Fair enough, but that is a pretty major point to set aside. Bootcamp is a very significant reason for all-SSD setups. Win 10 is, IIRC, optimised for SSD and this is very noticeable at boot time.
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Real-world speed differences between Fusion drive and SSD on latest iMac 27"
- Thread starter twilexia
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Benchmark wise there is no question the SSD will blow the Fusion drive away especially if you are running tests that constantly transfer 100 GB files from one place to another. Again that's why I wanted to focus on real world performance. How in your view will SSD help you in terms of everyday tasks?
I think we're in agreement here, it's just I'd like the discussion to focus purely on OSX because once we start talking about users of Bootcamp, it's pretty cut and dry that SSD is the best option for them. Well, Fusion drive can still run bootcamp so if you're one of those people who primarily use OSX but use Bootcamp to run some games you like, the slower bootcamp speed won't affect your real-world performance that much.
I think you misunderstood me. I wasn't implying of creating a fusion drive like that. You possibly could if you put a spinner in a thunderbolt enclosure, but I've never tried that before. I was suggesting of going a big SSD plus a USB 3.0 big HDD so you get the best of both worlds.
That's the thing you can't discount the speed difference the ssd makes in bootcamp. Before I got a separate Win10 gaming machine, I trudged along with my 3TB fusion in bootcamp, performance was plain horrible as games would take FOREVER to load up (as I said I've been spoiled with SSDs for 5 years already) that's a real world issue. Also, I will routinely download over 100gb of 4K footage and 36MP RAW files from my AX100s/D800/D810 and that easily overloads my 128gb SSD (in my fusion setup) and will start to slow down noticeably while just downloading the files and when editing them. That blackmagic test showing 600mb/sec is not SUSTAINABLE when you continue to write to the fusion and exceed the free space on the 128gb SSD. It will drop into the 125mb/sec range or whatever the spinner is capable of.
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Got it. I did misunderstand you then, my apologies. I like your solution actually of using an external fusion drive, but once we start talking about external drives then it doesn't really matter what one is using for their internal drive.
Let's create a simple flowchart:
Keep in mind that I'm only considering applications and their respective data, not your family photos/videos.
It's really very simple, either you need much storage and fork up the money for SSD, either you need much storage and settle for Fusion Drive or you don't need much storage and go with the SSD.
- Do you need more than 256 GB of storage for your applications?
- No => Get the 256 GB SSD
- Else proceed
- Do you need always super-fast load times?
- Yes => Is the 512 GB / 1TB SSD worth the money to you/Can you afford it?
- Yes => Get SSD
- Else proceed
- Else proceed
- Yes => Is the 512 GB / 1TB SSD worth the money to you/Can you afford it?
- How much storage do you need for your applications?
- 3 TB or less => Get appropriate sized Fusion Drive
- Else proceed
- Get external drives
Keep in mind that I'm only considering applications and their respective data, not your family photos/videos.
It's really very simple, either you need much storage and fork up the money for SSD, either you need much storage and settle for Fusion Drive or you don't need much storage and go with the SSD.
I for one actually find this to be an extremely helpful discussion and appreciate what the OP is trying to get at. Many, but not all, of the people who frequent this site are into the minutia and are on the extreme end of their computer useage. One could easily come away from these forums with the idea that regardless of useage if you can afford it "buy up". And that goes for CPU, GPU or hard drive.
In my case, I am contemplating replacing my late 2009 i7. I probably fall somewhere between a typical consumer and. Prosumer. I do a reasonable amount of photo editing of RAW files using Lightroom, Photoshop, etc. and I also do some fairly basic audio recording/editing. I may do some video editing as well, but again it is pretty basic stuff, at least at this stage.
My current iMac has a 2TB hard drive and I like having everything internal with just a single external used for a time machine backup. I was thinking that for the next computer I would get a 512GB SSD and external storage, but after reading all of these responses perhaps a 3 TB fusion drive would make more sense.
Anyway, thanks for the topic. It is both timely and useful from my perspective.
In my case, I am contemplating replacing my late 2009 i7. I probably fall somewhere between a typical consumer and. Prosumer. I do a reasonable amount of photo editing of RAW files using Lightroom, Photoshop, etc. and I also do some fairly basic audio recording/editing. I may do some video editing as well, but again it is pretty basic stuff, at least at this stage.
My current iMac has a 2TB hard drive and I like having everything internal with just a single external used for a time machine backup. I was thinking that for the next computer I would get a 512GB SSD and external storage, but after reading all of these responses perhaps a 3 TB fusion drive would make more sense.
Anyway, thanks for the topic. It is both timely and useful from my perspective.
Thanks. Great flowchart, but I think a lot users don't know if they need 512 GB or 1 TB. They may be a youtuber or twitch streamer just starting out, or they may be an amateur photographer. And it definitely comes down to a preference thing at the end - do you want super fast load times for all applications (i.e. click everything on your dock and have everything load instantly) or would the fusion drive loading your most-used apps quickly and giving you additional storage be good enough? And do you absolutely hate external drives or don't mind them?
The thing is, all of these are preference questions. Which is irrelevant to the topic of real-world performance, the question of How much of an upgrade speed difference will users see with the 1TB SSD vs 3TB FD in everyday work and real-world performance situations (gaming, video/audio/graphics production, coding, etc)
Of course, that flowchart is assuming you know how much storage you actually need - which can be difficult for average users to know. Real-world performance difference between SSD and FD for regular users is negligible. But if you know you don't need more than 256 GB storage, I would still recommend going with the SSD instead of the 2 TB FD (same price).
For me, it's quite easy. I have a NAS where I store all my media files, documents, videos (backup), photos (backup) and I use iCloud Photo Library to keep my photos/videos accessible from all my devices. I also have Crashplan as an offsite backup solution to back up my entire NAS to in case of break-ins/fire/etc. For movies, I use Netflix/Viaplay streaming, otherwise I'd use my NAS for locally stored movies.
So when removing all media files out of the equation, coupled with the fact that use webmail (so no mail-caches on the computer) and not that many applications (I'm a casual user), following the flowchart; 1. Do you need more than 256 GB storage for your applications? No => Get the 256 GB SSD.
I deliberately choose to remove media files from the equation in the flowchart since I belong to the party that thinks it's bad practice to keep them on your regular computer - but that's a whole different discussion so let's not dive into that.
Again, I'd like not to focus on the bootcamp because bootcamp means you are comparing SSD to HDD. That's a lot different than comparing SSD to FD.
However your observation about downloading 100gb of 4k footage overwhelming your 128GB SSD is very relevant. So would you say that for video producers working with a lot of 4k video footage, there is a performance benefit for having the SSD over FD? What about video producers who don't work with as much footage as you? When does the HDD portion of the SSD kick in during a large file transfer, assuming you have 1TB of the Fusion drive already filled up? And how much slower is this going to impact your workflow, and are you doing this downloading every day or once a week?
twilexia wrote above:
"Benchmark wise there is no question the SSD will blow the Fusion drive away especially if you are running tests that constantly transfer 100 GB files from one place to another."
Really now -- how many people who own iMacs are regularly in the business of "constantly transferring 100gb files" ?
My guess is, "not many". Perhaps a few. Again, not many.
There's no doubt that a "straight" SSD will yield performance that is "faster than" a fusion drive.
But for the overwhelming majority of users, the speed of the most recent fusion drive setups with a PCIe-based SSD is so fast, they'll never notice [what could be] the difference.
If you happen to -be- one of those folks that -does- notice, well, then.... that's why Apple offers you the opportunity to purchase an iMac with a "straight" PCIe-based SSD...
"Benchmark wise there is no question the SSD will blow the Fusion drive away especially if you are running tests that constantly transfer 100 GB files from one place to another."
Really now -- how many people who own iMacs are regularly in the business of "constantly transferring 100gb files" ?
My guess is, "not many". Perhaps a few. Again, not many.
There's no doubt that a "straight" SSD will yield performance that is "faster than" a fusion drive.
But for the overwhelming majority of users, the speed of the most recent fusion drive setups with a PCIe-based SSD is so fast, they'll never notice [what could be] the difference.
If you happen to -be- one of those folks that -does- notice, well, then.... that's why Apple offers you the opportunity to purchase an iMac with a "straight" PCIe-based SSD...
Again I feel like this is just deriding the FD to slow load times, which isn't the case at all. How about we agree on fast load times instead of "super" fast for the FD. OS X is also pretty effective at caching/RAM as well, which I definitely felt on my previous HDD only machines.
Many fusion drive benchmarks are flawed because they test empty drives while HDD access speed slows down once the space is filling up pushing data to outer side of the disks. Real test will be having 60-70% fusion drive filled up and performance the benchmark.
It's interesting that despite you imploring people to focus on real-world performance, they cannot resist continuously talking about benchmarks and perceived reliability differences.
I have six Macs, four with SSD and two with FD. I have extensively tested in real-world video editing my top-spec 2013 iMac 27 with 3TB FD vs my 2015 top-spec iMac 27 with 1TB SSD.
In general I don't see much difference in real-world performance between the 3TB FD and 1TB SSD iMac that could be attributed to I/O. That said, most of my media is on external storage but that is often a requirement for video editing if your boot drive is 1TB or less. So this has to be mentioned since real world use often mandates it.
Beyond a certain point, faster I/O benchmarks do not necessarily translate into faster real world performance. The app itself must need that I/O performance and be capable of generating the I/O rate to harness the platform capability.
In many cases the app does not need and cannot use extreme I/O performance because it is already bottlenecked somewhere else. Video editing is a good example. Many common codecs are highly CPU-intensive and the software rapidly becomes CPU limited. The situation is similar with CPU or GPU-intensive effects; the I/O rate is not very high. You are typically waiting on the CPU or GPU, not on I/O. Anyone who doubts this can see it themselves by using Activity Monitor or iStat Menus during video editing.
Lower compression codecs like ProRes can produce a higher I/O rate and hence need more I/O capability, but the file size can be 8x to 10x larger. Hence it won't fit on internal SSD so the higher performance is a moot point.
I mildly prefer my SSD iMac 27 over the FD version but not because it produces huge real world performance differences. It is faster in some things and the performance is more consistent but the real world difference is usually not huge.
A 3TB iMac 27 has more space than current SSD options and for certain mid-range use cases that is useful. However for video editing you normally don't want your media on the boot drive, even IF there is sufficient space. If you must use external storage anyway, there's a good argument for SSD, even if the real-world performance difference isn't huge.
Thanks. Your posts have done a lot to debunk the common theme going around this forum/the internet in general that Video editing requires high I/O. As you mentioned there are so many factors that go into video editing that I/O is usually never the bottleneck.
I'm just curious where are all the SSD evangelists? Because so far the only person to give their opinion on the different groups of users is user iemcj (who in fact disdains Fusion drives):
It seems only graphic designers benefit greatly from SSD vs Fusion drive. Everyone else either doesn't use enough I/O bandwidth, or is using external drives as internal storage is limited.
I'm looking at upgrading to new iMac.
I presently have an external (spinner) drive via FW800 to use Windows via Parallels. I also have a Windows partition on the internal 3 TB drive (I installed).
Would running Windows via the "File" method on a iMac with a 3TB fusion drive, be acceptable?
I presently have an external (spinner) drive via FW800 to use Windows via Parallels. I also have a Windows partition on the internal 3 TB drive (I installed).
Would running Windows via the "File" method on a iMac with a 3TB fusion drive, be acceptable?
I/O *can* be the bottleneck in video editing and even well known experts like Larry Jordan often mention this. This leads people to assume you simply must have SSD for video.
However there is a difference between *can* be vs the common case with HD H264. In times past video was transcoded before editing to a lower-compression codec, which increased I/O load. Today on big productions they shoot with low compression codecs like ProRes 422 or RED Raw. In those cases I/O is very important -- although it would never fit on most affordable SSDs.
Below this level it is very common in Premiere and even FCP X to edit the native HD H264 camera files. The editing software and hardware has progressed to that point. Those are highly compressed and greatly reduce the I/O.
Moving to 4k it will again become more common to transcode simply because many computers can't handle the CPU load. That will again increase the I/O load, requiring much more bandwidth.
Most people aren't shooting or editing 4k or ProRes, much less raw. For that class of production, it is not as I/O intensive as many people think.
I see. Thank you so much for all the info you're providing to us.
Is there a way to check how many mb/s your video is being played back at? What about the NTSC format vs H264 (apologies, I'm an amateur video maker, despite having made hundreds of videos)
Thank you for your insightful information.
Could you be more specific about the "not so huge differences" that you noticed between SSD and FD?
And, I'd like to know why you think putting media on the boot drive is not a good idea.
The video is encoded at a rate you can usually inspect with tools like MediaInfo (free): https://mediaarea.net/en/MediaInfo or Invisor ($2.99): Invisor - Media File Inspector on the Mac App Store
Both of those place a menu in Finder under Services so you just right-click on the video file then select Services, then either MediaInfo or Invisor.
There is much more extensive video header information available with the command-line tool ExifTool: http://www.sno.phy.queensu.ca/~phil/exiftool/
During playback the actual I/O reading rate can be inspected with Activity Monitor, iStat Menus or similar tools. However the reading rate is often "bursty" and fluctuating. If the player is showing you all the bits, you can approximate the reading rate by dividing the number of megabytes by the duration of the video.
There SSD in my 2015 iMac is much faster than the 3TB FD in my 2013 iMac. However the FD is still pretty fast and from a real world standpoint when doing video editing, it doesn't make a huge difference -- provided the media is external.
The Will Smith feature film "Focus" was edited in FCP X, mostly on an iMacs and MacBook Pros. The lead editor's machine was an iMac 27 with 3TB Fusion Drive. The media was on a large Thunderbolt array.
For higher-end work it is standard practice to not put media on the boot drive. It is handling the OS, app loading and sometimes temp and scratch files. Putting the media external to this helps divide the I/O workload, get more I/O parallelism and avoid bottlenecking on the boot drive.
Newer generations of SSD boot drives are extremely fast and this could theoretically change the traditional performance picture -- if they were only big enough. Even a 1TB SSD is small when dealing with 4k video or even large amounts of raw high megapixel stills. You don't have the full 1TB since the OS and apps use a lot of that plus you need some reserve space.
Due to the I/O bandwidth, the difference is bigger when the media is in FD in other words?
While the FD is pretty fast it has limited I/O bandwidth relative to SSD. In addition to the OS and apps if the media is on there plus the hidden work/render files from an app like FCP X, it can saturate the capability.
For lower end things you can put media on the FD and it is OK. There is no clear, fixed limit on this because all apps and workflows are different. In general using iMovie to edit short cell phone videos is OK, but using FCP X to edit 4k video is not OK. In between there is some threshold where it becomes increasingly difficult. What that is varies with different situations.
The problem with internal SSD is even though it has the bandwidth it's not big enough to put much media on it -- depending on what that media is. It can hold a lot of .jpg photos. It cannot hold a lot of 4k video and larger numbers of 40 megapixel raw stills from new cameras will exhaust it faster than you'd expect.
My wife has a 2012 iMac 27 with 3TB FD and all her media is on it -- but that is only .jpg cell phone photos and short videos, plus a few iTunes movies and things downloaded from our Tivo. It works fine and there are no performance problems and she'll have plenty of space for years.
I have the new Skylake iMac with 1tb ssd. Tonight I selected 36 jpgs shot with a Nikon D810, hit cmd c, went to another folder, hit cmd v. They copied instantly . No blue progress bar. It was the first time I noticed the speed of the ssd.