I wonder if that would hold true for an eSATA SSD connected by Thunderbolt hub.
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Apple's New Fusion Drive Works on Older Macs
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I wonder if that would hold true for an eSATA SSD connected by Thunderbolt hub.
His articles don't give enough detail about what he actually did. He says that drive is internal, but I don't know why the mac would see it as USB. In other posts, it looks like he tried a pci SSD card and didn't get good results with that either.
Either way, I don't agree with his conclusions, particularly that there's no benefit even when it's setup and working properly. Seems like the problems may be on his end and he has sour grapes about his lack of results.
I just did a test, it definitely looks like it's moving frequently used files to the SSD on my system. Here's what I did.
1) Load about 7 gigs of data into memory. My FD has about 300 gigs of data on it, it's made of 128 ssd plus 1TB drive. I specifically selected the later data to be copied to the drive, expecting that would be on the HD. I wasn't able to time the first load because it was a number of separate files I had to select individually - after the first time I was able to load them all with one click. But I was able to see that all data was loaded from HD, none from SSD.
2) Dump the data (I quit the app and did purge in the terminal to remove it from any memory cache)
3) Load the data a second time. Data loaded in about 3.5 minutes. Using iStat menus, I could see that the vast majority of the data was still being loaded from HD (first load looked like pretty much all data came from HD).
After the load was complete, there was heavy reading and writing on both drives for a full five minutes. I assume the system had decided that data had been accessed enough to be on the SSD and it was copied there with other files copied to HD to make room.
4) After purging again, load a third time. Third load took 1:10, all coming from SSD. There was a quick read/write at the end between the two drives.
5) Fourth load was 1:08 although the tiny difference just could be inaccurate timing on my part. All read from SSD, no write on either drive at the end.
So it looks pretty clear that the data was on HD, after a couple loads it copied that data to SSD after which loading was much faster. It's doing exactly what Apple said, frequently used data is fast from SSD, infrequently (or never) used sits on the cheap HD. And if it becomes frequently used, it gets moved.
1) Load about 7 gigs of data into memory. My FD has about 300 gigs of data on it, it's made of 128 ssd plus 1TB drive. I specifically selected the later data to be copied to the drive, expecting that would be on the HD. I wasn't able to time the first load because it was a number of separate files I had to select individually - after the first time I was able to load them all with one click. But I was able to see that all data was loaded from HD, none from SSD.
2) Dump the data (I quit the app and did purge in the terminal to remove it from any memory cache)
3) Load the data a second time. Data loaded in about 3.5 minutes. Using iStat menus, I could see that the vast majority of the data was still being loaded from HD (first load looked like pretty much all data came from HD).
After the load was complete, there was heavy reading and writing on both drives for a full five minutes. I assume the system had decided that data had been accessed enough to be on the SSD and it was copied there with other files copied to HD to make room.
4) After purging again, load a third time. Third load took 1:10, all coming from SSD. There was a quick read/write at the end between the two drives.
5) Fourth load was 1:08 although the tiny difference just could be inaccurate timing on my part. All read from SSD, no write on either drive at the end.
So it looks pretty clear that the data was on HD, after a couple loads it copied that data to SSD after which loading was much faster. It's doing exactly what Apple said, frequently used data is fast from SSD, infrequently (or never) used sits on the cheap HD. And if it becomes frequently used, it gets moved.
To answer my own question, I created a "Fusion" type drive on my 2011 Mac Mini which already had a OWC 240 GB SSD and a 512 GB hard disk installed and running. I had already set up a Windows 7 partition on the SSD and wanted to preserve that. I used the partition-diskID for the OS X partition and the full diskID for the hard disk to create the joined drive.
It WORKED!
So far, everything seems to be running as expected.
OS X is using the joined "Fusion" drive.
Windows is using the existing partition on the SSD and can be run as a boot OS or as a VM using VMware Fusion.
You may see an Apple Fusion document online which states that BootCamp cannot be on the SSD ... and they are correct in that the BootCamp partition cannot be created on the SSD (only on the hard disk) from an existing Fusion system. However, if you create that partition on the SSD prior to creating the "Fusion" array, it appears to work fine.
-howard
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I've got the first 27" iMac, a 2009 model with an i7. It would seem that I could do this hack by putting an SSD in the optical bay. I stand a pretty good chance of making this work, right?
Also, where's the best / cheapest seller of an "optibay" equivalent for the iMac?
OK, before I posted I found this on Amazon for $10.95 with strong reviews:
http://www.amazon.com/Drive-Unibody...e=UTF8&qid=1351964767&sr=1-1&keywords=optibay
That's for a MacBook Pro. I'm going to try this on a MacBook Pro first.
Still need a mounting solution for putting an SSD in an iMac's optical bay.
Also, where's the best / cheapest seller of an "optibay" equivalent for the iMac?
OK, before I posted I found this on Amazon for $10.95 with strong reviews:
http://www.amazon.com/Drive-Unibody...e=UTF8&qid=1351964767&sr=1-1&keywords=optibay
That's for a MacBook Pro. I'm going to try this on a MacBook Pro first.
Still need a mounting solution for putting an SSD in an iMac's optical bay.
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After reading these comments I started wondering if this will work with my late 2009 model Mac Mini (older design) and an eSATA JBOD enclosure.
My idea is to run a slimline SATA to eSATA (or a SATA to eSATA) cable from one of the two internal connectors, to an external 2-bay JBOD eSATA enclosure. That will allow me to use a 128 GB Samsung 830 SSD and a 3.5" server grade HDD for Fusion Drive and to keep the original 320 GB internal drive in the Mini for emergency situations.
I guess I can use a dremel to cut a hole for the cable at the back of the Mini, but I need to know that this setup can actually work. So here are my concerns:
- Can I actually use the eSATA storage as a boot drive? (I'm almost sure that I can)
- If something happens and the cable gets unplugged while the computer is running, will it cause hardware problems, or can I just format the drives or change them and continue using the Mini?
- Can I use a 4-bay enclosure with 1xSSD +3xHDD setup for the Fusion Drive? (or 1xSSD + 1x HDD for FD plus an HDD for bootcamp and another one for backups?)
Considering that I already have a 2-bay enclosure, and all the drives that I am planning to use, does anybody think it's a good idea, or is it too risky?
I need help setting this up. . .
Could someone please tell me what I'm doing wrong in setting this up? I've got a 2011 MBP with a Samsung 830 256Gb on the main drive bay (6gbps) and a Seagate XT 750 installed in the optical bay (3gbps). I'm booting 10.8.2 from a USB stick and entering terminal where I get the bash prompt (I don't know how to get the TIN> prompt, is this part of the problem?) At the prompt, I type:
"diskutil cs create MacHD disk0 disk1"
All seems to go well, except when I enter disk utility I cannot format the newly created volume (because its "locked"), so if I go back to terminal and enter:
"Diskutil cs list"
I see my volume and associated ID. I figure it needs to be formatted, so I follow the next part of the guide and type:
"Diskutil coreStorage createVolume (UUID) jhfs+ "Mac HD" 990g"
I get a error "-69780: Unable to create a new CoreStorage Logical Volume"
After that, my SSD drive disappears and I can no longer even boot from my USB stick! The only way to recover is to take out the hard drives and reformat them in another computer! Ugh!
What am I doing wrong?
Could someone please tell me what I'm doing wrong in setting this up? I've got a 2011 MBP with a Samsung 830 256Gb on the main drive bay (6gbps) and a Seagate XT 750 installed in the optical bay (3gbps). I'm booting 10.8.2 from a USB stick and entering terminal where I get the bash prompt (I don't know how to get the TIN> prompt, is this part of the problem?) At the prompt, I type:
"diskutil cs create MacHD disk0 disk1"
All seems to go well, except when I enter disk utility I cannot format the newly created volume (because its "locked"), so if I go back to terminal and enter:
"Diskutil cs list"
I see my volume and associated ID. I figure it needs to be formatted, so I follow the next part of the guide and type:
"Diskutil coreStorage createVolume (UUID) jhfs+ "Mac HD" 990g"
I get a error "-69780: Unable to create a new CoreStorage Logical Volume"
After that, my SSD drive disappears and I can no longer even boot from my USB stick! The only way to recover is to take out the hard drives and reformat them in another computer! Ugh!
What am I doing wrong?
Are you sure the SSD and HDD are disk0 and disk1? from what you say in the end it seems the USB stick is one of those.
I'm positive. Once I remove the drives and use disk utility to "fix" them on another Mac, the USB drive boots perfectly.
Maybe the correct is:
"Diskutil coreStorage createVolume (UUID) jhfs+ Mac HD 990g"
When Disk Utility "fixes" them they are Logical Volumes and not Physical Disks.I think that you have to delete the Logical Volumes before you create a new Group.And if you type in Terminal :diskutil cs list you'll see Logical Volumes and not normal disks
This is normal
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This looks like a really great option for users, so far I've been really happy with the performance.
But given the choice I'd prefer the option to do something similar but with all data kept on the HD and the SSD just used as a buffer. In other words, instead of moving data to SSD, just copy it there and reference it, but leave it on the HD as well in case of SSD failure.
Anyone know if CoreStorage offers an option that works that way?
But given the choice I'd prefer the option to do something similar but with all data kept on the HD and the SSD just used as a buffer. In other words, instead of moving data to SSD, just copy it there and reference it, but leave it on the HD as well in case of SSD failure.
Anyone know if CoreStorage offers an option that works that way?
This is where your good backup strategy would come into play.
I think if either the SSD or HD were to fail, the joined "Fusion" array would be toast, and you would have to restore from your backup. So having a mirrored copy of the SSD on the HD wouldn't gain you anything as you would be unable to access it as a standalone volume. Attempting to revert the drive back to a standard volume would probably delete any data it contained.
There would also be diminishing returns on a mirrored scheme as the SSD approaches the HD in terms of size. If you had a 512 GB SSD and a 750 GB HD, you would realize very little storage gain from the HD ... only 250 GB of additional space.
But then why is it not working? I'm still getting this same error and disk utility is unable to erase or partition because the volume is "locked". Is it because I'm using the Momentus XT or a cheap eBay optical bay? I've tried multiple times and always get an error and an unbolt able system. I really wanted to get this working and I believe I'm doing everything correctly, but I've now tried at least 5 times and am about ready to give up.
I tried it again and it seemed to work, but starting disk utility caused the SBOD. Subsequently, as before, I can't even boot the USB installer until I remove the drives and reformat them on my wife's computer. So I can't get into terminal for the output. Seems like something is terribly wrong that fusing the drives causes my system to not boot from my USB flash drive (I get the SBOD).
I'm going to give up. If this unsupported configuration is so unstable on my system, I think I won't tempt fate and will go ahead with plan B, keeping my main apps and OS on the SSD and photo library, etc on the second drive. I'm very disappointed, but I've now done this multiple times exactly as instructed and it is just not working.
Is there a "safe boot" USB option so I CAN get into terminal?
This is where your good backup strategy would come into play.
I think if either the SSD or HD were to fail, the joined "Fusion" array would be toast[/B], and you would have to restore from your backup. So having a mirrored copy of the SSD on the HD wouldn't gain you anything as you would be unable to access it as a standalone volume. Attempting to revert the drive back to a standard volume would probably delete any data it contained.
There would also be diminishing returns on a mirrored scheme as the SSD approaches the HD in terms of size. If you had a 512 GB SSD and a 750 GB HD, you would realize very little storage gain from the HD ... only 250 GB of additional space.
Of course everything should always be backed up. With the format described here, yes, losing either would take down the whole volume. I'm asking if there's an alternative way that would leave a copy of everything on the HD and still work in the case of SSD failure. I'm not thinking it of a substitute for a backup, but as an extra layer of redundancy, as an additional backup and one that would be very quick to restore. That possibility may not exist, if that's the case I'd love to see Apple add the option in the future.
And you're right about diminishing returns but either way I think it kind of defeats the whole purpose of doing a fusion drive if the SSD is really big and the HD really small. The whole point is to go with a relatively small SSD and relatively big HD.
Maybe it doesn't like the 990g number? You could try substituting 100% instead.
I suppose that you could do it manually by creating a partition using BootCamp which will make a bootable partition on your hard disk. Then install OS X on that partition as an alternative boot device in case of failure (assuming it wasn't the hard disk that failed). Of course, it wouldn't maintain the dynamic contents of the SSD, but would get you going again quickly.
I always keep a really small thumb drive (flat chip like Apple briefly used with the MB Air) with a bootable OS X system with my traveling laptop just-in-case!
I tried it again and got the same errors. Here's my output attached.
Attachments
ok now type
diskutil cs delete (Volume ID)
where(Volume ID)=25C10619.....
to start from the beginning
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Thanks, but it won't boot again to the flash USB installer. I get the apple logo and then the circle with the slash through it. I can't get back into terminal since I shut the computer off. I'm used to building hackintoshes, this should not be so hard. Maybe there's a reason Apple hasn't enabled it for all? Maybe it's flaky on some systems?
Maybe...
but you have 2 Logical Volumes (The SSD status missing) and I think that the Disk Utility can't partition the disks because they are Logical Volumes....
Maybe you have to delete the Logical volumes in other computer but as they are i don't think you can work
Unfortunately, that is a weakness of the "Fusion" drive system, even though it is composed of 2 physical drives, it has now become a single logical drive, the contents of which is constantly changing between the 2 physical drives. You no longer have the visibility of either drive individually.
If one drive fails, the contents and state of the other drive is unknown, as is/was the failed drive.
What you are describing seems to be a RAID-1 mirrored array of the SSD and a similar sized partition on the hard disk ... that then joined into a "Fusion" array with the remainder of the hard disk. That would probably lose most of the speed advantage of the SSD, but would always have a working copy of it.
Interesting concept however ...
... perhaps others will join in with additional ideas?
btw: I have had 2 SSD drives fail (early ones ... no failures since) so I don't entirely trust them. On my other computers, where I have separate SSD and hard disk drives and maintain the contents manually, I often do have the OS X system mirrored on the hard drive so I can boot from it as well (if I have the capacity to spare). However, since the SSD contents are relatively constant, it is easier to maintain a "hot spare" on the hard disk with conventional tools (CCC).
-howard
Yeah, the 2 logical volumes were created by formatting in terminal which ended in the aforementioned error.