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CESNET Author

Level 1

58 points

Hard Drive replacement with SSD

Hello There

I want to replace my HHDD on my Macbook pro Mid2010 with a Samsung SSD Evo 850 1TB.

I have some questions.

- Is the Samsung Evo 850 1TB compatible?

- How should I proceed. I mean not the physical part, for which I found lot of videos, but the software one. I'm regularly backing up with Time machine, but do I need to make startup disk? I guess yes but How? DVD or USB drive?

- after doing the SO fresh install, then do you recommend to restore from the Time Machine or to reinstall all additionnal SW manually and then get the data from the Time machine (pictures, music, docs, etc...). this would be slower, so the question is, is it worth the time lost.

many thanks in advance.

Regards.

sorry for my english, I'm from Spain

MacBook Pro (13-inch Mid 2010), OS X Yosemite (10.10), HD Momentus XT 750GB

Posted on Jul 28, 2015 3:20 AM

Best reply

Lexiepex

Level 6

14,102 points

Posted on Jul 28, 2015 3:55 AM

There are enough threads about this here.

BUT: news is that Samsung has acknowledged the SSD 840EVO, 850EVO and their Pro sisters, are having a data loss problem, caused by a design problem. A Firmware is on the way, but will not "repair" this fault but does only a workaround by having the data rewritten every few months (which slows the SSD write speed, and which shortens its lifetime. It does not guarantee that the data loss will not happen after the firmware update.

On all non-Apple SSDs: do not install the Trim command, because that also can corrupt data.

More info on both above:

http://www.extremetech.com/gaming/203449-new-samsung-840-evo-firmware-will-add-p eriodic-refresh-capability

Lex

View in context

25 replies

Jul 29, 2015 10:09 AM in response to Lexiepex

Do you not understand? The issue was seen in Linux only, in RAID, in Server environment, using EXT4 format, under heavy IO.

The issue has not been seen in MAC OSX.

Lexiepex

Level 6

14,102 points

Jul 29, 2015 10:17 AM in response to sustainednotburst

You don't seem to read very well: It is OWC who always tells that you "do not need" Trim. But as I said it is depending on the Controllers not the Brands. Crucial uses the Marvell controller.

Since you are the only one here who wants to be right (except myself ofcourse) we better close this discussion and read again about what a lot of testers have published.

Lexiepex

Level 6

14,102 points

Jul 29, 2015 10:19 AM in response to sustainednotburst

in Linux only

OSX is a (very nice) UI on Linux.

Jul 29, 2015 10:32 AM in response to Lexiepex

OSX is different from linux.

Mac OS is based on a BSD code base, while Linux is an independent development of a unix-like system. This means that these systems are similar, but not binary compatible.

Furthermore, Mac OS has lots of applications that are not open source and are build on libraries that are not open source. Because of this reason, it is not possible to port those applications to run on Linux without being the copyright owner of those applications and libraries.

Please provide links to these testers saying that TRIM causes Data Loss, cause, unlike you, i've provided sources to back up my statements.

Csound1

Level 9

59,973 points

Jul 29, 2015 10:36 AM in response to sustainednotburst

Try a little googling, here's one to start with.

https://www.cindori.org/forums/topic/data-loss-due-to-defective-trim-implementat ion-in-samsung-ssds/

Jul 29, 2015 10:41 AM in response to Csound1

Did you read it? They directly reference the Algolia blog, which if you read my earlier posts, Algolia found out that the issue was caused by their Linux Kernal, not the SSD.

From that link you provided "The warning Apple issues (in reference to the new TRIMFORCE) is for early SSDs which had a dodgy non-queued trim implementation."

Csound1

Level 9

59,973 points

Jul 29, 2015 11:14 AM in response to sustainednotburst

You're the one asking for links, and I don't care what you may think beyond that.

Have a good one.

Jul 29, 2015 11:52 AM in response to Csound1

I asked for links for him to prove his statements. The link you provided did nothing.

And what i've written so far is not what i think, its cold hard facts. There is no Data Loss with TRIM on newer (last 3-4 years) SSDs, since the OP was thinking of getting an 850 EVO 1TB.

Lexiepex

Level 6

14,102 points

Jul 29, 2015 12:09 PM in response to sustainednotburst

My last note: I can provide enough links for analysis, but think that you already know the conclusions in there.

The "refreshing" has to do with the structure TLC, a new and wonderful step forward by Samsung.

The Trim has to do with the controllers, especially the queued trim command.

I wonder how you measure the GarbageControl and Trim effects: how can you be sure that there is no bit or byte corruption. Do you test all writes and files?

It looks as if I have a question here, but this remark is not meant as a question, but as an impuls to think it through.

Jul 29, 2015 12:24 PM in response to Lexiepex

Only Linux utilizeS Queued TRIM..so far, but there haven't been any rumblings or talk of Windows 10 or El Capitan using Queued TRIM.

The refreshing doesn't constantly run. It only runs as necessary and only if the SSD is idle, so even if it runs 1 or 2 times a year, it would be little to no impact on the life of the drive.

About looking for corruption with TRIM and GC. You can check file or data integrity by using the MD5 hash /checksum. http://osxdaily.com/2009/10/13/check-md5-hash-on-your-mac/

Hard Drive replacement with SSD