Hard Drive replacement with SSD

There are enough threads about this here.

1

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.

2

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

1.

Do not forget that data corruption is still possible on the Samsung 840/850 SSD even after the firmware update; do not use it for business applications.

I suppose you can return the SSD and buy another brand, like Crucial. Note: all SSD also Crucial are not happy with a Trim command, whatever some app sellers may say.

2.

Easy way is:

a. make backup(s) of your system.

b. Connect the SSD outside to USB,

Start DiskUtility to formaat the SSD: Partition Tab, make 1 Partition (GUID Partition Table) with format Mac OS Extended (Journaled), make the partition a bit smaller than maximum by sliding up the bottom right angle of the partition before you start the partitioning (say 40GB), then partition /format. This is to give the GarbageCollection of the SSD controller extra space thus loose as minimum write speed as possible by GarbageCollection.

c. download CarbonCopyCloner from https://bombich.com/. You can use a trial version, although this software gives you an easy way to make a regular exact copy of your disk. Start CCC and clone your startup disk to the outside SSD, also make the RecoveryPartition when CCC ask you to do that.

d. Restart the mac, while holding the Alt(option) key, and choose the SSD. When that works correctly, shutdown again. Switch the SSD into the startup disk place. Restart the mac. Enjoy.

e. you can use the HDD as an extra outside backup disk.

Lex

1. A deal is not good when you get a product with faults.

Samsung kept this info out of the market successfully for a time. I can understand that because this unexpected flaw is in their basic production system of the memory chips inside (TLC in 840EVO and later), thus affects all their SSDs. Buyer strike would "kill" their SSD department.

2. About a bit extra space for GarbageCollection, read this article of the OWC manager (who advises against the Trim command) explaining that this makes the GarbageCollection much faster on a SSD with little free space thus keeps the write speed high in comparison with an almost full SSD:

he said:

One way to live without TRIM on OSX is just reduce the volume on the drive and leave the unallocated space...unallocated. If you have a 240GB drive I suggest removing 40GB. The drive will map this into the over provisioning and move the space in and out of use on the volume very quickly...almost faster than TRIM does.

In the Forum 22-10-2010

Also read this discussion completely:

http://www.macrumors.com/2015/07/01/os-x-trim-ssd/

Lex

As an addition: I have 6 years experience with SSDs, and several brands, and say about 20 of them. Also I have experience with Trim from the time of GrantPannell Terminal commands to get Trim (about the same time that the kid Cindori came with a faulty TrimEnabler based on these Terminal commands.

Also have experience in this SSD mix with the several SSD controller types (especially Sandforce and Marvell).

Since the GarbageCollection in the SSD controllers has advanced to a very efficient level, Trim is absolutely to avoid, as I propose already for some time.

The warning that Apple gives in the Trimforce command is real and not just marketing humbug.

Lex

Great.

1. I forgot one question: Trim is not automatically in OSX, so you do not have to disable anything. The Trim Settings command is available in 10.10.4 and will be available likewise probably in ElCapitan in the same way.

2. A clean install is indeed a good idea, but it will cost you more time. Do it and be happy.

3. I have about 25GB unallocated space normally, but of course 40GB is even better, and on a 1TB SSD it is not really cramping to do that.

4. Of course you should never use Defragmentation in a mac. And you should also avoid using speed counting apps like Blackmagic's DiskSpeedTest: These apps bring a heavy addition to the GarbageCollection.

Lex

btw thanks for your nice words 🙂

Where in the world did you get this information? Samsung never did any such thing? The Data Loss thing is from one company called Algolia which had a data loss issue with TRIM, which Tech Report found out about and reported it as if it affects anyone. In reality, Algolia worked with Samsung and both found out that the issue was caused by a timing issue in their Linux RAID setup. Samsung released a Linux kernal fix that fixed Algolia's issue.

From their blog, last updated on July 17:

"UPDATE July 17:

We have just finished a conference call with Samsung considering the failure analysis of this issue. Samsung engineering team has been able to successfully reproduce the issue with our latest provided binary.

Samsung had a concrete conclusion that the issue is not related to Samsung SSD or Algolia software but is related to the Linux kernel.

Samsung has developed a kernel patch to resolve this issue and the official statement with details will be released tomorrow, July 18 on Linux community with the Linux patch guide. Our testing code is available on GitHub.

This has been an amazing ride, thank you everyone for joining, we have arrived at the destination.

For all followers of this blogpost and all the new readers:

The discovered issue has much bigger impact than we originally expected and is not caused by Samsung SSDs, as we originally assumed.

My personal apologies to Samsung!"

None of the Samsung SSD, of which i have several, have write speed issues? The 840 EVO had a Read speed bug that affected Read speeds on data that was untouched for more than 30 days. Samsung fixed it back in April with a FW fix,and btw, it doesn't constantly rewrite the data on the drive. The new FW algorithm by itself immediately increased the read speeds back to normal on the 840 EVO mere seconds after updating the FW. If it was rewriting data, it would take a lot longer than that.

Forgot to add, You can enable TRIM through TRIMFORCE on Samsung SSDs in OSX 10.10.4. They won't have any issues.

Tested and found.

Search and read yourself, especially the refresh firmware update.

Trim: not only Samsung but most other brands' controllers have issues with Trim (a.o. Crucial).

I have an 840 EVO, i have the new FW update. Its not constantly refreshing my data. From the Pcperspective review of the new FW: http://www.pcper.com/reviews/Storage/Samsung-Magician-46-and-840-EVO-EXT0DB6Q-Fi rmware-Review-Finally-Fixed

"We did discover that updating the firmware alone was enough to get some of the performance back immediately (without the need for the advanced restoration procedure to be triggered). On the next page we will be testing this thoroughly.

Our test sample had slowed even further since the last time we tested it - nearly to the speeds we saw before performing Samsung's first attempted fix.

The above test was run immediately after the firmware update, giving the 840 EVO no time to refresh data. We see that just updating the firmware alone yields a large improvement to the reading of stale data. Apparently there is more to this update than what Samsung led on in their answers to our questions. It appears that they have tweaked their read algorithm to better adapt to cells that have drifted over time."

The refresh only runs when the system is idle and only if it detects that its necessary

Also from the end of their conclusion page: "One final note - this issue was *only* on older TLC Samsung SSDs. Your 850 EVO is not affected (it has a completely different flash architecture), and neither is your 840 Pro or 850 Pro (those use MLC flash, not TLC)"

TechReport released an update article on the "trim data loss" thing:

http://techreport.com/news/28674/samsung-says-data-eating-trim-bug-is-a-linux-ke rnel-problem

"Remember that potential TRIM bug in Samsung drives we reported on a few weeks ago? It may not be Samsung's fault, after all. Samsung and developer Algolia have been working together to try and get to the root of things, and after weeks of work, Samsung is blaming the problem on a bug in the Linux kernel"

And here's the patch info: http://www.spinics.net/lists/raid/msg49440.html

My workplace has multiple Mac Book Pros ranging from 2010 to 2012 with Samsung SSDs and we enabled Trim through TRIMFORCE when 10.10.4 came out, before that we used TRIM enabler to enable TRIM on our Macbooks ever since Mountain Lion. Never had any issues. The only time we had issues is when we had Mac Books that we forget to turn TRIM on and after a few months the SSD would start to slow down. Once we enabled TRIM, the system went back to normal.

You can not see that, so how do you know.

The refreshing is in the controller/hardware

The Trim is in the Controller/GarbageCollection timing software, not only Samsung as I explained.

Allyn from Pcper tested it thoroughly. He stated so on Overclock and also included how he tested for it. It was back in April, so i'm not about to go through hundreds of posts to find it, but from what i remember, it had to do with checking power usage, since if the controller is rewriting/refreshing data, it would use up more power than normal at idle.

You don't seem to be getting it. It was a timing issue in Linux RAID. There are no issues with TRIM in Windows or OSX. If Crucial got issues with TRIM in OSX, that explains why they tell ppl you don't need TRIM in Macs, and that's their problem, but I know for a fact that Samsung always recommends enabling TRIM on their drives, whether Windows, OSX, or Linux.

Forgot to add, Samsung FIXED the timing issue in the kernal.

Raid was never served by Trimforce, nor did it work with TrimEnabler

Maybe you should go back to Samsung, although other controllers don't do it good enough either.