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Applelip
Dec 25, 2011, 01:00 PM
I was wondering should I install an internal SSD in my 27' Imac Spring 2011, or purchase a Lacie little big disk external SSD and boot Lion from thunderbolt? The cost of doing each option is about the same price, because I can, but won't install the SSD myself. Which option is faster? Will I get the same speeds? Sorry for all the questions. googled this all night, and could not find anyone that has done this yet. Thanks in advance.



wrinkster22
Dec 25, 2011, 06:19 PM
you have stated that...
I am not sure about speeds, But I would go internal.
By getting apple to put the SSD in you get warranty and peace of mine. It also looks nicer.
If you use the Lacie TB drive you void the warranty by opening that, will have to do a lot of work, may get dud SSD's or enclosures, and it looks crappy.

thekev
Dec 25, 2011, 06:27 PM
External SSDs are beyond pointless. Lacie does not make a durable product for one. Thunderbolt also adds a lot of latency. External SSD boot shouldn't even be one of your options for consideration. Either can end up with issues or drive failure (internal or external). I just don't think you realize how bad of an idea this is. Even if sustained throughput was higher via raided SSDs, it would still be a terrible idea.

Edit: Also do not bump your own thread several times in one day.

Applelip
Dec 25, 2011, 07:07 PM
Wirelessly posted (Mozilla/5.0 (iPhone; CPU iPhone OS 5_0_1 like Mac OS X) AppleWebKit/534.46 (KHTML, like Gecko) Version/5.1 Mobile/9A405 Safari/7534.48.3)

Sorry I went back on my browser and it re-sent my last message. I got a new 27" iMac as a gift from my wife, and she did not choose the SSD option. LaCie makes the first SSD external thunderbolt drive. There is no need for modding. 10Gbits for the thunderbolt versus, 6Gigbits on Sata. SSD speeds and compacity are
Only getting faster and bigger.

Icaras
Dec 25, 2011, 07:43 PM
Thunderbolt also adds a lot of latency

Uh, what?

AppleNewton
Dec 25, 2011, 07:48 PM
Wirelessly posted (Mozilla/5.0 (iPhone; CPU iPhone OS 5_0_1 like Mac OS X) AppleWebKit/534.46 (KHTML, like Gecko) Version/5.1 Mobile/9A405 Safari/7534.48.3)

Sorry I went back on my browser and it re-sent my last message. I got a new 27" iMac as a gift from my wife, and she did not choose the SSD option. LaCie makes the first SSD external thunderbolt drive. There is no need for modding. 10Gbits for the thunderbolt versus, 6Gigbits on Sata. SSD speeds and compacity are
Only getting faster and bigger.

But SSDs are not going to run at 10Gbps since they're either at 3Gbps or 6Gbps

PhoenixMac
Dec 25, 2011, 09:02 PM
it depends if the TB SSD can be booted from, I remember people asking about it but I didn't see an answer if it could or not.

If the TB SSD can be booted from I would prefer TB SSD compared to internal as when swapping computers I would keep it consistent with the same boot drive whether going to work and using the macbook pro or coming home and using the iMac.

Swift Sketcher
Dec 25, 2011, 11:27 PM
External SSDs are beyond pointless. Lacie does not make a durable product for one. Thunderbolt also adds a lot of latency. External SSD boot shouldn't even be one of your options for consideration. Either can end up with issues or drive failure (internal or external). I just don't think you realize how bad of an idea this is. Even if sustained throughput was higher via raided SSDs, it would still be a terrible idea.

Edit: Also do not bump your own thread several times in one day.

Uhhh... What!?

1) I've had a Lacie Rugged External HDD for 2 years and a half, works like new.

2) Thunderbolt connections are extremely fast and even the fastest SSD drives don't even come close to hitting the ceiling on their TB transfer speeds.

3) SSD drives have no moving parts, thus rate of failure is severely reduced.


edit: I think I just fell for a troll post. I mean it has to be a troll post anyway :cool:

Applelip
Dec 26, 2011, 12:59 AM
But SSDs are not going to run at 10Gbps since they're either at 3Gbps or 6Gbps


Do you understand that only the SATA interface is limited to 6Gbps, and not the SSD technology itself?

MythicFrost
Dec 26, 2011, 01:26 AM
What's the latency like over Thunderbolt? Yeah, it's fine for huge sequential read/write, but what about random I/O?

Oh, and just so you know: if you intend to install Windows, it can't be done on an external disk.

thekev
Dec 26, 2011, 04:18 AM
But SSDs are not going to run at 10Gbps since they're either at 3Gbps or 6Gbps

I agree with you on this, but I'm going to add something small. 10Gbps is a theoretical maximum in each direction. It's not looking quite attainable yet even in lab settings. It's just a hard cap on bandwidth. Even with perfect efficiency you can't physically surpass that in its current generation. I think it was anandtech that tested it and found a drop in performance with more devices attached. Random reads/writes on thunderbolt devices are significantly slower as well due to latency factor. This is one of the reasons I said don't boot from it. It seems way silly paying more for something with those issues.

Uhhh... What!?

1) I've had a Lacie Rugged External HDD for 2 years and a half, works like new.

2) Thunderbolt connections are extremely fast and even the fastest SSD drives don't even come close to hitting the ceiling on their TB transfer speeds.

3) SSD drives have no moving parts, thus rate of failure is severely reduced.


edit: I think I just fell for a troll post. I mean it has to be a troll post anyway :cool:

It wasn't a troll post you silly person. Since you think it was, I'll give you appropriate details and correct one of your mistakes :).

SSDs still fail. They do not fail from mechanical wear, but that's only one issue with drives in general. The memory itself does fail (an SSD has a certain amount of redundancy built in) but it's more common to see things like controller failures. The most recent of these issues was the sandforce controller issue in the SATA III SSDs. It's really a myth that they have a really low failure rate. Plenty of them die prematurely.

Things lasting a long time would be a new thing for Lacie at least under heavy use. I've come across more dead lacie firewire drive than any other brand, and I've had to crack open a few of those cases to attempt to get data for people. Basically their firewire drives historically have run extremely hot, but it's usually the connective electronics that burn out. The rugged drives are a bit different. They're not something you keep turned on all the time as storage. The OP wanted to boot from these via thunderbolt, meaning you are in fact adding latency to a boot drive. This is a very bad thing. If you're looking for simple storage drives, you'd get way better capacity from HDDs. Either can die. Neither is acceptable without backups. Arguing moving parts vs lack of moving parts is pointless. Plenty of things with non mobile parts die (fanless gpus, logic boards, ram, flash cards, etc.).

Regarding thunderbolt speed saturation, Intel has reported up to roughly 850MB/s upstream in their labs. The real bandwidth depends on how many devices you're hooking up. Even with a display, real world performance has dropped. Expect a real ceiling of more like 650MB/s meaning roughly 1 Raid 0 SSD setup. I believe one of the little big disks is set up this way. In any event external boot drives in general are a dumb idea.

I'm not trolling you here. Feel free to respond further, but one internally mounted disk is the best thing to boot from in any case, and the lacie little big disks have never been made from high quality hardware. Firewire drives in general are made on tight margins. With the thunderbolt stuff I think they're trying to offset the cost of development with a high price tag. It may drop off significantly with Windows side adoption next year.

leman
Dec 26, 2011, 07:49 AM
@thekev: I strongly disagree. I see no reason why external boot drive should be less viable or practical than an internal boot drive, given that the TB-latency is more or less on par with that of the regular PCI Express. I don't see much point in RAID-0-ing SSD drives (any practical performance benefit is moot, who needs high sustained speeds anyway? Its random access which is important)...

However, IMHO the best feature of an SSD is its naturally low latency and thats what makes SSD a nice combination with a TB interface. I know I will be running from an external SSD as soon as affordable enclosures start appearing...

philipma1957
Dec 26, 2011, 08:15 AM
sorry I missed this post op here is what you can do with a lacie


note this is no longer for sale but has just about all the info you need.

http://www.ebay.com/itm/150704690334?ssPageName=STRK:MEUSX:IT&_trksid=p3984.m1560.l2649#ht_3084wt_1131


here is my mac rumors thread on it

http://forums.macrumors.com/showthread.php?t=1280118

As far as I know I am the only person that has done this and posted and no one else is qualified to tell you what to expect from it. It works fine and the lacie is fine and it can work fanless. I like it so much that when the item did not sell on ebay I kept it. In fact I am using it right now.


I really advise samsung ssd's if you do this. as they pull the least power. each drive will max a Sata II so samsung series 470 which are sata II are fine.

you can run them as raid0 for max speed

raid1 for safe but slow each drive will max as a Sata II due to the internal bridge

and even jbod. In fact if you use your iMac for business and run an internal ssd you risk it dying and being stuck. if you use a lacie and make a back up copy on the internal and the lacie dies you can use the internal hdd to run your work. The power supply is so so but I gave a link on my thread for a perfectly fine power supply on ebay. Same connector and made by the same power supply company.

Applelip
Dec 26, 2011, 01:25 PM
sorry I missed this post op here is what you can do with a lacie


note this is no longer for sale but has just about all the info you need.

http://www.ebay.com/itm/150704690334?ssPageName=STRK:MEUSX:IT&_trksid=p3984.m1560.l2649#ht_3084wt_1131


here is my mac rumors thread on it

http://forums.macrumors.com/showthread.php?t=1280118

As far as I know I am the only person that has done this and posted and no one else is qualified to tell you what to expect from it. It works fine and the lacie is fine and it can work fanless. I like it so much that when the item did not sell on ebay I kept it. In fact I am using it right now.


I really advise samsung ssd's if you do this. as they pull the least power. each drive will max a Sata II so samsung series 470 which are sata II are fine.

you can run them as raid0 for max speed

raid1 for safe but slow each drive will max as a Sata II due to the internal bridge

and even jbod. In fact if you use your iMac for business and run an internal ssd you risk it dying and being stuck. if you use a lacie and make a back up copy on the internal and the lacie dies you can use the internal hdd to run your work. The power supply is so so but I gave a link on my thread for a perfectly fine power supply on ebay. Same connector and made by the same power supply company.

Thanks, I did not want to void my iMac warranty. I knew that the external TB drive was just as fast, and I will have the option in the future to upgrade my SSD's when the drive get bigger and cheaper. I will just run windows on the 7200rpm HDD for now.

philipma1957
Dec 26, 2011, 02:27 PM
Thanks, I did not want to void my iMac warranty. I knew that the external TB drive was just as fast, and I will have the option in the future to upgrade my SSD's when the drive get bigger and cheaper. I will just run windows on the 7200rpm HDD for now.

i run windows on my mini server internal hdd and osx on the lacie

thekev
Dec 26, 2011, 04:23 PM
@thekev: I strongly disagree. I see no reason why external boot drive should be less viable or practical than an internal boot drive, given that the TB-latency is more or less on par with that of the regular PCI Express. I don't see much point in RAID-0-ing SSD drives (any practical performance benefit is moot, who needs high sustained speeds anyway? Its random access which is important)...

However, IMHO the best feature of an SSD is its naturally low latency and thats what makes SSD a nice combination with a TB interface. I know I will be running from an external SSD as soon as affordable enclosures start appearing...

Quality one might make it more worthwhile, but you'd still get better capacity from Raided HDDs if you're going with something that is set up as a raid (like some of the Little Big Disks). Lacie's stuff really isn't made for a high duty cycle as I mentioned. It's designed for light use. The guys that keep them on all the time are the ones who frequently see them die just outside the warranty.

Random is important for boot, memory paging, etc. Sustained can affect things like save times on large files, so yeah it depends on what you are doing. I haven't checked Apple's pricing on upgrades at time of purchase, but I do understand the OP not wanting to open a closed system. The imac design is kind of silly. It should have a removable backplate of some kind to facilitate replacing a hard drive (that and the stupid heat sensor thing should go away). The thing is that hard drives are inherently one of the least reliable components, which is why I'd hate to own a machine where I couldn't swap it at will. I still stand by what I said, the Lacie isn't appropriate for this kind of use. I'll see if I can find the info on TB. I do recall it having much lower random access performance.

smphoto74
May 1, 2012, 03:51 AM
External SSDs are beyond pointless. Lacie does not make a durable product for one. Thunderbolt also adds a lot of latency. External SSD boot shouldn't even be one of your options for consideration. Either can end up with issues or drive failure (internal or external). I just don't think you realize how bad of an idea this is. Even if sustained throughput was higher via raided SSDs, it would still be a terrible idea.

Edit: Also do not bump your own thread several times in one day.

I got the LaCie 2TB LBD and replaced the HD's with 2 Crucial M4 128GB SSD's and put them in Raid 0 and my iMac boots in 15 seconds so I would have to somewhat disagree with you. Putting just 1 SSD in the Pegasus R4 unit got me decent speeds but 45 second boot times so not all TB devices work fast for booting(not sure why). Pegasus R4 with 4TB(raid 0) gets me 500mbps write and read. I did copy a 5.79GB file from the LBD to the R4 and it took 11.9 seconds. That is fast and totally worth the risk(my system is backed up on 3 drives daily)