SSD, TRIM, and Yosemite

Most SSDs can manage their storage internally these days without needing TRIM.

Given that enabling TRIM in Yosemite requires you to disable the checking of signatures on kernel extensions, it's a significant security compromise.

Here's what I suggest: Just install the SSD and forget about TRIM. Maybe run a benchmark on your new storage. After 6 months, run the benchmark again, and see how it performs. If it's more than 20% slower, then evaluate your options. I suspect you won't notice a slowdown.

Hi Apple Bytes77,

In our organisation we also have a couple of 2010MBP's that we have upgraded, some quite some time ago and some more recently. While we have no experience with the 850, we have a lot of experience with Crucial and some other, amongst which some lesser Samsung SSD models. Our current oldest 2.5" SSD (Crucial) is now approaching four years and still performing impeccable. Running DriveX also indicates that it is still very healthy.

We have run Trim on it in the past, but since the advent of the Beta program for Yosemite it has been Trimfree. We have another of the same model still with Mavericks on it and it is still 'Trimmed'. I have not observed any noticeable difference between them up to now.

Yosemite will also create a Core Storage Logical Volume on the disk which will manage the disk usage largely on its own.

I can vouch for the reliability of the Crucial product, since Snow Leopard all the way through to Yosemite.

Have fun

Leo

There have been some serious issues reported regarding the use of TRIM under Yosemite. It would be a good idea to not use TRIM. As has been stated elsewhere modern SSDs really don't require TRIM all that much due to improved designs from a couple of years ago.

You may find that Samsung's latest 850 model may or may not work in your model. Be sure to use a vendor with a good return policy just in case. The Samsung 840 models, on the other hand, should be fine. I'm quite partial to some OCZ models. They seem pretty compatible and trouble-free.

There is a lot of debate on whether or not you actually need TRIM, especially now when a lot of the good SSDs have decent garbage management built in. You will get people to argue both ways. I would go with getting a good drive and not worry about it. If you do decide to use TRIM, be sure to disable it before performing any OS software updates. I've seen many people have problems afterwards of not being able to boot up because of it.

Many people from what I see really like that Samsung. It's suppose to have decent garbage management built in. But I'm not sure if they are putting it in older equipment or with the newer capable of SATA III speed. I, like you only have SATA II on my computer. I decided to go with the OWC 3G SSD because of it. With OWC, they warn you not to put the 6G SSD in certain models with SATA II because it will actually only operate at SATA I speed of 1.5G instead of 3G. You would have to check your model at their website to see how it applies to your computer. Maybe that warning only applies to their drives. I'm not sure how a 6G SSD of another brand would work with SATA II with the speed issue. I would investigate that beforehand or maybe someone with first hand experience will comment on this.

They also advise against enabling TRIM with their drives. They claim their built in software is sufficient to take care of and manage the drive. Their site doesn't say TRIM will hurt their drives, it just says it doesn't need it and doesn't recommend it.

I've been using mine for several months now and love it. I know my speed is limited by my hardware, but it is definitely faster and well worth the expense in my opinion. After the initial installation and given a period of time for the drive to settle in with a good bit of use, I check the speeds on occasion. Each test over several months produce the same results so far. Compared with my original HD, my sustained Read/Write speeds have doubled. Random Read/Write speeds as much as 100 times faster than original drive. My computer boots up in about 20 seconds as opposed to about 80 seconds before.

I also installed the same drive in my son's 2008 MacBook Pro. His only had SATA II capabilities also. His original drive was much slower (5400 rpm) than my iMacs original drive. His speed increase was much greater due to that fact. About 3+ times faster than before on sustained Read/Write.

You won't be disappointed in the upgrade. It will bring new life to your computer.

Note that I only have experience with this one model. So read and evaluate the reviews of others who may have used different brands and may have better insight.

As you've seen, there's a lot of disagreement about the importance of TRIM and a fair amount of misunderstanding about TRIM vs Garbage Collection. Probably the most revealing discussion and test results I've seen on the subject are in this review. The narrative is interesting, including the comments in the last paragraph on that page, but a close, careful look at the graphs shows a far more revealing story about what a difference TRIM makes. The position of Crucial on the subject is also interesting.

SSD firmware updates are often a fact of life for new SSD's. I've seen complaints about Samsung's firmware update process and a look at the PDF instructions on their website, especially the part about possibly needing a "Power Cycle," suggests why.

As far as being on a tight budget goes, you might check out this deal from OWC. I've been using one for a year without issue, and it's an SATA III drive on an SATA II bus with a 3Gb negotiated link speed, albeit in a Mac Pro, not a MacBook Pro.

That note about the the speed issue is plainly stated when looking at their Mercury 6g SSD. It will show the list of models in the compatablilty notes. Only certain models are affected and you would have to get your computer model identifier and check it at their site.

I have no idea about that issue with other brands. They don't show anything when looking at the crucial SSD at the OWC site, but then again they don't say what it is compatible with. When you check at the crucial site, you can check what drives are compatible with you computer. But they state anything about the speed issue, so it may be OK. As FatMac points out, he is using a Crucial 6g SSD on a sata II bus. But he may also have a model not affected by this issue. I really don't know the correct answer except check out the compatability of whatever brand you buy and maybe check with their tech support on that.

For the transfer cable issue, that would depend on how you plan to transfer your drive and what you plan to transfer the data to. If you have an external drive, then just clone your boot drive to it and verify you can boot from it. You can then install the new drive and clone back to it from the external drive. You need to provide more info on how you plan to do this.

You don't need to buy any software to clone with. CCC is free to download and is donation ware. SuperDuper has a trail version which I think is bootable without buying. You mac has built in software to do this. Use disk utility's Restore function to restore one drive to another. When I installed my SSD, I used disk utility for copying my original drive to the SSD with no problems.

As far as price, Crucial probably the cheapest. I've seen some comment on good results from OCZ drives, but I don't know the prices. Samsung is a bit more expensive.

Here is an article from the OWC blog on TRIM:

http://blog.macsales.com/21641-with-an-owc-ssd-theres-no-need-for-trim

I found this question and answer at the bottom of the article about the speed issue. In the answer, it's noted that the limitation exists on all 6G drives on his computer. Does that mean all 6g drives or just their Mercury 6g drives? I don't know the answer to that, but from what it implies, it means any 6g drives.

Marko.P @ 4:42 am on December 26, 2014

As I finally installed OS X Yosemite on OWC SSD and I tested it for speed…
But what should be the speed (read/write) on my new SSD, because I tested it yesterday (with Blackmagic Disk Speed Test) and it shows only write: 110MB read: 135MB is it possible???

OWC Ben M @ 10:47 am on December 29, 2014
Those speeds are normal for a 6G SSD in your iMac. As mentioned in the compatibility section of the 240GB Mercury Electra 6G SSD, A 6G SSD will only run at SATA 1.0 (1.5G aka 150MB/s) on certain Macs. This is due to the Nvidia SATA controller found in these computers not being able to properly down clock a SATA 3.0 6G SSD to the expected SATA 2.0 3G your computer is capable of. This limitation exists on all 6G drives on your computer.

As I said, check your model identifier and check to see if it is affected. Not all models are affected by this. If your computer is one of the affected models, then you will have to decide on taking a chance on other 6g SSD brands. They may be fine, but I just don't know.

Please remember that I'm not trying to put down other brands or steer you to an OWC. It's what I have and I can't comment on other brands because I've not tried any.