Fast external drive to road-test Big Sur?

[Frank O]

I have a 2018 i9 MacBook Pro currently running Catalina. Now that macOS 11.2 is out, I'd like to install Big Sur on an external drive so that I have ample time to kick its tires before considering doing a clean install of it on the internal drive.

Two questions. The first is choosing a good, fast external drive for this install. When I recently ran disk access tests, I was getting read and write numbers like the following:

MBP's 4 TB internal SSD: ~2600 MB/s

Samsung Evo 2 TB SSD w/ Ugreen adapter attached to Thunderbolt 3 port: ~400 MB/s

I'd like a fast external drive (preferably SSD), but don't want to spend a huge amount. Should I go with another Samsung Evo 2, or is there anything significantly faster in the same price range?

The second question: Is there a good, comprehensive step-by-step guide to installing Big Sur on an external drive? I've seen bits and pieces around, but am wondering if there's a particularly good instruction list for someone who's never done an install like this.

Thanks in advance --

 

[pshufd]

I don't think that the speed of an external drive has that big of an effect if you're just trying out the OS unless you plan to be doing very large numbers of reads/writes. I think that it's pretty easy to tell whether or not you like the UI and general performance. If you have particular programs to test, then disk performance can be a factor.

One of my systems was accidentally upgraded and I had a lot of problems as a result. Lots of beachballs and performance issues. I restored to Time Machine. I think that this was 11.1. I tested Big Sur on a virtual machine when it first came out and it had some quirks which annoyed me and decided to stay with Mojave on my Macs. We have a MacBook Air/M1 and it runs fine on that system.

 

[Frank O]

I don't think that the speed of an external drive has that big of an effect if you're just trying out the OS unless you plan to be doing very large numbers of reads/writes. I think that it's pretty easy to tell whether or not you like the UI and general performance. If you have particular programs to test, then disk performance can be a factor.

One of my systems was accidentally upgraded and I had a lot of problems as a result. Lots of beachballs and performance issues. I restored to Time Machine. I think that this was 11.1. I tested Big Sur on a virtual machine when it first came out and it had some quirks which annoyed me and decided to stay with Mojave on my Macs. We have a MacBook Air/M1 and it runs fine on that system.

Yes, I know from reading posts here that reactions to Big Sur vary widely -- many love it, some don't. I just want to take it slowly, as any functional problems would be a big deal. I guess I'll use the Samsung SSD for the Big Sur test install unless someone comes along soon with a better idea.

 

[Frank O]

Incidentally, re my second question, does anyone have a suggestion for a good step-by-step checklist on installing Big Sur on an external disk?

 

[pshufd]

Incidentally, re my second question, does anyone have a suggestion for a good step-by-step checklist on installing Big Sur on an external disk?

I usually just google install <os> on external disk and use one of the articles at well-known news websites. I will often just double-click the installer, have it format the external drive and then install there.

 

[ght56]

I think installing on your current SSD is fine.

However, do note that Big Sur entails a firmware update, and if you install onto an external drive, I am not sure if it will result in the MBP performing this update or not? (someone else might be able to clarify)

 

[BrianBaughn]

To get comparable speeds (to your internal SSD) on an external you'd have to get a Thunderbolt housing with a fast, blade SSD in it.

This video on building your own has a lot of good info:

 

[Frank O]

To get comparable speeds (to your internal SSD) on an external you'd have to get a Thunderbolt housing with a fast, blade SSD in it.

This video on building your own has a lot of good info:

Thanks! That clarified why I'm seeing the speeds I am, and how to increase them. Even if it doesn't make that much of a difference for a Big Sur tryout, a faster external drive will be a huge plus for transferring large file sets.

 

[ght56]

Thanks! That clarified why I'm seeing the speeds I am, and how to increase them. Even if it doesn't make that much of a difference for a Big Sur tryout, a faster external drive will be a huge plus for transferring large file sets.

If you are often transferring huge files (say on the order of 20 GB+), then it can be very pronounced. If the drives are both formatted to APFS and you are generally working with smaller files, there may be no real advantage at all. In some cases with really small files, certain SATA SSDs may have better performance than some certain NVMe SSDs.

You can increase the Evo's speeds a bit by using a USB 3.2 gen 2 (10 Gbps) enclosure, and you should be closer to 500-550 MB/s.

 

[Frank O]

If you are often transferring huge files (say on the order of 20 GB+), then it can be very pronounced. If the drives are both formatted to APFS and you are generally working with smaller files, there may be no real advantage at all. In some cases with really small files, certain SATA SSDs may have better performance than some certain NVMe SSDs.

You can increase the Evo's speeds a bit by using a USB 3.2 gen 2 (10 Gbps) enclosure, and you should be closer to 500-550 MB/s.

Thanks. A typical transfer for me would be 30 to 50 1-GB files. So not exactly huge files, but they add up.

 

[Fishrrman]

OP:

I strongly agree with the idea of testing Big Sur on an EXTERNAL drive before committing yourself to the upgrade.
That's exactly the way I run BS now... on an external drive.
I'm actually using a 7,200rpm platter-based hard drive in a USB3/SATA dock.
BS run surprisingly well on this (although booting isn't particularly fast).
I sense it would run MUCH better on an external SSD.

My suggestion for a little more speed that should yield reads in the 750-800MBps range or higher:
- get an "nvme" blade drive of your choice.
- get a USB3.1 gen2 enclosure (many available)
- put the drive into the enclosure, use disk utility to format it to "APFS with GUID partition format".
- install Big Sur onto that.

Here's the enclosure I use (although not for my Big Sur install):

ORICO M.2 SATA B+M/B Key SSD Enclosure USB 3.1 Type C 5Gbps External Solid State Enclosure Adapter for 2280/2260/2242/2230 M.2 NGFF SSD 4TB Max, NOT Supoort PCIe NVMe/AHCI M.2 SSD-Black

12 MONTHS FREE REPLACEMENT AND LIFETIME TECHNICAL SUPPORT: If there was any problem with the products from ORICO Direct Store, please contact us, you will get a free-replacement within 12 months.

www.amazon.com

All you really need is around 250gb for the nvme drive -- will allow the OS, apps, a basic account, etc.
Or... get 500gb or 1tb.

There's no special trick to installing BS on an external drive.
Just wait until the installer asks you WHERE you want to install.
Then, "point the way" to the external drive.

At some point when your "testing" is done, you can just erase the drive and use it for other purposes...

 

[IowaLynn]

May i recommend the Samsung T5 in 1TB capacity. Or at least 500GB...

 

[Frank O]

There's no special trick to installing BS on an external drive.
Just wait until the installer asks you WHERE you want to install.
Then, "point the way" to the external drive.

Thanks. Is there any trick to getting the MBP to boot Big Sur from the external drive when it's attached?

 

[Fishrrman]

"Is there any trick to getting the MBP to boot Big Sur from the external drive when it's attached?"

How to boot from an external drive:
a. Press the power on button
b. IMMEDIATELY hold down the option key and KEEP HOLDING IT DOWN until the startup manager appears
c. Select the external drive and hit return.

Once booted, you could open startup disk and set the external as the boot drive, but then the Mac will always "be looking for" the external when it starts.

For a laptop, I think the "option key trick" is best.

 

[Frank O]

May i recommend the Samsung T5 in 1TB capacity. Or at least 500GB...

Thanks for the suggestion. I needed more external storage anyway, so I ordered a Samsung T5 as well as the NVME SSD and enclosure mentioned in the video BrianBaughn posted, plus the Orico case that Fishrrman posted about.

The T5 is nice and small. With Blackmagic disk speed test, I'm seeing 487 MB/s write and 520 MB/s read on my 2018 i9 MacBook Pro with Catalina, which is reasonably close to Samsung's claim of "up to 540 MB/s." This is with the T5 formatted as delivered with ExFAT. Carbon Copy Cloner author Mike Bombich recommends the T5 (for Catalina and newer), so I'll probably format this one for APFS and use it for CCC backups.

The NVME SSD (Sabrent Rocket) and Orico enclosure also arrived. I'm seeing ~950 MB/s both read and write with them on the 2018 MBP. I gather that the Orico case is the limiting factor, as the other enclosure from the link above, from Trebleet, claims up to 2800 MB/s. I haven't received the Trebleet yet so can't confirm that. It's also worth noting that the Trebleet is almost 4x the cost of the Orico. So I guess it's worth deciding what speed you need vs how much to spend.

At this point I'll probably format the Sabrent Rocket with APFS and use it with the Trebleet enclosure for the Big Sur tryout. It seems like that would eliminate any possible speed issues with Big Sur performance due to external drive access. When that trial is done, I'll probably format the Sabrent with ExFAT and use it with the Trebleet for transfers of moderately large file sets (30-50 1-GB files at a time) between Mac and Windows.

 

[IowaLynn]

I bought a couple T7 SSD Samsung, 900-1100MB/sec. One 500GB for CCC and 1TB for either storage or Time machine (overkill). but not every Mac does well. But with one of your Thunderbolt 3 ports/cable very good and great at moving GBs of files.