Sidebar Sidebar
Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

Running OSX of USB 3.0

S

sui.page

macrumors member
Original poster
May 13, 2012
38
0
I've been sussing out solid options for a new mac mini setup and initially thought upgrading to a SSD drive would be my only option. Then I saw how many USB 3.0 ports there were and thought what if I could make the most of those ports.

So my question is would it be possible to run OSX and all my applications off a single 128GB USB 3.0 thumb drive? This way I could even have a setup where I have 256GB(two 128GB USBs) of flash memory plus the 500GB HDD stock storage. This might even be cheaper than buying a single SSD drive. Then on top of that I'd have the flexibility of carrying around my data on those USBs if I needed. That would be a dream!

If this is a possibility what would the speed differences be like between the SATA connector to a SSD vs the USB 3.0 setup I've just outlined?
 
Last edited:
Interesting. I think it would work, but not sure about speed or reliability. Thumb drive would not have wear leveling, garbage collection, TRIM, etc., capabilities of SSD. SSD in USB 3 enclosure works fine.
 
niteflyr said:
Interesting. I think it would work, but not sure about speed or reliability. Thumb drive would not have wear leveling, garbage collection, TRIM, etc., capabilities of SSD. SSD in USB 3 enclosure works fine.
Click to expand...

Looks like there a lot of things to account for, I don't know all these tech terms you're throwing at me but thanks for the input. Dang it looks like it might not be easy straightforward as I thought.

Btw would you know how to delete threads as I've accidentally doubled up.
 
For Garbage Collection (GC) and wear leveling check out the following article: https://en.wikipedia.org/wiki/Garbage_collection_(SSD)#Garbage_collection

Basically you want TRIM/GC because it clears out NAND cells in order to keep the performance of the ssd as close to when it came out of the factory (when you fill up the cells the performance deteriorates greatly; this also means that you shouldn't be filling up the entire drive with data). This somewhat applies to ordinary disks (hdd) too (fill them up and they become slower).

USB3 thumbdrives have a speed of max 80~100MB/s in real life. SSD's go beyond that (300~400 MB/s). USB3 offers a theoretical speed of up to 5Gbps which means that an SSD is able to get the most out of it, thumbdrives won't because they are not that fast. When compared to SATA there will be some speed loss but only with the sequential speeds. Random read/writes would be about the same but the other things such as latency might be different due to USB (that protocol isn't very suited for data transfers; too heavily cpu-bound).
Also, thumbdrives are not designed to run operating systems from, SSD's are (there are exceptions to this such as the special thumbdrives for Windows 8 To Go). When it comes to price...from what I recall there isn't that much difference so I'd definitely go for the USB3 SSD if it has to be an external drive. If not then I'd replace the internal drive. It saves space on the desk and you don't have a problem when you pull the plug by accident.
 
sui.page said:
So my question is would it be possible to run OSX and all my applications off a single 128GB USB 3.0 thumb drive?
Click to expand...


Remember you also have the SDXC slot.
I have run my mac's off of both USB and SD cards on a temporary basis without any real issues except speed.
The high-speed cards/thumb drive cost a lot more than normal speed cards/thumb drive.
Since most of OS X is static I'm not sure the garbage collection would becoming issue very quickly.
Anyway it would be a good experiment and really won't cost too much to try. Let us know how it turns out.
 
Just out of curiosity, I ran a Black Magic Disk speed test on my 32GB USB3.0 Corsair Voyager thumb drive. It showed around 50 MB\s read and write speeds. Exactly half the speed of the factory spinner in my 2012 Mini.
 
sui.page said:
Running OSX of USB 3.0
Click to expand...
You can use one of the new Samsung 840 Evo SSDs inside an external USB 3.0 enclosure which should support the UASP (USB Attached SCSI Protocol). Apple USB 3.0 drivers support the UASP (Windows 8.x supports also the UASP).

Enclosures which do not support the UASP reduce the read/write performance and increase the access times. Regarding the reliability of TLC-based SSDs:
http://us.hardware.info/reviews/417...-with-final-conclusion-final-update-20-6-2013
 
Dual hard drive setup with a flex cable?

After reading all the posts it looks like this might not be a great option as USB weren't designed for this. I don't want to have to spend extra money after finding out the USBs don't work as I thought.

However I found another option. Would these dual hard drive flex cables work on the latest 2013 Mac mini? I would just run a dual SSD + HDD setup like I do with my Macbook Pro, I've never had a problem. I'm not sure what the internals of the Mac mini is like but would this be another possibility?
 
[[ After reading all the posts it looks like this might not be a great option as USB weren't designed for this. ]]

Perhaps USB3 _flash drives_ weren't designed for that, but a USB3 enclosure with an SSD in it will run beautifully. That's what I'm using now -- have been set up this way since January, no problems.

The Oyen enclosure in post 10 above would work fine.

I use a USB3/SATA "docking station" from plugable.com wih an Intel 520 series SSD inside. Original speeds were 410mbps (read) and 247mbps (write).
 
There's almost no difference in speed between running a drive internally or via USB 3, so use which ever method works best.

When I upgraded to an SSD I took the Mini's original hard drive out, left the OS installed, and boot from it externally with an Apricorn SATA Wire 3.0 adapter. It's my test bed before installing new software or editing configuration files on my primary drive. Blackmagic speed test reports read and writes of around 105MB/s.

I like the Apricorn adapter because it's inexpensive and about as minimal as you can get - USB on one end, SATA on the other, and the drive is bus powered. I even use the USB 2.0 version to attach a hard drive to my Airport Extreme. Works great.
 
sui.page said:
So my question is would it be possible to run OSX and all my applications off a single 128GB USB 3.0 thumb drive? This way I could even have a setup where I have 256GB(two 128GB USBs) of flash memory plus the 500GB HDD stock storage. This might even be cheaper than buying a single SSD drive. Then on top of that I'd have the flexibility of carrying around my data on those USBs if I needed. That would be a dream!
Click to expand...

Thumb drives tend to be slow. And I mean sloooooow. USB 3.0 doesn't help at all, because it is the thumb drive itself that is slow, not the USB connection. You can buy external SSD hard drives for not that much more money which should work a lot better.
 
old-wiz said:
I don't think the thumb drives have the write speed and long term reliability to work for this type of usage.

Thumb drives are prone to going bad anyway.
Click to expand...

I have a Sony 3.0 usb thumb stick that does 120 read 50 write.

It's one of the fastest and very expensive however... I got it for a cheap price ($30)

http://www.amazon.com/gp/product/B006EK6BT4/ref=oh_details_o00_s00_i00?ie=UTF8&psc=1

Actually, it looks like the 64 gb version is currently $2 more at $70. If you were looking for a good, really fast 64 gb thumb drive at a decent price, there you go..
 
Last edited:
As an Amazon Associate, MacRumors earns a commission from qualifying purchases made through links in this post.
gnasher729 said:
Thumb drives tend to be slow. And I mean sloooooow. USB 3.0 doesn't help at all, because it is the thumb drive itself that is slow, not the USB connection. You can buy external SSD hard drives for not that much more money which should work a lot better.
Click to expand...

Not all thumb drives are slow.

SanDisk Extreme 64GB USB 3.0 Flash Drive Review

For running an OS, what's important to look at is random small file (4K) transfer speeds and not the faster large file sequential read and write speeds that are usually posted on the box. A lot of USB flash drives and SD cards have lousy small file performance, and will function rather poorly as an OS drive versus a SSD. That's understandable because, given the traditional role these drives are used for, manufactures design them for large media file transfers. However, as an emergency boot drive or OS test bed, a drive like the Sandisk Extreme above does handle small files efficiently and will work just fine.
 
RE: using USB 3.0 Thumb Drives

Yes, there are many that are quite fast.

The issue is that most weren't designed for tens of thousands write cycles. They were designed to be shuttle drives for occasional use.

If you are wanting an external stroage device to use for running the OS:
- you'll not want to have the swap file or temp files on the thumb drive. Modern OS will load into RAM and run from there, but still write to the boot drive; a lot, unless you take steps (or the OS design takes steps) to keep everything in RAM
- use a storage device designed for repeated Writes; what we call SSDs. These come with SATA, mSATA, and PCIe interfaces these days. Yes, you can place these devices into USB or Thunderbolt enclosures for easy external connection
 
corvus32 said:
Not all thumb drives are slow.

SanDisk Extreme 64GB USB 3.0 Flash Drive Review

For running an OS, what's important to look at is random small file (4K) transfer speeds and not the faster large file sequential read and write speeds that are usually posted on the box. A lot of USB flash drives and SD cards have lousy small file performance, and will function rather poorly as an OS drive versus a SSD. That's understandable because, given the traditional role these drives are used for, manufactures design them for large media file transfers. However, as an emergency boot drive or OS test bed, a drive like the Sandisk Extreme above does handle small files efficiently and will work just fine.
Click to expand...

From this amazon link:

http://www.amazon.com/gp/customer-m...XA5S8/ref=cm_ciu_pdp_images_1?ie=UTF8&index=1

In real world tests the Sandisk Extreme does the same as my Sony Micro Vault.
 
As an Amazon Associate, MacRumors earns a commission from qualifying purchases made through links in this post.
You must log in or register to reply here.
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.
Top Bottom
Back