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JedNZ

macrumors 6502a
Original poster
Dec 6, 2015
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Deep South
I'm trying to work out the best way to configure my drives so that I get the most speed out of them.

My Samsung 850 EVO 500GB contains macOS 10.12 and all my applications with little User data, and is attached to an OWC Accelsior S 2.5" PCI4 card giving me SATA-III speed (bootable). My main User data (1.5TB) is on a Seagate 3TB HDD, plugged into Bay1, and I have a 2TB and a 3TB HDD in two of the other Bays, plus a 1TB HDD in the spare Optical Bay.

My 3TB User drive is the weak link as far as speed goes. Having the SSD in the PCIe card gives me exceptionally fast boot and application launches. But I want to get another SDD (I'm looking at the Crucial MX300 575GB - anyone got a bad experience with these?) to create a Fusion Drive for my User 3TB so that I can get some more speed when I open/save/copy/move files etc. I can't afford to buy a huge >2TB SSD.

So I need to find out the best way to configure my drives.
1. Is it possible to create a Fusion Drive (FD) with a SSD in the Accelsior S PCIe card and a HDD in one of the normal direct connect Bays, or do both the SSD and the HDD have to be in the Bays?
2. Would my system benefit more from having the SSD FD (containing my User data) in the Accelsior PCIe card, or am I best to have my boot SSD (containing the OS and all my Apps) in the PCIe card? More simply put, would my boot OS or my User data FD benefit more from SATA III?

I'm noticing a slight speed increase having the boot SSD in the PCIe versus having it in one of the direct connect Bays. But I seldom see read/save bursts over 200MB a second when opening apps so don't know if it is really making the best use or needs SATA-III capability. Opening/saving/copying files is all done on my User HDD, and I often see read/write speeds up to 120MB a second, which is the best I can expect from a mechanical HDD on the SATA-II direct connect bays.

I'm just waiting for an Intel Xeon X5680 3.33GHz 6-Core CPU to arrive so I can upgrade from my 2.66GHz Quad core - that should give me a handy boost. Getting a dual CPU tray is just too expensive (unless someone knows of a cheap place to get them). And I have a USB powered Mini PCIe card for my WiFI ac/BT 4 on the way too so I'll have Continuity/Handsoff. Any advice on what else I can do to upgrade my cMP is welcomed.
 
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OK, so Fusion Drive is what you want. You sound like you know the hardware, but not how the software works with the hardware. CoreStorage (CS) is what is used to manipulate the files on a Fusion Drive. It's not quite like Dynamic drives as Windows users know them. CS is pretty smart. It keeps track of what files are used at boot, and ensures those files are stored on the SSD. Next it looks at the files themselves, if it is an application that is used more often than not, it stores it on the SSD. Commonly opened large user files are also stored on the SSD. If you aren't using up more space than what is on the SSD it just uses the SSD to store all of your files. It only starts to shift things around when you are using more space than what is available on the SSD.

Now a Fusion Drive is essentially one logical volume that spans 2 physical disks. What you need to do is init both the SSD and the HDD, then create a Fusion drive using both of the disk, once you've done that CS will handle the rest.


To sum it all up:
Build a fusion drive unless you want a logical separation of data between two physical disks. Small user data files do not open any quicker on a SSD than on a HDD. OS, Application, and large file (>30 MB) load times are faster.
 

JedNZ

macrumors 6502a
Original poster
Dec 6, 2015
644
247
Deep South
You're using an R9 380X in OSX?
Yes - my 5770 gives me boot screens, and the R9 380X drives my Samsung 28" 4K monitor at 3840x2160 60Hz. Must admit the text is small on the 4K, but I've gotten used to it. I LOVE the huge screen real estate it gives me.

Update:
I've actually got my NVIDIA GeForce GT 120 doing the boot screens for me as I didn't have enough PCI ports to have the USB3 card + R9 380X + Accelsior S (SSD). The 5770 takes up 2 PCI slots. The GT120 also doesn't have extra power requirements.
 
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JedNZ

macrumors 6502a
Original poster
Dec 6, 2015
644
247
Deep South
Cheers mildocjr. I did create a FD in my previous iMac, and it made all the world of difference, but don't have an intimate knowledge of the inner ins-and-outs.

My plan was to create a FD just for my User data, with the hope that often-used files get pushed to the SSD part of the FD, which would speed up the opening/saving/copying of these files - much faster than doing it all exclusively on a conventional mechanical HDD.

I understand how it works when you have an OS on a FD - CS copies the OS and often-used files onto the SSD. But I want to keep my OS and Apps on the separate SSD, and want (fingers crossed if it's possible - hence why asking) my User files to have some/all of the benefits that CS and FD give.

So does CS work on a FD that only has User data (no OS files)? Or does it only work - or work best - when it has the OS and User data on it? If CS can optimise the often used files on a FD with only User data, then that's what I'm looking for as it means my User data will be served at SSD-like speeds, rather than mechanical HDD speeds.

And so to repeat, if I can get the benefits of CS on a FD with User-only data, would I bet best to have both the HDD and the SDD in the direct connect bays (SATA-II) and the OS SSD in the PCIe card (SATA-III), or the other way around?
[doublepost=1476482295][/doublepost]
PCIe SSD RAID
My Accelsior S PCIe card only has room for one 2.5" SSD drive. Can you software RAID an SSD in a direct connect Bay with another one in a PCIe slot?

My User data is so huge that RAID-ing two SSDs doesn't help me speed up the User data, which is the bottleneck I'm wanting to address. I can't afford to buy a 2TB or larger SSD - that would be the ultimate solution.
 

h9826790

macrumors P6
Apr 3, 2014
16,656
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Hong Kong
Can you software RAID an SSD in a direct connect Bay with another one in a PCIe slot?

You can software RAID whatever you want. You can even RAID a USB stick with you HDD.
[doublepost=1476491169][/doublepost]
My User data is so huge that RAID-ing two SSDs doesn't help me speed up the User data, which is the bottleneck I'm wanting to address. I can't afford to buy a 2TB or larger SSD - that would be the ultimate solution.

Not understand what you mean. 2 SSD in RAID 0 = double the SSD Speed.

It's independent to your user data size.
 

JedNZ

macrumors 6502a
Original poster
Dec 6, 2015
644
247
Deep South
Okay. What I want to achieve is much faster User data transfers, and I'm wondering if having all of my User data in a Fusion Drive would net me faster (SSD-like) speed (note: the FD doesn't contain macOS or Apps - they are on another SSD). But also, if I can use FD for my User data, am I better to have the FD SSD in the Accelsior S PCIe card, or the macOS SSD in the PCIe card.

My current setup:
A 500GB SSD (in my Accelsior S PCIe card) for macOS and Applications.
And a 3TB (3.5") HDD with all of my User data in one of the direct connect Bays.

What I want to have:
A 500GB SSD for macOS and Applications.
A Fusion Drive (a new 575GB SSD + my 3TB HDD) for all of my User data.
Would this Fusion Drive with all of my User data (no OS or Applications) get the same sort of near-SSD experience that you would get if the Fusion Drive had an OS on it? That is: does CoreStorage still do it's thing with just User data and no OS or Apps?

The second matter is… if I can have a FD with just User data:
1. Am I better to have the macOS SSD in the Accelsior S PCIe card, and then have the Fusion Drive SSD + 3TB HDD both in direct connect Bays - or
2. Have the macOS SSD in one of the direct connect Bays, and have the Fusion Drive SSD in the Accelsior S PCIe card and the 3TB HDD would naturally be in another of the direct connect Bays?

I think I'll need to draw a diagram if this is still confusing to anyone. Appreciate the help though.
 
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JedNZ

macrumors 6502a
Original poster
Dec 6, 2015
644
247
Deep South
Will do - thanks for that.

I ended up getting a Crucial MX300 750GB SSD and have Fusion Drived it with a WD Black Caviar 2TD - SSD in Bay1 and the HDD in Bay2.

Once the User data has been cloned across I'll benchmark it, then swap the Crucial SSD into the Accelsior S PCIe and run benchmarks again. My early thought is that my User data (on the Crucial SSD) will benefit more from the SATA-III speed in the Accelsior PCI card than my Samsung 850 Evo boot SSD will. I'll post my results (if it works).
 

JedNZ

macrumors 6502a
Original poster
Dec 6, 2015
644
247
Deep South
Have successfully created the Fusion Drive with the Crucial MX300 750Gb and the WD Black Caviar 2TD HDD. But when copying files (1.8TB worth) using the Finder (and also tried with Carbon Copy Cloner) the Fusion Drive gets unmounted some of the way through and the transfer stops. Has happened 4 times all up. I have checked the drives are seated correctly in their direct connect Bays, and have swapped them over (SSD in Bay1 and HDD in Bay2, and vice versa) but still get the issue of the FD crapping out. I have to do a restart after the FD fails each time as the FD disappears from the Desktop and can't be seen in Disk Utility.

I have resorted to copying each folder in my User account, one by one, so I don't overwhelm the FD. That seems to be working. I can see the Expansion Slots fan (~1800rpm) and the Power Supply fan (~1100rpm) ramping up and down throughout the copying, so wonder if it's an overheating/power supply issue. The drives themselves are around 30˚C each, so they don't appear to be overheating.
 

h9826790

macrumors P6
Apr 3, 2014
16,656
8,584
Hong Kong
Have successfully created the Fusion Drive with the Crucial MX300 750Gb and the WD Black Caviar 2TD HDD. But when copying files (1.8TB worth) using the Finder (and also tried with Carbon Copy Cloner) the Fusion Drive gets unmounted some of the way through and the transfer stops. Has happened 4 times all up. I have checked the drives are seated correctly in their direct connect Bays, and have swapped them over (SSD in Bay1 and HDD in Bay2, and vice versa) but still get the issue of the FD crapping out. I have to do a restart after the FD fails each time as the FD disappears from the Desktop and can't be seen in Disk Utility.

I have resorted to copying each folder in my User account, one by one, so I don't overwhelm the FD. That seems to be working. I can see the Expansion Slots fan (~1800rpm) and the Power Supply fan (~1100rpm) ramping up and down throughout the copying, so wonder if it's an overheating/power supply issue. The drives themselves are around 30˚C each, so they don't appear to be overheating.

The fan issue looks like from your 380x, try run Luxmark for few seconds and then stop it, the fan should back to normal.
 

JedNZ

macrumors 6502a
Original poster
Dec 6, 2015
644
247
Deep South
Finally got all my User data onto the Fusion Drive, but it unmounts and disappears from the desktop every couple of hours resulting in a hang/crash (even when the Crucial SSD was in the Accelsior S PCIe card). Hopeless.

I create another Fusion Drive with a smaller WD S 120GB SD with the (same) WD 2TB HDD, and copied a smaller User account over and it didn't have a problem, so think the issue is with the Crucial SSD. That was an expensive, time wasting exercise.Grrr!
 

JedNZ

macrumors 6502a
Original poster
Dec 6, 2015
644
247
Deep South
My Accelsior S PCIe card failed so I had to RMA it to OWC - they were terrific and sent a replacement out quickly.

So I've got my macOS on the Accelsior S (Samsung 850 EVO SSD), and my main User data is still on a 3TB Seagate ST3000DM001 7200rpm. I have another admin account on the SSD for troubleshooting, or if the 3TG fails or isn't connected when I boot.

Okay, so I've got a new scenario I want feedback and advice on. I've been reading up on M.2 and the huge speed increases over SATA 2 (in my direct connect bays) or SATA 3 (on my Accelsior S PCIe card).

I don't generally (hardly ever, if at all) see my SSD working at/near SATA 3 speeds - I can't see what it does on startup, but when opening apps it doesn't ever burst to the upper reaches of SATA 3. I'm happy to keep my macOS partition on this PCIe card.

What could really do with a boost (Photos, Photoshop files, Final Cut X and Motion X files, gaming etc) though is my User data. I tried to Fusion Drive (FD) the previous Crucial 750GB SSg with my 3TG HDD, but that failed cos the SSD failed. I returned it and got another Samsung 850 EVO 500GB SSD, and use that now for Windows 10 (awesome boot times, and gaming now). I was too scared to burn out another SSD - I have 1.8TB of User data to transfer to it.

Q1: But does anyone know if it's possible to FD a Samsung 960 M.2 NVMe in a PCie card with a 3TB HDD (direct connect bay - SATA 2)?
Q2: What speed improvements I could expect?
Q3: If it is possible, what size M.2 card would be optimum, given that FD pushes most-often used data to the faster partition (i.e. M.2) side of the FD? Would 250GB or 500GB be best, or would it have to be larger?
Q4: Would this be the best (and probably last) upgrade I could do (without breaking the bank)?

I play with much the same games on Steam on my macOS boot as I do on the Win10 boot, but my user experience is that it's slightly faster in Win10 because it's running solely off a SSD (both the Win OS and the User data), as opposed to my current set-up of macOS on the SSD in the Acclesior S PCIe card and User data on the 3TB HDD.

I often see the 3TB HDD pushing data up to 180MB/s (hardly the max for SATA 2), so know that my macOS system is often wanting files from my User account fairly quickly. If I had a Samsung 960 M.2 NVMe in a FD, it could push that data so much more quickly, but only if it's possible.

Has anyone else done something like this that can share their experience, either way?
 

JedNZ

macrumors 6502a
Original poster
Dec 6, 2015
644
247
Deep South
Looks like no one else may have tried putting a M.2 PCIe in a Fusion drive with a HDD just for the User data files. Just looking for a cheap SM961 256GB to arrive and I'll try it out and report back my results.

My intended plan is:
Currently have Samsung 850 EVO 500GB in a PCIe Sata III card for my boot (macOS and all my apps, plus a spare Admin User account).
Create a FD with a M.2 PCIe 256GB and my 3TB HDD just for the User data.

If anyone knows this won't work please let me know as every time I play around with my User data, Photos wants to sync my entire 250GB of photos and videos up to iCloud again (getting Fibre 960/400 installed next week, which will make it much faster to upload this, but still a painfully slow experience - just want to use my machine without it being tied up having to sync Photos for 2 to 3 days).
 

h9826790

macrumors P6
Apr 3, 2014
16,656
8,584
Hong Kong
Looks like no one else may have tried putting a M.2 PCIe in a Fusion drive with a HDD just for the User data files. Just looking for a cheap SM961 256GB to arrive and I'll try it out and report back my results.

My intended plan is:
Currently have Samsung 850 EVO 500GB in a PCIe Sata III card for my boot (macOS and all my apps, plus a spare Admin User account).
Create a FD with a M.2 PCIe 256GB and my 3TB HDD just for the User data.

If anyone knows this won't work please let me know as every time I play around with my User data, Photos wants to sync my entire 250GB of photos and videos up to iCloud again (getting Fibre 960/400 installed next week, which will make it much faster to upload this, but still a painfully slow experience - just want to use my machine without it being tied up having to sync Photos for 2 to 3 days).

The FD won't magically speed up the data transfer rate. As long as the data still stored in the HDD part, the data transfer will max at 180MB/s (exactly the same rate before you create FD).

FD is just a tech that the system will analysis which files are frequently accessed by the user, and automatically keep those files in the SSD part, but allow the less frequent accessed files transfer to the HDD part.

If your most frequently accessed files are that 250GB photo / video library (because the iCloud sync keep accessing them). That 250GB data will occupy the whole SSD (in you FD), and all other data will be stored on the HDD part, and still transfer at the same rate.

You may end up have that 250GB data has quick access avail, but mainly for iCloud sync (which is slow anyway). And all other data has no quick access.

If you need / want high sequential read speed all the way. Pure PCIe SSD is the way to go, no 2nd choice.
 
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JedNZ

macrumors 6502a
Original poster
Dec 6, 2015
644
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Deep South
Hmm, thanks for that. Can you or anyone confirm that FD would infect transfer the full Photos package file to the SSD, or if FD can see the individual items within the package? If it only see the whole Photos Library package file, and therefore transfers the whole/entire photo library package to the SSD, then I would need to get a 500GB or larger M.2 SSD, otherwise the FD would spend most of it's time swapping in and out the Photos library file.
 

h9826790

macrumors P6
Apr 3, 2014
16,656
8,584
Hong Kong
Hmm, thanks for that. Can you or anyone confirm that FD would infect transfer the full Photos package file to the SSD, or if FD can see the individual items within the package? If it only see the whole Photos Library package file, and therefore transfers the whole/entire photo library package to the SSD, then I would need to get a 500GB or larger M.2 SSD, otherwise the FD would spend most of it's time swapping in and out the Photos library file.

It's down to every single individual file / item, and move the less frequent accessed photos (inside a library) to the HDD.
 

usna92

macrumors member
Mar 16, 2011
99
11
Seattle
I am looking at similar configurations now on which would be faster. I am planning on using a recycle MacBook Pro Retina SSD with a Seagate Momentus 750GB drive (the one with a built in SSD cache) as a FD and then creating a soft JBOD with the other 2 other drives in the drive bays and then a final drive as a time machine back up of the FD setup. I haven't figured out what I am going to do with the 2nd optical bay yet. I have another SSD lying around, but will need to get some things to connect it in.
 

JedNZ

macrumors 6502a
Original poster
Dec 6, 2015
644
247
Deep South
Still waiting for my M.2 to arrive - could be a couple of weeks. I'm keen to learn how you go with the recycled SSD you're going to use for your FD usna92.
 

usna92

macrumors member
Mar 16, 2011
99
11
Seattle
Well the plan should be executed tomorrow, so I'll let you know. The last piece comes tomorrow, so I should be able to slap it together by tomorrow night. I am sure I will have missed something easy and make a hash of it, but you never know. :)
 

itdk92

macrumors 6502a
Nov 14, 2016
504
180
Copenhagen, Denmark
I litterally don't get why people even tinker with stuff like Fusion Drive.

It's meant for the consumers who do not even know what an SSD is.

You need speed? just buy a (pcie) SSD. You want space? Get a HDD, or a HDD raid.

I would get OCD just at the thought of not knowing where stuff actually is :D

*sorry for the radical 2c
 
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usna92

macrumors member
Mar 16, 2011
99
11
Seattle
No worries. I agree with you, were this a production, real work machine. This is a reclaim my rMBP from home server duty and install this in its place machine, and allow me to run multiple monitors at decent frame rates when I working on some coding projects on the side. I am trying to expend minimal capital while I do it, which means, I have to use whatever I have sitting around on shelves. Were it a money is no option thing, I would go for a 4-way raid SSD with spinning disk to back it up and eSATA card to speed ip the internal drive and fully push speed out to my drive arrays. Unfortunately, its constrained by budget, so whatever I have on the shelf, plus around $200-$250 including processors, will eventually have to what is spent on this at the time. The reason I have that SSD around is that I had to replace the one in my rMBP because I was constantly shuffling data on and off, rather doing more meaningful things. So I have that, a few other spinning disks, with the momentum being the other strong performing drive. It becomes the fusion boot drive, which will have a CCC bootable backup should something unfortunate happen. If it turns out to just be a total dog, I'll nuke it and something else will come along.

But keep the comments coming. You all have much more time in these machines than I do, so I am learning from the options people suggest.
 

JedNZ

macrumors 6502a
Original poster
Dec 6, 2015
644
247
Deep South
It's a money/cost thing for me too. I have almost 2TB of User data, and when I do a bit of video/audio work (add another 500GB while I'm working on it - archived to another HDD as soon as it's rendered) my HDD does it's SATA II best, but it's the bottleneck. If I can create a FD using a M.2 NVMe SSD paired with my 3TB HDD then I nibble/chomp away at some of that bottleneck. I simply can't afford to buy a 3TB or bigger SSD to replace my HDD. I also don't have spare direct connect bays free to set up a RAID of HDD, and even if I did this it wouldn't come in anywhere near as fast as a M.2 NVMe.
 
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