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Chameleon SSD enables TRIM under Yosemite :)
- Thread starter ToroidalZeus
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Not so quick Grasshopper, you may want to read this thread:
https://forums.macrumors.com/threads/1754767/
In short, OWC is FOS.
Lou
Actually no. That thread doesn't conclusively settle the issue one way or another, but is a number of people airing their inexpert opinions. I'm not putting it down in any way, but I've been an engineer for some 30 years and know how these things go.
Basically we can't draw any conclusion.
- We don't know what OWC has implemented for their drives
- We don't know what Apple has implemented for TRIM
- We don't even know how regular drives behave in an Apple system
Basically, we don't know anything. Enabling TRIM on a regular drive may not do anything, or may even be worse - we simply have no insight into what's going on, and if we did we don't have expertise in this area.
OWC has engineers who know what they're doing (enough to develop a drive and firmware) and they're willing to bet their reputation on it, which is good enough to me. Second guessing that on a basis of no knowledge won't get anywhere.
This is not that hard to test (or experienced) by a SSD user. Just run the benchmark software before and after enable TRIM, then you will know the difference. Numbers won't lie.
Also, you don't need any expert or professional knowledge when something can solve by simple knowledge and common sense. All you need to do just study what is TRIM and how it work, then you will realise there is no modern SSD can work better without TRIM.
In fact, OWC SSD also support TRIM. If TRIM will make it perform worse or shorten it's life, then why their engineer build this function in their SSD? According to your logic, they should know what they are doing. Is that mean they intentionally implant a bomb in their product? They simply should not sell a SSD with TRIM at all? OSX won't support it natively anyway. So, why they do that? Is it because if you activate TRIM will kill the SSD, and then they can sell you another one?
Also, how about the Windows user? Once they install the OWC SSD, TRIM will start working. SSD is a SSD, the hardware won't change under different OS. And TRIM is just TRIM, just a function to improve SSD performance because of it's hardware limitation. Please don't make it too complicated. There are plenty of study to show that a OWC SSD works better with TRIM enabled, but zero evidence that TRIM can make it worse.
I am open to any discussion, however, please give evidence or at least a logical reason to support your point of view.
I did give reasons. What does testing speed tell you? It's black box testing, you don't know the reason for it. Could be TRIM, or lack of it, or could be a red herring and due to another cause. Besides which this is handwaving and misreading my post. I didn't say TRIM is bad for OWC's SSD's. I'm saying that everybody here is also handwaving and drawing conclusions that aren't warranted.
Usage patterns
It also depends on what the operating system does with blocks it has deleted. If the OS immediately reuses recently deleted blocks to store new data then TRIM is of little value. If the OS avoids recently deleted blocks for new writes then TRIM has value.
The OWC site has links to tests showing performance over time with TRIM not used. It seems to back up their conclusions that their drive being over provisioned (240GB presented on a 256GB drive) with good garbage collection algorithms results in drives that maintain performance over time, which is all the TRIM is really needed for in the first place.
In theory nobody should be seeing immediate performance advantage with TRIM, it is just for long-term performance retention and improves longevity of the unit because it results in fewer writes for garbage collection.
It also depends on what the operating system does with blocks it has deleted. If the OS immediately reuses recently deleted blocks to store new data then TRIM is of little value. If the OS avoids recently deleted blocks for new writes then TRIM has value.
The OWC site has links to tests showing performance over time with TRIM not used. It seems to back up their conclusions that their drive being over provisioned (240GB presented on a 256GB drive) with good garbage collection algorithms results in drives that maintain performance over time, which is all the TRIM is really needed for in the first place.
In theory nobody should be seeing immediate performance advantage with TRIM, it is just for long-term performance retention and improves longevity of the unit because it results in fewer writes for garbage collection.
This is incorrect. The SSD remaps the logical blocks that the OS uses to actual "sectors" on the disk. The SSD cannot rewrite an actual sector if the OS decides to write the logical block again. The SSD will remap the logical block and write it to a different actual sector. OS "reuse" patterns are irrelevant for the SSD.
Try doing a large write (say a 50 GB video file). It will be fast - until the pool of over-provisioned garbage-collected pages is exhausted - then it the write speed plummets when the writes have to wait for the garbage-collector to free up new pages.
Of course, OWC would never publish a benchmark that showed true performance on large, sustained writes.
Over-provisioning is very important. However, one big advantage to TRIM is that it basically turns all free space into over-provisioned space dynamically as the drive is used. If you're only using 120GB on that 240/256GB drive - it effectively has 155GB of over-provisioned space to get ready for the that 50 GB video file. (Note that the 240/256GB drive really has 35 GB of over-provisioned space.)
So with TRIM, you can have more usable space and the drive lasts longer.
Sounds like win-win.
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can anyone answer this? by lack of response, i'm guess that it does disable kext signing like Trim Enabler?
A Strategy for Trimming Drives under Yosemite
Keep a second boot drive under ML or Mavericks with Trim enabled.
Periodically boot from that system and perform a Repair Disk operation on your Yosemite boot SSD (and any other SSDs you may have) in Apple's Disk Utility. This will automatically Trim the disk.
Reboot into Yosemite
If you maintain adequate spare area and Trim periodically as noted, you should be able to keep your drive in optimum condition without worrying about the kext issue.
Keep a second boot drive under ML or Mavericks with Trim enabled.
Periodically boot from that system and perform a Repair Disk operation on your Yosemite boot SSD (and any other SSDs you may have) in Apple's Disk Utility. This will automatically Trim the disk.
Reboot into Yosemite
If you maintain adequate spare area and Trim periodically as noted, you should be able to keep your drive in optimum condition without worrying about the kext issue.
I should have said "almost irrelevant". A better description of the process without TRIM is that:
- OS writes short file to logical sector 100
- SSD writes the data to actual sector 3389
- OS deletes short file, OS marks logical sector 100 as "free"
- Without TRIM, SSD does not know that the OS no longer needs 3389 - it is still mapped to logical sector 100 and is considered in use
- OS creates new file on logical sector 100
- SSD writes data to actual sector 4617, remaps logical sector 100 to 4617, and marks actual sector 3389 as "free, but dirty"
With TRIM it becomes:
- OS writes short file to logical sector 100
- SSD writes the data to actual sector 3389
- OS deletes short file, OS marks logical sector 100 as "free", sends "TRIM sector 100" command to SSD
- SSD marks actual sector 3389 as "free, but dirty"
- OS creates new file on logical sector 100
- SSD writes data to actual sector 4617, remaps logical sector 100 to 4617
The advantage is that if the page containing actual sector 3389 is garbage-collected before logical sector 100 is rewritten:
- WIthout TRIM, the SSD will preserve the unused contents of actual sector 3389 by writing them to a new sector on a different page
- With TRIM, the garbage collector does not have to preserve 3389, it can simply erase it
A further consequence of TRIM is that the garbage collector has a better chance of finding a page with all or most of the sectors in the "free, but dirty" state - making erasing faster and less stressful on the SSD.
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OOPS TRIM ISSUE with Yosemite and the grey stop sign
About a week ago I updated my MacPro, 5,1_2010_6 core to Yosemite. Since then I have been getting updates to fix issues from 3rd party suppliers. Then OOPS I was installing new drivers for my GPU and things went bad. I restarted and got a grey X or stop sign half way through the process. Nothing I tried fixed the issue so before going to bed I let system X recover down-load and rebuild the system. It's running now but when I tried to reset TRIM I got this link that answered all my questions. http://www.cindori.org/trim-enabler-and-yosemite/
Bottom line don't buy stuff that apple doesn't sell or support if you want the latest system. The custom Mac Pro is not the future.
By the way if I had read the note from TRIM ENABLER instead of ignoring it it would have saved me 4 hours of trying to fix the issue.
Regards,
Bob
About a week ago I updated my MacPro, 5,1_2010_6 core to Yosemite. Since then I have been getting updates to fix issues from 3rd party suppliers. Then OOPS I was installing new drivers for my GPU and things went bad. I restarted and got a grey X or stop sign half way through the process. Nothing I tried fixed the issue so before going to bed I let system X recover down-load and rebuild the system. It's running now but when I tried to reset TRIM I got this link that answered all my questions. http://www.cindori.org/trim-enabler-and-yosemite/
Bottom line don't buy stuff that apple doesn't sell or support if you want the latest system. The custom Mac Pro is not the future.
By the way if I had read the note from TRIM ENABLER instead of ignoring it it would have saved me 4 hours of trying to fix the issue.
Regards,
Bob
Reading that page is crucial for Yosemite users. I'm going to add a timer so the warning can't be skipped easily.
Yes. Unfortunately none of the copycat tools like Chameleon choose to disclose the potential consequences of this to the user. Maybe in order to give the appearance of being technologically superior (trust me, it's not). All I know is that I'm already dealing with having to give support to Chameleon users who turn to my website once they realize that the steps on Chameleon's support page for restoring their bricked machines are actually incorrect.
There's a lot of things wrong with Chameleon, and I might come off as trying defame a "competitor" for saying so (even though Trim Enabler is free). But there's simply a ton of bad software practises in this app that are affecting users negatively.
For instance, did you know that the developer is mining your hardware and sending information about your computer to his server? Without your permission? This includes your computer's serial number, OS X version, Mac model with hardware specs and more. If you don't believe me, just download a packet sniffer and see for yourself.
Please don't, I'm pretty sure almost all users of TE are reading and understanding perfectly. Fort those who don't, the addition of a timer likely won't persuade them to read or understand. For the rest of us, it will just be annoying.
Thanks for a great product.
I really didn't, when I installed TE on my Yosemite mini. And I wish I hadn't. Because I had to go back and re-install Yosemite when it started acting funny.
Yes, put a timer, or more explicit warning that includes the potential for system instability.
How do you safely use trim enabler?
Or I should say TRIM or not to trim? Now that I know what the big grey stop sign is and their is a possible terminal fix to repair. What is the safest way to use TRIM ENABLER?
Bob.
Or I should say TRIM or not to trim? Now that I know what the big grey stop sign is and their is a possible terminal fix to repair. What is the safest way to use TRIM ENABLER?
Bob.