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Why a Fusion Drive si better than a 256Gb SSD (personal opinion)
- Thread starter aevan
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The FD won't work "equally as good".
The drive will spin down sometimes to save energy. Spinning it back up again when you access a finder window (e.g., opening a save dialog box) will be noticeable since the Finder waits until all accessible volumes have checked in before presenting the window. This happens even if you're not going to use the spinning drive at all.
This very noticeable lag is not present in a pure SSD system.
If you do not need the space, SSD is objectively better.
I have direct experience with this since the iMac I have uses an SSD paired with spinning drives for backups and large data storage whereas the rMBP is an all-SSD setup.
There is a very evident pause when you interact with a Finder-capable sheet in a program on the iMac because when you click "save" or "open" (for example) the sheet appears and you can hear the drives spinning up. Only once they're ready can you interact with the window (even to save/open files that are on the SSD).
Edit: just to be totally 100% ultra clear on this, I'm not talking "theoretical talk" or "empty trash vernacular" (wtf?) here, I'm talking actual real world usage in the real world reality that exists and has been experienced by me directly.
Haven't noticed any of that. But you say that you have an iMac with SSD + HDDs and you notice slowdowns because of the HDD part, isn't that exactly the same as having a pure SSD + HDD external storage? Again, for the Nth time, I'm not comparing a Fusion Drive to a pure, 1Tb SSD, I'm comparing it to the 256SSD + External HDD.
Either way, this topic could go on and on, I'm just glad people can read different views on this and decide for themselves.
That is exactly what I am saying. I have a 256 SSD + 1TB HDD not fusion linked.
The Finder has very noticeable pause any time it makes a system volume call because it spins up any drives that are mounted but not immediately active.
This means that if you don't need the space, having an HDD mounted on your system *even if you do not use it* is objectively worse than just having a pure SSD system.
Are the SSD and HDD in that machine fused, or running independently? The difference would be that a Fusion Drive is treated as a single logical volume. There is no waiting for the HDD to spin up (it's part of the speed advantage of Fusion, just as it would be with an HDD with integrated SSD cache). My real-world experience with Fusion is that there is no lag opening Finder. But even if it existed, the scenario described applies only if the HDD has spun-down.
Even if there was, his point is not applicable in a 256Gb SSD + HDD vs FD debate. I'm not sure what he's trying to prove - that a FD is worse then a pure SSD? Yes it is. But is it worse than a 256Gb SSD + External HDD storage? Well, his argument doesn't stand there because he himself claims there are slowdowns with his SSD + HDD setup. So how does that make 256Gb SSD + External HDD better? Either I don't understand what he's saying, or he doesn't understand me.
As for the FD, I really don't notice these slowdowns anyway. It works just like my SSD MacBook 90% of the time. 10% of the time it's a bit slower. That's it.
I don't think there is a single person on this thread who would disagree with you. The entire argument is based on needing the storage space.
Exactly. People seem to ignore the fact that it's FD vs 256Gb SSD + HDD. It's not FD vs 1Tb SSD or FD vs 256Gb SSD + External Thunderbolt SSD or FD vs Fairy Dust Powered Unicorn Drives.
You're one of the rare people here who didn't wander off from the question at hand. We disagreed, but at least you didn't defend the 256Gb option by pointing out that a large, pure SSD is better. It is!
I was addressing your initial arrogance to come swanning in here and dismiss anyone who disagrees with your position as having a "theoretical argument".
Your initial point was that there was no difference between a pure SSD setup (i.e. 1 single, solitary, one alone SSD with NO HDD) vs a Fusion drive setup, when there clearly is a difference.
Having a spinning drive in your system *will* introduce lag when it spins down, unless you disable the energy saver setting that spins idle drives down after a few minutes.
If you're continually using the HDD - as in a fusion setup, then the lag will be less, since the drive tends to be spun up, but then you're still dealing with HDD IO issues. If your data is small enough to fit on just the SSD portion of the fusion drive then you'd be better off with a pure SSD because in that situation the HDD portion will spin down.
If you have a split system, or multiple spinning drives attached you will notice this more frequently.
Also, how can you in one paragraph state that my argument (that pure SSD is better than FD) "can't stand" and then in the second paragraph contradict yourself and state that 1 out of 10 times it's "a bit slower" than a pure SSD.
And you're the one who says I don't understand the argument?
If your data needs are modest enough to fit on an SSD then it is objectively superior to a fusion drive, or an SSD+HDD combo. Your option with any setup that involves spinning disks is to either leave them running 100% of the time (noise, power) or to deal with the fact that any system call that polls the filesystem at the root level will cause your Mac to pause while all mounted drives report ready.
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It makes no difference - in either a split volume or a fusion drive, if the HDD is idle for long enough it will spin down, subsequently stalling the Finder when it has to spin up again when any global file system access is called (even if you only intend to access the SSD). For example, opening a save dialog from an app.
If you're actively using the HDD (i.e., your fusion data is bigger than just the SSD portion) then that's outside the scope of the argument. The original claim (that if you ran counter to you were just making a "theoretical argument") was that an SSD and an FD performed the same.
I'm simply stating that this is not the case. If your data needs fit onto an SSD (say the 256 GB one that is very popular) then it's objectively better than any system that involves an HDD (either an FD or a split SSD+HDD).
If you need the storage space and can't afford a giant SSD then you obviously have to compromise and get the fusion drive, but it *is* a compromise to do so. That's all I'm saying.
I just objected to the fact that the original poster left no room for discussion by dismissing arguments counter to his opinion out of hand right away.
No. I was clearly talking about FD vs 256Gb + external Thunderbolt HDD drive, because for most people, 256Gb is not enough space. Second, I never said there was no difference between a pure SSD and a Fusion Drive, only that most people wouldn't notice that difference in real world scenarios.
Now, I base that claim on my own experience. I just don't notice the lag you mention on my Fusion Drive and I compare it to a MacBook Pro Retina that I own and that has a pure SSD. I'm sorry, but I just don't see it, and I think most people won't see it as well.
Because you don't. 1) A Fusion Drive IS a bit slower than a pure SSD and 2) your argument can't stand because you're comparing the Fusion Drive to a pure SSD instead of comparing it to a pure SSD PLUS external HDD essentially ignoring the topic of the discussion here.
You're deliberately twisting my words. If your data needs fit onto an 256Gb SSD, BY ALL MEANS GET AN SSD, IT IS BETTER THAN A FUSION DRIVE.
My claim is that if your data requires more than a 256Gb SSD, a Fusion Drive is better than an 256Gb SSD + External Thunderbolt HDD solution. How many times I need to type that here? No, I'm not comparing it to 'pure SSD solutions'. And the reason I think it's better than just having a 256Gb SSD is that for MOST people, 256Gb won't be enough space for a main computer, and EVEN THOUGH a FD is a bit slower, that difference in speed is not a good enough reason to justify more than 4x less storage space. But if you don't need that space, of course 256Gb SSD is a better option.
So, even if the lag you describe (and I never notice) is real and 'not theoretical', your point would still be lost because that same lag would be present in the 256Gb SSD + External HDD setup (as you yourself said). So, that doesn't give the SSD + External option any advantage vs a FD. It gives the pure SSD option an advantage, BUT WE'RE NOT TALKING ABOUT THAT HERE.
I would choose the 256 GB SDD vs the FD in any case ! It is twice as fast in write speed and there is no HD inside the iMac which is not a good place for HD's. I have about 10 dead HD's laying around here out of iMacs. They are getting too hot inside it (and you hear the noise of them all the time).
I added an external 512GB TB SSD to it. This is even cheaper than the 512 GB upgrade option from Apple and gives me 254 GB more space in the end with much more performance than the FD. I can expand this with a second SSD if I like because the Thunderbolt case has an option for that.
I added an external 512GB TB SSD to it. This is even cheaper than the 512 GB upgrade option from Apple and gives me 254 GB more space in the end with much more performance than the FD. I can expand this with a second SSD if I like because the Thunderbolt case has an option for that.
I can't say anything for Fusion Drives prior to iMac 5K, but on 5K, the FD does not get too hot, the fan is not running faster, I NEVER hear the drive and what you said is simply not true in the case of the latest iMac.
And 10 dead HDDs? Seriously? I've been using computers for the past 17 years, we have around 50-60 of them at work, a lot of them for years, and I had at least 10 different computers personally, in all this time I experienced one HDD break, and it happened as a result of a defect, a few months after purchase. You must be really unlucky. Or maybe you have some heat issues, from your description it would seem your iMacs are boiling inside.
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Those were not only from my own iMacs (but at least two of them) but from several of our customers which we support for about 15 years now with Apple hardware. There is a significant amount of dead HD's in iMacs compared to other computers which is also reported from my colleagues.
Well technically it is true that 'Pure' or the dedicated SSD is the best option. But Fusion Drive is not too bad for average users like me. I have a rMBP with 1TB SSD (Installed all apps I needed and Windows 8 with Parallel) and it's fast. A month ago I bought an iMAC 5K with 3TB Fusion Drive. All my apps that I needed are only like below 60GBs in total so I don't really need more than 128GB SSD. I am a university student and I barely stay home, so I only use my iMAC like 4 - 5 hours during weekdays and about 10 hours during weekends, but I find most of the time I am using my rMBP. I basically do a bit of work on my Mac (I don't deal with intensive apps) and only use iMAC for media purpose and to download videos (MKV, BDMV, DVDISO) and yes I have USB 3.0 external drives too.
So it really boils down to what are you using your iMAC for. And if the HDD fail, I can always boot from external drive and split the drives with terminal and just use the SSD if I am out of warranty. (Mine is seagate XD, praying it would last me for more than 3 years).
Forgot to mention, regarding the noise. Yes HDD make noise as it is a spinning drive. If you are under a really quite environment like me, then yes you can hear the noise.
So it really boils down to what are you using your iMAC for. And if the HDD fail, I can always boot from external drive and split the drives with terminal and just use the SSD if I am out of warranty. (Mine is seagate XD, praying it would last me for more than 3 years).
Forgot to mention, regarding the noise. Yes HDD make noise as it is a spinning drive. If you are under a really quite environment like me, then yes you can hear the noise.
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I recently got a iMac Retina, i split the SSD from HDD, and i am extremely happy with it. I manage my home folder separate from boot partition anyways.
it is near silent, and most of my work related files (Java, Xcode , Database tools etc) perfectly fit in 128gb SSD , and photos/music/videos in HDD part.
Again, if you want a silent operation, splitting is an option.
it is near silent, and most of my work related files (Java, Xcode , Database tools etc) perfectly fit in 128gb SSD , and photos/music/videos in HDD part.
Again, if you want a silent operation, splitting is an option.
Maybe not for web browsing, etc but I would think if you video edit and render a lot like I do than it just adds more to the entire system being hot. And do hybrid drives spin if you don't overflow the SSD side of it? Your points are valid, but its still open to opinion, and some of those things still matter to some people.
I never said one option is universally better for all. I can totally imagine that for video editing and rendering a pure SSD is a better option.
Wow, this topic is still attracting replies
We think alike.
Spinners do not belong INSIDE a computer in 2015. Heat, noise and mechanical breakdown are the reasons.
You can complicate it all you want, but at the end of the day, see what I have written above.
Lol, this is getting old. I love how your arguments are dogmatic and how you didn't read a word that I said. Can we just drop the subject?
No.. Fusion drive is somewhat self optimising so it gives you the benefits of the extra capacity and performance but here's the rub with current implementations...
SATA interface, the new MacBook Pro retinas use NVM express, an interface designed around flash access and shedding the limitations of ATA as an adopting/compatible interface.
Most of the comparisons are based on SATA implementations of Flash.. I use one in my MBP at work, a Crucial 1Tb M500 drive.. many times better than the original drive but still constrained by the SATA interface.
At home I have a 1Tb Fusion Drive, infinitely better than the 1Tb drive I added to the previous iMac I ran at home (the kids have that now).
Anyway,
Fusion drive SATA is great, > drive alone.
SSD on SATA is great, > Current Fusion Drive.
NVM express will change folks perceptions for both Fusion and total Flash storage.
SATA interface, the new MacBook Pro retinas use NVM express, an interface designed around flash access and shedding the limitations of ATA as an adopting/compatible interface.
Most of the comparisons are based on SATA implementations of Flash.. I use one in my MBP at work, a Crucial 1Tb M500 drive.. many times better than the original drive but still constrained by the SATA interface.
At home I have a 1Tb Fusion Drive, infinitely better than the 1Tb drive I added to the previous iMac I ran at home (the kids have that now).
Anyway,
Fusion drive SATA is great, > drive alone.
SSD on SATA is great, > Current Fusion Drive.
NVM express will change folks perceptions for both Fusion and total Flash storage.
Ah! but what type of SSD? SATA is certainly not the future, it's just a half-way house solution. PCIe is surely the way to go - if that is you are fully wedded to getting an SSD.
I popped a 250 gig SSD in my Windows Laptop and I can't deny it's like a whole new and very different machine. I do however think the OP made some very valid points. If I was changing my iMac with the technology and prices as of this moment then I would probably get the FD.
I know they seem dogmatic. But in reality, there is a reason that Apple does not put anything but SSD's in their computers anymore, with the exception being a fusion drive. OK, the other exception is the low end iMac and Mini. Lord, those are big slow drives. 5400??? Really??? Soon cost will not be a factor, it will cost more to buy an antique spinner than an SSD.
Which is marketing fluff as an internal SSD plus an internal spinner for storage without the "fusion" would have sufficed for your arguments, but no, they had to "fusionize" it.
I really cannot believe this thread has continued on. There is just not that much going on. It comes down to personal need.
Nevertheless, one has not lived until they have used an all SSD system with further external storage needs solved by an external SSD. Prices are coming down daily on SSD's.
So I let it drop
LOL!
I know they seem dogmatic. But in reality, there is a reason that Apple does not put anything but SSD's in their computers anymore, with the exception being a fusion drive. OK, the other exception is the low end iMac and Mini. Lord, those are big slow drives. 5400??? Really??? Soon cost will not be a factor, it will cost more to buy an antique spinner than an SSD.
Which is marketing fluff as an internal SSD plus an internal spinner for storage without the "fusion" would have sufficed for your arguments, but no, they had to "fusionize" it.
I really cannot believe this thread has continued on. There is just not that much going on. It comes down to personal need.
Nevertheless, one has not lived until they have used an all SSD system with further external storage needs solved by an external SSD. Prices are coming down daily on SSD's.
So I let it drop
Just my thoughts...Spinners have no future in modern high end desktops....just one thing I was wondering about: why is the internal SSD so much faster than the external TB SATA SSD(700 MB/s read vs 380MB/s)? The SSD in the 5K iMac is no NVMe but also SATA as the external. The Thunderbolt interface should be linked relatively close to the PCIe bus.....