Disabling TRIM in El Capitan

[dyn]

Nope, was just curious since you brought up the backup part I actually don't backup a lot of data due to it being replaceable. VM's for example. They are either documented or on a different machine so only crucial data has to be backed up. I currently have 1 machine for testing El Capitan and I've enabled TRIM on that one for testing purposes (my job is my hobby too ).

The only FUD about TRIM is that it is a necessity, that you need it for an SSD to work properly. It isn't and it never has been. It's about the exact opposite: people being afraid/very concerned their SSD might not work properly without TRIM. The only good advice you can give someone when switching to an SSD is to not worry about it. Use it like it is an HDD and don't apply all sorts of "tweaks".

 

[crjackson2134]

The only FUD about TRIM is that it is a necessity, that you need it for an SSD to work properly. It isn't and it never has been.

There's plenty of other FUD out there besides necessity. I didn't say anywhere that it's a requirement, it's not.

The only good advice you can give someone when switching to an SSD is to not worry about it. Use it like it is an HDD and don't apply all sorts of "tweaks".

That's exactly what I did when installing the Apple/Samsung SSD. OS X turned on Trim of it's own volition, there was no tweaking involved for that drive. That said, I turned trim on for my 840 Pro and it works as intended under all the conditions I subjected it to, including as a boot drive.

Trim is a good thing even if not REQUIRED for operation. That's not to say (as already stated) that it's appropriate for every possible use case.

 

[dyn]

If you really think TRIM isn't a necessity you wouldn't say that it is a good thing to enable even if it isn't required. By saying that you are simply saying it is a necessity and appropriate for every possible use case. That's simply FUD because in reality it really doesn't matter if you use TRIM or not. If you really think that TRIM doesn't matter you'd say so (or "don't worry about not having TRIM, it'll work"). The only reason to enable TRIM is for troubleshooting when you have performance issues. In some cases it fixes these, in most it won't so it's a bit of a long shot.

 

[crjackson2134]

If you really think TRIM isn't a necessity you wouldn't say that it is a good thing to enable even if it isn't required. By saying that you are simply saying it is a necessity and appropriate for every possible use case. That's simply FUD because in reality it really doesn't matter if you use TRIM or not. If you really think that TRIM doesn't matter you'd say so (or "don't worry about not having TRIM, it'll work"). The only reason to enable TRIM is for troubleshooting when you have performance issues. In some cases it fixes these, in most it won't so it's a bit of a long shot.

Okay, now you have lost your way. Now you are telling me what I think and why I think it. I've lost respect for you due to your inability to state your opinion without resorting to such tactics. Just because you hold a certain opinion or belief gives you no right to declair you know my motives or thoughts.

Have it your way... You have moved away from rational, so I'm out...

 

[flowrider]

And how about the most common failure: a soft fail after a few weeks/months? How do you manage that (and make sure your backup doesn't contain corrupted data)?

I have been using Macintoshes since 1986, and believe it or not, I have never lost a byte of critical data. Have I lost HDDs? Of course I have. But my backups always came through. Have I ever lost an SSD? Nope, But when and if it happens, I'm ready. In the meantime, I'm happily still running Trim without a care in the world.

Lou

 

[/V\acpower]

Well, the thing about TRIM is that the failure mode is subtle: you could be perfectly happy for months until you try to open a photo one day and the file turns out to be full of zeroes instead of your precious data.

There's so much superstition about how TRIM works (and so much anger that I'll probably regret wading in), but it's very simple: the TRIM command is a way for the operating system to tell an SSD that it no longer cares about a block of data.

Discarding data is obviously an inherently dangerous thing for a storage device to do, which is why TRIM is disabled by default on third-party SSDs and why you should do some research before you enable it.

What could possibly go wrong? Well, the OS or SSD firmware could be buggy and discard the wrong block. There could be subtle interactions; an SSD could have a TRIM bug that only manifests after a certain sequence of commands which happens to be more common on a certain OS (or OS version). Either way, silent data loss that you may not notice for months or years. Yay!

TL;DR: TRIM is not magic. You should know what you're doing before you enable it.

(Me? I enabled it on my Crucial C300 seconds after learning about trimforce, of course ).

Yeah, the SSD could be buggy and discard data with the TRIM command.

However, that argument could be used for about anything relating to storage. Your OS could be buggy and delete data on a regular HDD, a HDD could stop working at any given time. Your firmware could always be buggy for whatever reason not related to TRIM at all.

That's why you need a backup drive for everything, because no storage is completely safe.

 

[/V\acpower]

Nope, was just curious since you brought up the backup part I actually don't backup a lot of data due to it being replaceable. VM's for example. They are either documented or on a different machine so only crucial data has to be backed up. I currently have 1 machine for testing El Capitan and I've enabled TRIM on that one for testing purposes (my job is my hobby too ).

The only FUD about TRIM is that it is a necessity, that you need it for an SSD to work properly. It isn't and it never has been. It's about the exact opposite: people being afraid/very concerned their SSD might not work properly without TRIM. The only good advice you can give someone when switching to an SSD is to not worry about it. Use it like it is an HDD and don't apply all sorts of "tweaks".

It depend of your definition of "a necessity".

Trim isn't a necessity for your SSD to work as a storage device. (read/write data)

However, Trim is a necessity if you want to have your SSD to keep the write speed it had in the beginning for all it's usable life (especially if you want to use most of it, and not just like a third of the storage space).

Without TRIM, especially if you want to use most of your storage space on your SSD, you need TRIM to keep performance. That's a "necessity" in that sense.

But yeah, it will still work without TRIM.

 

[flowrider]

And with HDDs there were programs that would "optimize" the data by moving it around so that the drive would be quicker. It was clunky and required the user to set aside a block of time to perform this maintenance. The real beauty of Trim is that it does this and more on an SSD in real time.

Lou

 

[SG-]

the Samsung/Linux TRIM issue is related only to Linux and Samsung has provided a linux kernel patch to fix it.

https://blog.algolia.com/when-solid-state-drives-are-not-that-solid/

"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."

 

[g-7]

Is TRIM necessary? Well, take a look here: #99

Is TRIM safe? I have been using it for nearly 5 years and yet to see any data corruption. I'm using Samsung drives only (no Sandforce controller).

That's my experience only. Maybe I'm just plain lucky. Doesn't seem to work with lottery tickets, though

 

[dyn]

It depend of your definition of "a necessity".

Trim isn't a necessity for your SSD to work as a storage device. (read/write data)

However, Trim is a necessity if you want to have your SSD to keep the write speed it had in the beginning for all it's usable life (especially if you want to use most of it, and not just like a third of the storage space).

That's the FUD we discussed earlier. Any SSD since 2008 by default comes with a mechanism to keep write speeds at the same level as when the SSD left the factory. It's called Garbage Collection (GC). In late 2009/2010 TRIM was introduced as a command in the ATA spec to make things a bit more efficient. TRIM has never been a necessity, it's nothing but a nice addition to make things more efficient. That and only that was and still is its intended purpose. In order to keep the write speeds up you indeed need something that clears out unused cells, they knew that from the start (they ran into that and fixed it with GC).

Another problem is that you can't keep writing speeds at the same level as when you got your SSD if you use it. The problem is that any SSD (and even HDD) will slowdown when you fill it with data. GC and TRIM will only come into play when you actually delete data. If you don't then GC nor TRIM will work and you won't get any speed back.

Something people also tend to forget is the fact that TRIM doesn't work when you use RAID. It also doesn't work with SAS because it's only in the ATA spec. SAS does have an equivalent that was already used back in the SCSI days.

I know this is a really difficult concept to grasp for 90% of the users out there. TRIM doesn't do what you think it does and it is not a necessity because any SSD already comes with a mechanism to fix the write speed issue. That's why you needn't worry if your SSD doesn't do TRIM.

Is TRIM necessary? Well, take a look here: #99

Samsung 840 EVO here which I've had for a couple of years now, Samsung 830 same thing and some old OCZ Vertexes (the very first one, aka the proper ones) I've had for almost 7 years now. I've ran these kind of benches over the course of years and I'm not seeing huge drop offs. None of them have ever ran with TRIM. So is TRIM necessary? No it's not.

What is necessary is to have a good understanding of what GC and TRIM are and how they work. In case of GC you need to let the disk idle for a little while. If the disk never does that or is unable to do that quite often then TRIM is more efficient because of how it works. Whenever you delete something the TRIM command will be sent to the disk and the disk will act on that. Again, TRIM isn't necessary, it's just more efficient in certain cases like this one. This is a good example of when you run into problems and where you definitely should try to see if TRIM solves the problem.

You want to take a look at SSDs used in servers and workstations configured in RAID arrays. They can't do TRIM because it isn't supported in combination with RAID. Yet none of those machines have problems.

Is TRIM safe? I have been using it for nearly 5 years and yet to see any data corruption. I'm using Samsung drives only (no Sandforce controller).

TRIM requires support in the OS, in the driver and in the SSD. The TRIM implementation in OS X is different from Windows/Linux/FreeBSD/etc., the one in Windows is different from OS X/Linux/FreeBSD/etc. and so on. In the past you had to install a specific Intel driver if you wanted to have TRIM support for your Intel SSD. TRIM can be safe as we've seen with Windows but it can also be troublesome as we've seen in the past with both Windows, Linux and OS X (driver issue, controller issue, firmware issue). I have no idea how well the TRIM support in OS X is. It's fine for Apple's own drives but they can control them almost entirely (they can match OS, driver and firmware of the controller which they can't with 3rd party disks).

That's my experience only. Maybe I'm just plain lucky. Doesn't seem to work with lottery tickets, though

My feeling is that we're ok with the TRIM support but reality is that we simply don't know a lot about it yet. It simply is too soon to tell. That's why we need to be a bit careful and not let ordinary users use it (we've seen what happens when they install public beta's...).

I find it rather funny that many hold of installing OS X updates yet immediately turn on TRIM support the moment it's in OS X. What happened to playing safe?

 

[h9826790]

TRIM is not necessary, but SSD will work better with that.

GC is not necessary, but SSD will work better with that.

SSD is not necessary, but computer will work better with that.

Computer is not necessary, but human will live better with that.

Human is not necessary, but the Earth will live better without us .

 

[crjackson2134]

TRIM is not necessary, but SSD will work better with that.

GC is not necessary, but SSD will work better with that.

SSD is not necessary, but computer will work better with that.

Computer is not necessary, but human will live better with that.

Human is not necessary, but the Earth will live better without us .

E-I-E-I-O

 

[/V\acpower]

That's the FUD we discussed earlier. Any SSD since 2008 by default comes with a mechanism to keep write speeds at the same level as when the SSD left the factory. It's called Garbage Collection (GC). In late 2009/2010 TRIM was introduced as a command in the ATA spec to make things a bit more efficient. TRIM has never been a necessity, it's nothing but a nice addition to make things more efficient. That and only that was and still is its intended purpose. In order to keep the write speeds up you indeed need something that clears out unused cells, they knew that from the start (they ran into that and fixed it with GC).

Another problem is that you can't keep writing speeds at the same level as when you got your SSD if you use it. The problem is that any SSD (and even HDD) will slowdown when you fill it with data. GC and TRIM will only come into play when you actually delete data. If you don't then GC nor TRIM will work and you won't get any speed back.

Something people also tend to forget is the fact that TRIM doesn't work when you use RAID. It also doesn't work with SAS because it's only in the ATA spec. SAS does have an equivalent that was already used back in the SCSI days.

I know this is a really difficult concept to grasp for 90% of the users out there. TRIM doesn't do what you think it does and it is not a necessity because any SSD already comes with a mechanism to fix the write speed issue. That's why you needn't worry if your SSD doesn't do TRIM.

What exactly do we think TRIM does ?

I mean, you say that we simply don't understand TRIM while at the same time you explain it exactly like we do.

Same thing with the Ars article in the first page, you say we don't understand the article while you are explaining the exact same thing we do.

Anyway, the fact is that TRIM help in maintaining performance (because writing to free space is faster that overwriting used space that the OS label to itself as usable space) and also help reducing wear (since the SSD can copy around big chunk of useless data is TRIM isn't enabled.) It's a net win.

After that, it's a matter of implementation...like every hardware/software feature, but that is why we have backups in OS X like Time Machine.

 

[Weaselboy]

Anyway, the fact is that TRIM help in maintaining performance (because writing to free space is faster that overwriting used space that the OS label to itself as usable space) and also help reducing wear (since the SSD can copy around big chunk of useless data is TRIM isn't enabled.) It's a net win.

I agree. I just don't see any logical argument that TRIM is not a good thing. It is worth noting that Apple enables TRIM on its flash storage Macs.

The only issue I see up for debate is if one thinks it is worth enabling TRIM on third party devices with the new Apple enabler tool given your specific SSD model may not have been tested by Apple. For me, that is just something users need to understand there may a slight risk and decide for themselves if the risk is acceptable. I don't see a clear right or wrong answer to this question either way. Just a personal choice.

That said, like you mentioned, if you have good backups, at this point the risk seems pretty low.

 

[crjackson2134]

I agree. I just don't see any logical argument that TRIM is not a good thing. It is worth noting that Apple enables TRIM on its flash storage Macs.

The only time it's not a good thing AFAIK, is if you happen to have some old, problematic SSD that the firmware was never able to correct. If you have something like that, the Trim would be a poor fit. However if you have something like that, the SSD itself (IMO) is the problem, not Trim. The SSD shortcomings are what needs to be addressed. If the SSD isn't up to the task, it's bye-bye SSD for me.

 

[2984839]

I agree. I just don't see any logical argument that TRIM is not a good thing. It is worth noting that Apple enables TRIM on its flash storage Macs.

The only issue I see up for debate is if one thinks it is worth enabling TRIM on third party devices with the new Apple enabler tool given your specific SSD model may not have been tested by Apple. For me, that is just something users need to understand there may a slight risk and decide for themselves if the risk is acceptable. I don't see a clear right or wrong answer to this question either way. Just a personal choice.

That said, like you mentioned, if you have good backups, at this point the risk seems pretty low.

Agreed, though another thing to be factored in is that Yosemite requires kext signing to be disabled in order to use Trim on 3rd party drives. The security tradeoff here is not at all worth the benefits of Trim IMO.

If it can be enabled without this, then go for it. But the way some people here treat Trim like a magical incantation that's absolutely essential and should be enabled at all costs is foolish. It's perfectly fine to use an SSD without it. None of my SSDs have ever had Trim enabled and they are all 3-5 years old and are not noticeably slower.

 

[crjackson2134]

Agreed, though another thing to be factored in is that Yosemite requires kext signing to be disabled in order to use Trim on 3rd party drives. The security tradeoff here is not at all worth the benefits of Trim IMO.

If it can be enabled without this, then go for it. But the way some people here treat Trim like a magical incantation that's absolutely essential and should be enabled at all costs is foolish. It's perfectly fine to use an SSD without it. None of my SSDs have ever had Trim enabled and they are all 3-5 years old and are not noticeably slower.

No, 10.10.4 does not require kext signing to be disabled.

 

[Weaselboy]

Agreed, though another thing to be factored in is that Yosemite requires kext signing to be disabled in order to use Trim on 3rd party drives. The security tradeoff here is not at all worth the benefits of Trim IMO.

If it can be enabled without this, then go for it. But the way some people here treat Trim like a magical incantation that's absolutely essential and should be enabled at all costs is foolish. It's perfectly fine to use an SSD without it. None of my SSDs have ever had Trim enabled and they are all 3-5 years old and are not noticeably slower.

Like CR mentioned, with 10.10.4 and now El Capitan, you no longer need to disable kext signing.

It is great that you have had a good experience without TRIM, but not everyone does. Some see very noticeable drops in write speeds over time. There was a comment linked up in post #35 showing one example and there are many many more here in the forums.

 

[2984839]

Like CR mentioned, with 10.10.4 and now El Capitan, you no longer need to disable kext signing.

It is great that you have had a good experience without TRIM, but not everyone does. Some see very noticeable drops in write speeds over time. There was a comment linked up in post #35 showing one example and there are many many more here in the forums.

Thanks, I did not know that about 10.10.4.

The key to running a SSD successfully without Trim is to leave a lot of spare room. I only give the OS 96 GB out of a 120 or 128 GB drive. If the drive supports garbage collection, this combined with the built in over-provisioning is more than enough to keep speeds high. It's actually a lot more than necessary, but I don't need the space so it's not a problem for me.

 

[lssmit02]

the Samsung/Linux TRIM issue is related only to Linux and Samsung has provided a linux kernel patch to fix it.

https://blog.algolia.com/when-solid-state-drives-are-not-that-solid/

"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."

Exactly. I have not seen a link to any reports that TRIM with third party SSDs on OS X has caused a problem. Only "reference" is Apple's CYA note.

EDIT: There were reports of early Sandforce-based SSDs having problems with Trim, such as OWC drives. However, now even OWC is saying that the TRIM command is compatible with all their drives have have the latest firmware.

However, our testing has shown no issues with using Trimforce or third-party enablers with an OWC SSD.

 

[Weaselboy]

The key to running a SSD successfully without Trim is to leave a lot of spare room. I only give the OS 96 GB out of a 120 or 128 GB drive. If the drive supports garbage collection, this combined with the built in over-provisioning is more than enough to keep speeds high. It's actually a lot more than necessary, but I don't need the space so it's not a problem for me.

If you look over forum posts here, that is not always the case. There are many many reports here of write speed slow downs that are fixed by a quick TRIM run, even on drives with lots of free space.

 

[crjackson2134]

Much of it has to do with the type of use. If you are booting the OS and launcghing apps. and not much else, then you can get away with healthy overprovisioning sometimes. However, if you are using the SSD in such a way that many write cycles are occuring, you're likely to notice degradation of performance over time (without Trim).

 

[dyn]

What exactly do we think TRIM does ?

I mean, you say that we simply don't understand TRIM while at the same time you explain it exactly like we do.

No you don't because if you did you wouldn't disagree with me.

What most of you forget is:

1. TRIM doesn't increase performance nor does GC
2. only write speeds are an issue, not read speeds or anything else
3. the issue is caused by memory cells being filled with data
4. there is no solution
5. the workaround is to erase data from cells marked as unused
6. thus the more you fill your SSD with data the slower it becomes and nothing TRIM/GC will do about that
7. they knew about the issue from the very first beginning and already dealt with that by using Garbage Collection (GC)
8. GC goes through everything in a smart way (it uses an algorithm) and does this at idle time
9. TRIM is only an ATA command
10. TRIM was meant to do what GC does more efficiently by only deleting the contents of the memory cells used to store the data that just got deleted by the user
11. TRIM doesn't work in RAID configs thus enable it is useless
12. TRIM requires support from OS, driver and SSD
13. TRIM is highly dependent on how well it is implemented in OS, driver and SSD
14. GC only how well the manufacturer of the SSD implemented it
15. we've seen issues with TRIM wreaking havoc
16. SSDs do NOT work better with GC or TRIM, speed is better when using GC/TRIM
    
17. experiences over the years since 2008 as well as testing by some websites (Toms Hardware being one) has shown that overall both GC and TRIM do an equally good job
18. Some SSDs have performance issues which manufacturers fix by releasing new firmware versions thus not every performance problem is caused by GC/TRIM
    
19. since an SSD comes with a mechanism to cope with aforementioned problem TRIM is not a necessity nor requirement but only a nice to have as it does it more efficiently
20. thus TRIM is not the silver bullet most of you think it is
21. And lastly: when asked people evade the question or repeat basics but don't explain why TRIM is a necessity. Nobody has ever shown evidence that TRIM is a necessity and GC isn't.
22. This doesn't mean TRIM is bad, not a good thing and so on; it only means that one shouldn't exaggerate what it is.

The problem is that most of you think that TRIM is the only thing that will reduce the effects of aforementioned problem. It isn't and never has been. It is only the more efficient way for doing so and thus not a necessity. You can do without.

Anyway, the fact is that TRIM help in maintaining performance (because writing to free space is faster that overwriting used space that the OS label to itself as usable space) and also help reducing wear (since the SSD can copy around big chunk of useless data is TRIM isn't enabled.) It's a net win.

This is the most technical answer as you'll get from people. The entire point I'm making is in bullet points 16 and 18: the SSD is already helping maintaining the performance by itself and it is very capable of doing that. Unfortunately people forget about that.

After that, it's a matter of implementation...like every hardware/software feature, but that is why we have backups in OS X like Time Machine.

And why you should play around with it on a test machine I wouldn't recommend it yet for the general public as we don't know the exact workings yet. Once we start getting lists of SSDs that work and don't work we can go that route.

TL;DR: people are exaggerating what TRIM is.

I just don't see any logical argument that TRIM is not a good thing. It is worth noting that Apple enables TRIM on its flash storage Macs.

That would be because it never was a debate. The exaggeration of TRIM being THE solution is.

The only issue I see up for debate is if one thinks it is worth enabling TRIM on third party devices with the new Apple enabler tool given your specific SSD model may not have been tested by Apple. For me, that is just something users need to understand there may a slight risk and decide for themselves if the risk is acceptable.

It is just like with the public betas: people don't understand what that entails. The TRIM for 3rd party SSDs is the same thing. There can be risks which is why it isn't enabled by default, why you need to enable it via a command on the commandline and why, when enabling, it gives you a big warning. If you decide to ignore all that then fine but at least do so when you fully understand what it means (aka make sure you have proper backups and/or use it on a test machine to play around with and gain some experience).

It is great that you have had a good experience without TRIM, but not everyone does. Some see very noticeable drops in write speeds over time. There was a comment linked up in post #35 showing one example and there are many many more here in the forums.

Note the SSD brand, model and date posted. There is a known issue with this particular model and at the time of posting there wasn't a proper solution. A month later there was a new firmware version that fixed the issue for most users but there are still some that run into performance issues. It's not a very good example tbh.

Much of it has to do with the type of use.

Like I explained, things are different when you use it in RAID or as a scratch disk. The issue GC and TRIM try to reduce (not fix mind you!) is with deleted data. If you use the SSD to store data then it won't do anything. Results also greatly depend on how well the SSD does TRIM. There are some that do not cleanup everything, they leave stuff whereas the GC does a better job at that.

 

[Weaselboy]

That would be because it never was a debate. The exaggeration of TRIM being THE solution is.

I guess I'm just not seeing this exaggeration and misleading information you keep talking about. TRIM is a good thing and that seems to be what most in here are saying. So just decide if you think having TRIM on is worth using this new and perhaps risky utility.

IMO part of the problem here is you keep using the word "necessary" and that is about impossible to define, so the argument goes in circles.

Note the SSD brand, model and date posted. There is a known issue with this particular model and at the time of posting there wasn't a proper solution. A month later there was a new firmware version that fixed the issue for most users but there are still some that run into performance issues. It's not a very good example tbh.

You should reread the linked comment. The drive in the comment is a Samsung 840 Pro and not the EVO model that was impacted by a firmware bug that caused read speed slowdowns. There are many more examples of this same thing in the forums.