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Turnpike

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Oct 2, 2011
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If I have a new iMac Pro base model, and use a 2TB Samsung T5 external SSD as my hard drive, I won't notice much of a difference in performance, would I? My goal is to be able to unplug it at the end of the day and take it with me, so others can use the computer and I can work on my things at home on my MBPro.

The T5 has a pretty fast read write speed (one of the fastest from what it seems after some online searching) so there would be virtually no downside as far as performance for using the external SSD as my hard drive, would there? It connects by USB-C, so...?


Just double checking before I order the Samsung T5. Thanks!
 
If you need 2TB in space then the T5 is your best option IMO. It's fast enough for most uses but much slower than the internal SSD. If speed is more important than space, for a similar amount of money you can buy the Samsung X5 1TB which is roughly the same speed as the internal SSD, I wouldn't recommend paying for a 2TB X5 in most cases. Another option could be to use both the 500GB X5 and 1TB T5 at once, presuming you'll have two ports free.
 
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"If I have a new iMac Pro base model, and use a 2TB Samsung T5 external SSD as my hard drive, I won't notice much of a difference in performance, would I? My goal is to be able to unplug it at the end of the day and take it with me, so others can use the computer and I can work on my things at home on my MBPro."

There is no way in h--- that an external SSD is going to be anywhere near the speed of the internal SSDs on the iMac Pro (even the "base model").

If you want to transfer your working/personal data back-and-forth with you, of course you can do this.

But there's absolutely no need that you have to BOOT FROM your external SSD when connected to either computer (work or home).

Just keep a "data folder" on the portable drive, and access that from either Mac.

IMPORTANT:
You better make sure that before you travel between work or home, that you've backed up your latest data (on the portable drive) to either Mac. What would happen if you somehow lost that drive, or it got damaged?
 
If you need 2TB in space then the T5 is your best option IMO. It's fast enough for most uses but much slower than the internal SSD. If speed is more important than space, for a similar amount of money you can buy the Samsung X5 1TB which is roughly the same speed as the internal SSD, I wouldn't recommend paying for a 2TB X5 in most cases. Another option could be to use both the 500GB X5 and 1TB T5 at once, presuming you'll have two ports free.


Thanks everybody for the info- I appreciate it so much. And yes! This is just what I was looking for- Cost is not an issue, so if the X5 is faster, that's the kind of option I'm looking for. I didn't even know about such a thing till I read this and looked it up. Thank you!
 
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Just keep a "data folder" on the portable drive, and access that from either Mac.
Depending on your applications, you may find that you will have read/write privileges to your work files from only one of the Macs and not the other.

This is easily fixed in About This Mac but there are a number of steps. If you find this to be an issue, give a shout.
 
I’m using a 2TB Samsung T5 with my 2017 iMac as a “permanently connected’ external drive. The iMac has a 512GB internal SSD. The T5 is plenty fast enough and is formatted APFS. However, it is significantly slower than the internal SSD. It connects via a TB3 port but is in reality using a USB-C connection.

I would put the performance at between a mechanical HDD and the very fast internal SSD of the iMac. I can run some benchmarks of the 2TB T5 if you’re interested. I know that the performance wasn’t up to the official figures of the T5 but it’s perfect for daily use.
 
mike wrote:
"Depending on your applications, you may find that you will have read/write privileges to your work files from only one of the Macs and not the other."

Seems to me that this can be easily over-ridden by setting both the work Mac and home Mac to "ignore ownership" (under sharing and permissions) of the "travel drive".

With that done, any file copied from the travel drive to either Mac will fall under the "ownership" of the Mac that's accessing it. "Back and forth", back-and-forth, so to speak.

I swap files all around 3-4 Macs here (at home) and never have "permissions problems" at all. And each Mac "is its own Mac" with distinct user accounts, etc.
 
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I was running my iMac on a T3 for a while and it was just as fast (if not faster) then the internal Fusion drive.

Just so folks don't get confused when reading this thread, the Samsung T3 would appear to be just as fast as Apple's Fusion Drive on a regular iMac, but for the sake of this discussion, we're comparing it to the ultra-fast SSD in the iMac Pro.

If I have a new iMac Pro base model, and use a 2TB Samsung T5 external SSD as my hard drive, I won't notice much of a difference in performance, would I? My goal is to be able to unplug it at the end of the day and take it with me, so others can use the computer and I can work on my things at home on my MBPro.

The T5 has a pretty fast read write speed (one of the fastest from what it seems after some online searching) so there would be virtually no downside as far as performance for using the external SSD as my hard drive, would there? It connects by USB-C, so...?


Just double checking before I order the Samsung T5. Thanks!

In order to answer your question of whether or not the T5 is fast enough, we need to know what your needs are.

Before we get started with that, I am assuming you are talking about storing your data on the Samsung T5 and not booting the iMac Pro from the Samsung T5. If you do prefer to boot from an external drive, keep in mind that you will lose many of the security features from the iMac Pro's T2 chip.

Back to using the Samsung T5 to storing your data, if you are simply doing everyday office/life work, then you will not notice any slowdown at all. If you are simply accessing photo projects and doing normal editing, you will not notice any slowdown. If you are editing single-stream 4K video, you will not notice any slowdown. However, if you are editing intensive multi-cam 4K video, then you might start to see a bottleneck. Of course, there are many more usage applications than just photo and video work, but I use that as a reference since that is the large majority of my work. So back to the original question: what are your usage needs? Let us know and we can get you a solid answer.

As for me, the projects I'm actively working on in my editing suite are stored on my iMac Pro's internal 4TB SSD drive. This gives me ultra-fast unfettered access. Then when I'm finished with the job or the task at hand, I send that data over to an external Thunderbolt 3 RAID 5 array. I also travel a lot (about 130-140 days a year) so I have a couple of 2TB Sandisk Extreme Portable SSDs that I use in the field in conjunction with my MBP. Then when I get back home, I simply plug them into my iMac Pro and resume my work. The Sandisk Extreme Portable SSDs are faster than the Samsung T5 and are cheaper if you catch them on sale. They are slightly larger than the Samsung T5 though, but not by much. Anyway, I thought I would mention the Sandisk to you since you're in the market for a very fast, small portable SSD drive.

Bottom line: small portable SSD drives can be a great way to bounce your work between a desktop machine and a laptop, but as far as "will it be slower", it all depends on the work you're doing.

Edit: After posting this, I happened to check B&H Photo and discovered that the 2TB Sandisk Extreme Portable SSD is on a super sale for $379, but only until Nov 3. This is significantly cheaper than the Samsung T5. The Sandisk is well regarded and loved by many. Mine have been great. And good grief, this is a great price!

https://www.bhphotovideo.com/c/prod...sk_sdssde60_2t00_g25_extreme_600_2tb_ssd.html
 
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Just as a data point, here's some disk benchmarks of my 2TB Samsung external SSD running on a 2017 iMac, connected via a USB-C cable to one of the iMac's TB3 ports.

lnrurz0.png
 
...if you are editing intensive multi-cam 4K video, then you might start to see a bottleneck....I'm actively working on in my editing suite are stored on my iMac Pro's internal 4TB SSD drive....Then when I'm finished with the job or the task at hand, I send that data over to an external Thunderbolt 3 RAID 5 array. I also travel a lot (about 130-140 days a year) so I have a couple of 2TB Sandisk Extreme Portable SSDs that I use in the field in conjunction with my MBP....The Sandisk Extreme Portable SSDs are faster than the Samsung T5 and are cheaper if you catch them on sale... I happened to check B&H Photo and discovered that the 2TB Sandisk Extreme Portable SSD is on a super sale for $379, but only until Nov 3.

As of today both Amazon an B&H have both 2TB Samsung T5 and Sandisk Extreme for about $397. The 3rd party tests I've seen show about the same read/write performance for each -- however most people just test large sequential transfers, not small random I/O.

Even though for video editing we normally focus on sequential IO (which the Blackmagic test measures), with FCPX certain tasks can entail a significant % of small random IOs. This comes from the SQLite database calls, thumbnail generation, waveform generation, updating metadata, etc. In this case SSDs are even more advantageous.

E.g, in sequential IO the portable 4TB Lacie Rugged RAID HDD does about 220 MB/sec, which is roughly 1/2 the performance of the Samsung T5. However for small random IOs, the performance difference can be 50-to-1 in favor of the SSD. In fact for some small random IO profiles the T5 is nearly as fast as the iMac Pro internal SSD.

But it's also important to not over-exaggerate real-world SSD advantage. I've done lots of editing on various single SSDs, SSD arrays, single HDDs and HDD arrays, and for 4k H264 the regular IO rate just isn't that high. For low-compression codecs like ProRes or DNxHD, IO is more of a constraint.

Also many times (esp with H264) video editing is CPU or GPU limited, not IO limited. In those cases increasing IO perf by 100x won't make the task much faster, but it will consume money that might have been better spent elsewhere.

I have two 2TB Samsungs and they are really great at the $380-$400 price point. However (even at that low price) they are still 2.6x more expensive in cost per MB than the 4TB Lacie Rugged RAID. If you just need 2TB why not get the SDD. But if you need 20TB, the price difference really adds up.
 
You need a better enclosure then. Those speeds are terrible.

Is it really that bad? His previous post indicates it is a Samsung T5. The box states "up to 540 MB/s transfer speed". It comes in it's own enclosure. For USB 3, doesn't seem too bad to me.
 
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I just ordered a 970EVO 1TB for about $230 and USB-C enclosure for another $75, so about $300 all in. Wasting some of the speed capability of the drive, but it just about fully saturates USB-C 10Gbps according to BlackMagic Disk Speed Test. So it was cheaper than the 1TB equivalent T5 and X5, but not nearly as fast as the latter. Doesn't seem like the 2TB 970EVO is even close in price, though, for what you originally were looking for.
 
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Thanks everybody for the info- I appreciate it so much. And yes! This is just what I was looking for- Cost is not an issue, so if the X5 is faster, that's the kind of option I'm looking for. I didn't even know about such a thing till I read this and looked it up. Thank you!

Just so you know the X5 won't work with non-thunderbolt enabled USB-C ports. It's the reason I bought a regular Samsung T5 2TB drive instead of it as I want absolute interoperability between devices - not just a really fast drive limited to a couple of devices.
 
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Just so you know the X5 won't work with non-thunderbolt enabled USB-C ports. It's the reason I bought a regular Samsung T5 2TB drive instead of it as I want absolute interoperability between devices - not just a really fast drive limited to a couple of devices.
Thanks for sharing that info! I haven't entered the USB-C world yet with my personal computers, so it was good to see this on the T5 Product site
"** T5 is compatible with USB 3.0 and USB 2.0."
 
Thanks for sharing that info! I haven't entered the USB-C world yet with my personal computers, so it was good to see this on the T5 Product site
"** T5 is compatible with USB 3.0 and USB 2.0."

There's a Thunderbolt chip (Titan Ridge) that would allow external drives to connect with either USB or Thunderbolt. It's been available since January 2018 but I've yet to see any shipping devices.
 
Thanks for sharing that info! I haven't entered the USB-C world yet with my personal computers, so it was good to see this on the T5 Product site
"** T5 is compatible with USB 3.0 and USB 2.0."

The Sandisk Extreme Pro Portable SSD is the perfect external drive.
Support top speeds over TB3 and USB. Definitely worth considering as it’s the first external SSD without any drawbacks.

https://www.sandisk.com/home/ssd/extreme-pro-portable-ssd
 
here is no way in h--- that an external SSD is going to be anywhere near the speed of the internal SSDs on the iMac Pro (even the "base model").

iMac Pro 4 TB SSD

BlackMagic DiskSpeedTest SSD iMac Pro  .png

External 2.0TB OWC Envoy Pro EX with Thunderbolt 3

Blackmagic OWC SSD 2 TB pre Mohave.png

I'd call it a tie.
 
I should have qualified my statement by saying external "USB" SSD!

But the OP's post was comparing the speed of a USB drive (not thunderbolt) to the speed of the internal drive.
And again, I'll restate -- nowhere near the speed!

Samsung X5 (or equivalent) -- yes.
Samsung T5 - NO.
 
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iMac Pro 4 TB SSD

View attachment 857551

External 2.0TB OWC Envoy Pro EX with Thunderbolt 3

View attachment 857552

I'd call it a tie.
Nice speed, however you are comparing the iMac Pro's internal NVME drive with an external NVME drive so the speed should be the same. I have the same setup. SSD's, while once thought really fast, are much slower and the 400-500MBs is about right. They are certainly fast compared to a HDD, but not a NVME drive.
 
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SSD's, while once thought really fast, are much slower and the 400-500MBs is about right.

I would word it differently. The term SSD is generally refers to the package, which consists of the semiconductor cells, their associated support circuitry which could be a RAID configuration, controller, and then the interface. The interface could be PCIE, NVME, or whatever. The term "SSD" can mean a lot of things.

The fastest one I know is the Lqid HoneyBadger, which can be sized up to 32 TB, and runs up to 24 GB/s. That is BYTES/s, not BITS/s! One of the investors in Liqid is Phison which makes SSD controllers. Couldn't find the price, likely that of a nice car.


 
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