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will a samsung 850 pro ssd work with yosemite?

Christopher Breen has an article today in Macworld explaining that most SSDs will not work with Yosemite. To paraphrase Mr. Breen, Apple's TRIM technology doesn't work with third party SSDs, and, while you could use Trim Enabler to make TRIM work with your drive in Mavericks, Trim Enabler modifies kext files and Yosemite will not run with modified kext files. The only workaround is to globally disable kext signing, which is not recommended for security reasons. Has anyone had any experience with this issue? I just purchased a third party SSD for my MBP. Thank you for any input.


Cheers, Peter

Posted on Nov 19, 2014 12:47 PM

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Posted on Nov 19, 2014 5:45 PM

Pram wrote:


Christopher Breen has an article today in Macworld explaining that most SSDs will not work with Yosemite.

That's not what it says. SSDs will work with Yosemite, the only thing that won't work is enabling third-party TRIM support. The SSD will boot and the SSD will work and it will be fast; having TRIM enabled is not even remotely a requirement. TRIM is just a housekeeping routine that is generally thought to be desired, but there's even debate on that.


The part of the Macworld article about not booting should only happen if you 1) enabled TRIM, 2) disabled kext signing, and 3) reset NVRAM, which re-enables kext signing and therefore blocks access to the hard drive you need to boot from. But if you didn't do 1-3 your Mac will boot into Yosemite just fine.


Some SSD brands do not require TRIM and some like OWC don't even recommend it because their SSDs have their own similar routines. I have a Samsung 840 and it works fine in Yosemite but I have not attempted to enable TRIM. I am not sure what the long term impact of that is, and I'm going to post a separate question regarding whether Disk Utility performs a trim when you Repair Disk because I read that somewhere.


In the end, the questions are: Does my SSD need TRIM, and if it does, how bad is it to run it in Yosemite without TRIM enabled? I am trying to find out the answer to the second question to know if not enabling TRIM is going to cause any more than minor problems down the road.

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Nov 19, 2014 5:45 PM in response to Pram

Pram wrote:


Christopher Breen has an article today in Macworld explaining that most SSDs will not work with Yosemite.

That's not what it says. SSDs will work with Yosemite, the only thing that won't work is enabling third-party TRIM support. The SSD will boot and the SSD will work and it will be fast; having TRIM enabled is not even remotely a requirement. TRIM is just a housekeeping routine that is generally thought to be desired, but there's even debate on that.


The part of the Macworld article about not booting should only happen if you 1) enabled TRIM, 2) disabled kext signing, and 3) reset NVRAM, which re-enables kext signing and therefore blocks access to the hard drive you need to boot from. But if you didn't do 1-3 your Mac will boot into Yosemite just fine.


Some SSD brands do not require TRIM and some like OWC don't even recommend it because their SSDs have their own similar routines. I have a Samsung 840 and it works fine in Yosemite but I have not attempted to enable TRIM. I am not sure what the long term impact of that is, and I'm going to post a separate question regarding whether Disk Utility performs a trim when you Repair Disk because I read that somewhere.


In the end, the questions are: Does my SSD need TRIM, and if it does, how bad is it to run it in Yosemite without TRIM enabled? I am trying to find out the answer to the second question to know if not enabling TRIM is going to cause any more than minor problems down the road.

Nov 19, 2014 5:57 PM in response to Network 23

Hello Network 23,


Thank you very much for your reply. So the pertinent sentence in the article is, "...you can boot from the SSD, but it won't run with the benefit of TRIM." For the less than average user like myself this shouldn't be a problem. I would very much like to hear whatever you find out about your second question.


Cheers, Peter

Dec 21, 2014 7:04 AM in response to Pram

I recently replaced my hard drive with a SanDisk SSD. At the same time I removed the optical drive because I felt it was holding down the SATA speed, I was right. Here are some stats from my system:


Results372.27
System Info
Xbench Version1.3
System Version10.10.1 (14B25)
Physical RAM8192 MB
ModelMacBookPro5,3
Drive TypeSanDisk SDSSDXPS480G
Disk Test372.27
Sequential236.05
Uncached Write362.92222.83 MB/sec [4K blocks]
Uncached Write291.38164.86 MB/sec [256K blocks]
Uncached Read120.2735.20 MB/sec [4K blocks]
Uncached Read409.21205.66 MB/sec [256K blocks]
Random880.18
Uncached Write1265.59133.98 MB/sec [4K blocks]
Uncached Write542.25173.59 MB/sec [256K blocks]
Uncached Read1628.3911.54 MB/sec [4K blocks]
Uncached Read771.54

143.16 MB/sec [256K blocks]


Vendor:NVidia
Product:MCP79 AHCI
Link Speed:3 Gigabit
Negotiated Link Speed:3 Gigabit
Physical Interconnect:SATA
Description:AHCI Version 1.20 Supported



SanDisk SDSSDXPS480G:



Capacity:480.1 GB (480,103,981,056 bytes)
Model:SanDisk SDSSDXPS480G
Revision:X21100RL
Serial Number:143631400200
Native Command Queuing:Yes
Queue Depth:32
Removable Media:No
Detachable Drive:No
BSD Name:disk0
Medium Type:Solid State
TRIM Support:No
Partition Map Type:GPT (GUID Partition Table)
S.M.A.R.T. status:Verified

Volumes:

EFI:

Capacity:209.7 MB (209,715,200 bytes)
BSD Name:disk0s1
Content:EFI
Volume UUID:0E239BC6-F960-3107-89CF-1C97F78BB46B

SanDisk:

Capacity:479.11 GB (479,110,004,736 bytes)
Available:347.42 GB (347,417,059,328 bytes)
Writable:Yes
File System:Journaled HFS+
BSD Name:disk0s2
Mount Point:/
Content:Apple_HFS
Volume UUID:FA84107F-322D-37F3-BE2F-779C43F45EAB

Recovery HD:

Capacity:650 MB (650,002,432 bytes)
BSD Name:disk0s3
Content:Apple_Boot
Volume UUID:D22A1C35-6C0C-3D7E-A496-EC53E520CE58

Dec 21, 2014 8:57 AM in response to ApexRon

Just an FYI, 2 weeks ago I installed the Samsung 850 Pro SSD in my Mac Mini running Yosemite and have not experienced any problems. I have read many articles on "Trim" and in the end have decided not to install it because it disables kext signing. If you read this discussion (Does Disk Utility do TRIM for a 3rd party SSD?) you will see that you can sign on as a single user and use the command "fsck -fy" which will trim unused blocks.

Dec 29, 2014 1:51 PM in response to Thorodinsson

I too have this question - but what I want to do is to start fresh with my new SSD, and then transfer data as needed for a "clean install". I have already formatted my SSD (via an enclosure), ideally what I'd like to do, is install the OS onto the new SSD, and then simply swap it out - start up my machine and transfer needed data and apps as needed. Since it is a new drive, and this TRIM and KEXT is an issue, if I have never touched them before when it installed onto my machine, do I need to check or make sure that they are okay, and not needed to be altered.


So I guess my question would be, is there a way to go about what I want to do for a clean install onto the new SSD?


I've done many HDD swaps before, but that was when the discs from the machine were needed - now everything gets installed via internet - so its kinda new territory for me.


Thanks!

Feb 18, 2015 8:15 AM in response to Network 23

Network 23 has possibly mistakenly provided advice and information that is inaccurate.

Some SSD brands do not require TRIM and some like OWC don't even recommend it because their SSDs have their own similar routines.

Apple Should have Trim enabled (as it does with SMART and other technologies) if the device supports it regardless if Apple sells the SSD or not.

For some unpublished reason that harms customers, Apple and 3rd party vendors of SSDs are confusing the public on this issue. Including OWC by blogging that their SSDs do not require Trim.


As usual practice at OWC they circumvent the whole problem (Apple's) by either using or emulating the same vendor chipsets Apple uses and thus OSX automatically has Trim enabled by default

User uploaded file

OWC needs trim and they get it!

OWC please do not lie to me, thank you! (love their products too btw)

SSDs will work with Yosemite, the only thing that won't work is enabling third-party TRIM support. The SSD will boot and the SSD will work and it will be fast; having TRIM enabled is not even remotely a requirement. TRIM is just a housekeeping routine that is generally thought to be desired, but there's even debate on that.

There is no debate, there is FUD as written above Apple and other Vendors are misleading the public and for anyone wanting to get a clear understanding on this topic google Kent Smith of LSI


Trim is designed to interoperate with the standard Garbage Collection implemented by all vendors. An easy explanation is that Trim is the OS' side of targeting what garbage to collect. It's just that simple and it completely enhances the longevity as well as the performance for your SSD. That's why a hardware vendor like Apple has discovered a means to cripple competitor products (on their own platform for godsakes...) and thus harm you the Apple Customer.


This is truly a counterproductive move by Apple, and frankly appears to me the harbinger of more "Insanely Insane" things to come from the Company...


Good luck Guys!

Oclair


Parting thoughts....

"Keeping your SSD TRIM

A number of years ago, the storage industry got together and developed a solution between the OS and the SSD by creating a new SATA command called TRIM. It is not a command that forces the SSD to immediately erase data like some people believe. Actually the TRIM command can be thought of as a message from the OS about what previously used addresses on the SSD are no longer holding valid data. The SSD takes those addresses and updates its own internal map of its flash memory to mark those locations as invalid. With this information, the SSD no longer moves that invalid data during the GC process, eliminating wasted time rewriting invalid data to new flash pages. It also reduces the number of write cycles on the flash, increasing the SSDs endurance. Another benefit of the TRIM command is that more space is available for dynamic OP."

Feb 23, 2015 1:05 PM in response to GreyWullf

GreyWullf wrote:


you will see that you can sign on as a single user and use the command "fsck -fy" which will trim unused blocks.

I do not believe that is a substitute for enabling TRIM. From the reading I have done online, the trimming that fsck does depends on the blocks first being marked by TRIM as OK for trimming. It depends on TRIM being run continuously.


If you have not been running TRIM continuously, the blocks are not being marked as you use your computer, so when you reboot into single user mode and run fsck it may not trim much. There may be thousands of blocks needing TRIM, but because TRIM was not running, they were never marked, so fsck does not know they are there to be trimmed.


That is my understanding, if anyone has proof it is wrong I'm happy to be corrected.

Mar 25, 2015 3:13 PM in response to GreyWullf

i just bought an 500gb EVO 850 for my late 2009 Mac Mini and after

reading about the trim/kext fiasco i called Samsung and spoke

to a very knowledgable guy in tech support. he said he has

seen users that regularly delete lots of files burn up an SSD

in less than 60 days and even though they're covered under

warranty it's a huge hassle !


i don't use any peripherals that use 3rd party drivers so

kext signing shouldn't be a problem, i'll use Trim Enabler

and play it by ear. 😕

Mar 31, 2015 6:44 AM in response to Pram

Well, I packed out my Samsung SSD 850 PRO to day, and installed it into my MacBook Pro. My Macbook vill not accept it - off course, I have formatted the new drive in disk utility. Shortly after I start the install, I get the message: Yosemite cannot be installed on this computer (or something like that). I use a prepared Memory Stick for the installation...


Has anyone actually got a Samsung SSD 850 PRO up running on a Mac, Yosemite or other OS? And how did you do it?


I have tried to install Mountain Lion in stead (the MacBook is build with this OS). Here I used the recovery start up menu. But here you are met with a frustrating stop sign after boot.


As an last option I installed the Yosemite on the SSD, by connecting it to my iMac with an USB 3.0 interface. But again, the result was most disappointing. It seemed to install allright, but both the iMac og MacBook refuses to boot from the USB connected SSD.


I'm afraid, I have run out of ideas...

will a samsung 850 pro ssd work with yosemite?

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