed, but neither can jpegs or much of the OS X system, which itself makes extensive use of compressed files.

I've always avoided SSD's that rely on compression, and see no reason to change that.


2017-02-19 at 16:09 #15412   (35)
Somewhat related to this thread, I'm looking for an external boot drive for a MacBook Air 11" early 2015.
I want a fast SSD, but only Thunderbolt or USB 3.x. Nothing in an external enclosure. Preferred capacity 512 GB to 1TB - 256GB, maybe. This needs to be very good speed as a boot drive. I intend to use it only when doing iTunes updates to store the large app files and preserve space on the internal 128GB SSD.

I have tried other flash drives and found them glacial when used as a boot drive.

From this thread, I see benchmarks for
USB3 SSD:
   145 369 Corsair Flash Voyager GTX 128GB
   372 423 Samsung T3 1TB (via USB 3 direct to MacBook Pro 15", Late 2013)
   368 422 Samsung T3 500GB (via USB 3 direct to MacBook Pro 15", Late 2013)

The Samsung specs look good, but Amazon reviews show problems with Macs, at least the encryption s/w. I don't need encryption. Will it work without it and how well? If performance justifies, I'll then have to put aside my disgust for Samscum's business model and total lack of ethics.

The Corsair also has a 256GB model, which would be my bare minimum.

Any other suggestions/experiences for my need? Thanks in advance. I apologize if this has been covered elsewhere. One problem with having too much information!   ;-)


2017-02-19 at 16:15 #15414   (36)
I did have a friend purchase this Transcend Thunderbolt drive for file transfers and storage. Haven't tried it as a boot drive. Any experiences/ benchmarks?
   Transcend 512GB Thunderbolt Solid State Drive StoreJet 500 for Mac


2017-02-19 at 19:37 #15423   (37)
(2017-02-19 at 16:15)Gene_L wrote:  I did have a friend purchase this Transcend Thunderbolt drive for file transfers and storage. Haven't tried it as a boot drive. Any experiences/ benchmarks?
   Transcend 512GB Thunderbolt Solid State Drive StoreJet 500 for Mac
The Amazon description shows "read and write speeds of up to 440MB and 300MB per second", which is decent for USB 3. I'll respond below to your other note about options.


2017-02-19 at 19:42 #15424   (38)
(2017-02-19 at 16:09)Gene_L wrote:  I'm looking for an external boot drive ... Nothing in an external enclosure.
I'm a little confused about what you want here... If it's an external drive, you'll need an external enclosure, although there is also this option:

  Sabrent USB 3.1 (Type-A) to SSD / 2.5-Inch SATA Hard Drive Adapter

which I've used a lot myself. It's both inexpensive and fast. (And there's no enclosure!) Plug in any standard SATA SSD, and you're good to go at full USB 3 speed. The only downside is a lack of support for Trim (which might work with a Thunderbolt drive).

If you do actually want an enclosure, I'm fond of these, which are also fast:

  Neutrino U3+ / UASP (enclosure only) (with FireWire 800 and USB 3)
  Neutrino U3 w/ UASP (Enclosure Only) (USB 3 only)

You can see the benchmarks above under "SSD via USB 3.0 SATA adapter/enclosure."


2017-02-19 at 19:53 #15425   (39)
(2017-02-19 at 19:37)Ric Ford wrote:  The Amazon description shows "read and write speeds of up to 440MB and 300MB per second"...
I think that's for the USB 3 interface? Wouldn't the Thunderbolt 2 rates be much faster?
The MacBook Air has a Thunderbolt 2 port.


2017-02-19 at 19:59 #15428   (40)
(2017-02-19 at 19:53)Gene_L wrote:  I think that's for the USB 3 interface? Wouldn't the Thunderbolt 2 rates be much faster?
If you're using an SSD with a SATA interface (which is the norm), you're limited by SATA to 6Gbps. USB 3.0 is limited to 5Gbps, which is pretty close, and you may not see much difference (if any) between Thunderbolt 2 and USB 3 if you're not using unusual SSD setups, such as a RAID array or NVMe/PCI-based flash.

(You can find lots of SSD products with a search on "SSD" in the MacInTouch Recent News and Older News pages.)