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Trogledyte Mac

macrumors regular
Original poster
Oct 15, 2006
129
2
Hi all,

I want to split the 1T fusion drive in 2 partitions:
1 partition for starting up and all the system files van Os x Snow Lion and some other...
This partition is about +- 150 GB or less.
The other partition will be +- 850 GB for data files, music, movies and photo's.

Is this OK, or do I missing something?

Regards,
Mac.
 
Its ok, but there's no need for such a division. You'll not gain any performance increase or keep your data safer since its on the same physical drive (more or less because of the nature of the fusion drive).
 
splitting fusion

i think the best what you can do with the fusion drive is to split it to two separate drives (apple ssd and apple hdd) and then have system on ssd and use the HDD for data (linking pictures, movies, music, and so on, to home folder from the HDD)... that way you will have maximum speed as whole system with all apps is on SSD, and you saving the SSD lifetime because all the data is on HDD, just linked into home folder. i dont like the idea of moving whole home folder to HDD because of lots of small files, settings and so on. It should increase overall speed, and increase lifetime of ssd.
 
That will definitely work but you lose the benefit of Fusion, but your storage will be on the larger (and slower) hard drive.

In the enterprise we always split the OS from the data, but for Macs there's generally little call. Because of the nature of Fusion you can live with Fusion and work with a single volume or split the drives as you mentioned which is not a bad idea.
 
I thank you both :cool:

So if splitting is not a problem..... I do it.
@ Ppq Your answer intrigues me!
Can you or anyone tell me how to split "apple ssd and apple hdd"
I'm not so a comp. technoid :D

Thanks and regards,
Mac.
 
There is absolutely no point in making two partitions on a unix system unless you are technically competent and know what you are doing and why you are doing it.
 
I want to split the 1T fusion drive in 2 partitions:
1 partition for starting up and all the system files van Os x Snow Lion and some other...
This partition is about +- 150 GB or less.
The other partition will be +- 850 GB for data files, music, movies and photo's.

Is this OK, or do I missing something?
You are missing the entire point of the Fusion drive. The Fusion drive automatically and intelligently moves files (actually, data blocks which can be smaller than whole files) between the SSD surface and the Hard Drive surface.
This gives you fast speeds and large capacity.

Splitting it up is pointless -- there's not point in having it.
 
Hi all,

I want to split the 1T fusion drive in 2 partitions:
1 partition for starting up and all the system files van Os x Snow Lion and some other...
This partition is about +- 150 GB or less.
The other partition will be +- 850 GB for data files, music, movies and photo's.

Is this OK, or do I missing something?

Regards,
Mac.

Yes. You are missing a lot. The underlying mechanisms of a Fusion drive are so much more efficient than you at managing your drive for speed and efficiency.

For instance, even though the SSD is limited in size, it reserves space for caching HDD operations. Improving overall drive response. The partition you would create loses that additional layer of caching, slowing down access speeds to your data.

The only reason to partition would be for loading multiple OS, i.e., Boot Camp.
 
You are missing the entire point of the Fusion drive. The Fusion drive automatically and intelligently moves files (actually, data blocks which can be smaller than whole files) between the SSD surface and the Hard Drive surface.
This gives you fast speeds and large capacity.

Splitting it up is pointless -- there's not point in having it.

There is absolutely no point in making two partitions on a unix system unless you are technically competent and know what you are doing and why you are doing it.

Ok, like I said I’m not a computer technoid. I only have for the moment a backup drive for 500 GB (usb2) and a 1T (usb3) for work & data....
So I thought that it would be easier to backing up regularly +- 200 GB or less.
Is that a wrong thought?
I'm not buying direct a New Drive for the moment... maybe end this year...
Still wrong for splitting?

Regards and thanks,
Mac.
 
Ok, like I said I’m not a computer technoid. I only have for the moment a backup drive for 500 GB (usb2) and a 1T (usb3) for work & data....
So I thought that it would be easier to backing up regularly +- 200 GB or less.
Is that a wrong thought?
It is most useful if you use Time Machine to back up your ENTIRE data -- including the system.
You should aim for a backup drive that is roughly 3 times the size of the drive/data you are backing up.
 
It is most useful if you use Time Machine to back up your ENTIRE data -- including the system.
You should aim for a backup drive that is roughly 3 times the size of the drive/data you are backing up.

Yes, that is what I was thinking of 3T for backing up... but not for now! So again, is it a problem to make 2 partitions +- 200 & 800 GB for the time being... until I bought a 3T drive... just for being save and to be able for backing up?

Regards,
Mac.
 
Hi all,

I want to split the 1T fusion drive in 2 partitions:
1 partition for starting up and all the system files van Os x Snow Lion and some other...
This partition is about +- 150 GB or less.
The other partition will be +- 850 GB for data files, music, movies and photo's.

Totally counter productive. Depending on how clever the fusion drive is, what you want to do will either not give you any benefit whatsoever, or it will hurt performance badly. I suspect it is the latter.

If there is something you don't want to back up, you can select that in Time Machine, although I wouldn't recommend it. I'd especially recommend backing up the system; if something goes really wrong (like total destruction of your Mac), you can just restore from Time Machine and everything is back to normal.
 
So again, is it a problem to make 2 partitions +- 200 & 800 GB for the time being... until I bought a 3T drive... just for being save and to be able for backing up?
  • Do not split your Fusion Drive.
  • Use an external drive for backing up.
  • Don't backup to a PARTITION on a drive, if you also have data on another partition. (You will lose everything if the drive fails.)
  • Don't split your Fusion Drive.
 
Yes, that is what I was thinking of 3T for backing up... but not for now!

"But not for now" is the important phrase. My question is, how much system/applications/data will you be putting on that 1TB drive for now? If it's anything close to 1TB, then you should be wondering first whether you should get the 3TB Fusion drive.

If you are currently using substantially less than 1TB (let's say, you currently have a computer with a 500GB hard drive)... then you just have to worry about backing up 500GB for now.

I have a 250GB iMac right now (about 60GB free disk space) I've been using a 500GB external drive for Time Machine backup. The entire Time Machine backup set (full and incremental backups) is 415GB.

Based on my experience, if you currently have a 500GB internal drive, then you could use that 1TB external drive for Time Machine without a hitch, and use the 500GB external drive for some other purpose. What happens in a year or so, as you fill more of the new computer's HDD... by then you could consider a new external drive for backup.

FYI, Time Machine (and any other good backup software) maintains only one full backup, plus many incremental backups (the stuff that's changed since the last full backup). Time Machine keeps hourly backups for the past 24 hours, daily backups for the past month, and weekly backups going back (in my case) to July 2012. Plus the full backup. All on a drive twice the size of the HDD it's backing up.
 
Thank you ApfelKuchen :cool:
The 1T is for 90% full...
So I will go for the 500 GB HD and I will only use a 150 or a 200 GB system & date on the Fusion HD until I have the 3T HD.
That's why I thought (no more) it was necessary to split the Fusion HD.

Thanks all,

Regards,
Mac.
 
You can exclude big folders with non-critical files (like your movie collection) from the time machine backup. Actually, I only backup my Documents directory, because everything else is very easily recreated in case of a system failure.
 
So let me get this straight. If i have 1T fusion drive, i will use bootcamp for windows 7 so i will have 100Gb for windows partition and the rest for MACOS.

I understand that the 100GB will be on normal HDD and will work only at 5400rpm/7200rpm but what about MACOS partition, after it gets over 128GB will be still automatically put on SSD drive the application that you use the most?
 
http://www.macworld.com/article/2015664/how-to-split-up-a-fusion-drive.html

Data does not have to be loaded at 400MB/s (photos, movies, music)...
It's just killing ssd.

Fusion is awesome for regular user, but i wonder how long the ssd will survive when using fusion... using it as buffer for hdd intended for data is a quite pricey...

Splitted fusion drive = better control over ssd usage, much more lifetime...

+ http://blog.alutam.com/2012/04/01/optimizing-macos-x-lion-for-ssd/

It's called FUD. Fear, Uncertainty, and Doubt. You propose using your drives in a way that destroys the advantages of a Fusion drive, without giving any reasons other than totally unfounded and wrong claims.

"Better control over SSD usage". I'll give you an example. The iTunes app on my Mac is just over 300 MB. Without a Fusion drive, you have two choices: iTunes on the SSD drive, or iTunes on the hard drive. All 300 MB. Fusion puts _exactly_ the bits of iTunes that you are actually using onto the SSD drive, and the rest on the hard drive. Of resources in 20 different languages, the one (or for some people two) that you use are on the SSD, the other 19 or 18 on the hard drive. iTunes displays a picture of the devices plugged in. The pictures of the one or two devices that you own are on the SSD, the others are on the hard drive. So please tell me how you can control this any better, or even half as good as a Fusion drive does.
 
Data does not have to be loaded at 400MB/s (photos, movies, music)...
It's just killing ssd.

It doesn't kill anything :rolleyes:

Fusion is awesome for regular user, but i wonder how long the ssd will survive when using fusion... using it as buffer for hdd intended for data is a quite pricey...

Splitted fusion drive = better control over ssd usage, much more lifetime...

The SSD or the HDD will probably die because of unrelated reasons long before the SSD runs out of rewrite cycles.
 
The first thing I did when I got my new 27" iMac was to destroy the fusion drive.

I didn't like the idea of everything going into the SSD first and then moved to the HDD when the fusion drive deemed it was time to move them.

Another advantage to split the fusion is instead of having 1TB of fusion (1TB HDD + 128GB SSD buffer) you have a total of 1.128TB storage by actually using the SSD as storage instead of buffer.
 
Another advantage to split the fusion is instead of having 1TB of fusion (1TB HDD + 128GB SSD buffer) you have a total of 1.128TB storage by actually using the SSD as storage instead of buffer.

Its not a buffer :p Its tiered storage. You still get 1.1TB total.
 
It's called FUD. Fear, Uncertainty, and Doubt. You propose using your drives in a way that destroys the advantages of a Fusion drive, without giving any reasons other than totally unfounded and wrong claims.

"Better control over SSD usage". I'll give you an example. The iTunes app on my Mac is just over 300 MB. Without a Fusion drive, you have two choices: iTunes on the SSD drive, or iTunes on the hard drive. All 300 MB. Fusion puts _exactly_ the bits of iTunes that you are actually using onto the SSD drive, and the rest on the hard drive. Of resources in 20 different languages, the one (or for some people two) that you use are on the SSD, the other 19 or 18 on the hard drive. iTunes displays a picture of the devices plugged in. The pictures of the one or two devices that you own are on the SSD, the others are on the hard drive. So please tell me how you can control this any better, or even half as good as a Fusion drive does.

Nope, all i say you wear your ssd way too soon comparing to split drive and that is true as all you write on disk is going through the ssd first.

And youre wrong because fusion does not care about files. It works with blocks of data... And in those blocks you will always have some data you dont need.

And please tell me how to tell fusion drive manually to not handle my data folders through ssd, as it's useless... I want to choose which stuff don't touch ssd at all and which folders will stay still on hdd. For me, fusion drive is useless, and contraproductive. The only reason i ordered it is the ssd itself.
 
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