yashsingh1/xdaforums huggingface dataset:
[Epic 4G General] sauron0101:
I'm guessing that we'll be fine for the duration of the phones after doing a bit more research on this one. It's true that all flash-based storage eventually loses its ability to store, but I don't think that we will see any ill effects, as was pointed above, for the duration that we own our phones. I'm leaning in favour of keeping CWM 3.
[Epic 4G General] ptfdmedic:
I think noobs point its that the risk is there. Whether or not it will ever happen is another story. He is warning of the potential problems. I prefer to know the risks before I make a decision to do something like this. I'm glad noob pointed out the risks and I also glad dameon took steps to help prevent this from happening. Hopefully the NAND will outlast the slider mechanism on my EPIC.
[Epic 4G General] fetalp:
I am curious are you (the DEVS) going to revert back then?
[Epic 4G General] Unknown Zone:
That is what I say, I had read about this issue of EXT4 a while back but from reading the article I was thinking I would be on another phone by then, Medic you are correct, heck I been paying TEP for 13yrs and only used it once so if the phone dies before one yr or two which I don't think it will happen I will just take it in and get a replacement that is what insurance is all about :)
[Epic 4G General] suzook:
Why does everyone always crap on noobnl? No wonder he left this forum. Im stayin on the regular FS. a question to noob....Will cw switch back to the orig fs?
[Epic 4G General] ptfdmedic:
Dameon created the kernel with support for both formats. There are roms that will run on both EXT4 and RFS. This is a great thing he did because it gives you the choice of RFS or EXT4 for the same exact rom. If you want to take the "risk" you can or if you want to play it "safe" you can do that also.
[Epic 4G General] kgbcapthowdy:
right but are YOU personally going to go back or stay with ext4?
[Epic 4G General] Dameon87:
Months my ass noob. It won't kill our nand any faster than rfs will.

Just because you didn't think of the idea or get the credit for it, doesn't make it bad.

I personally will be staying on ext4. I wouldn't do so if I didn't think it was safe. I do not have insurance to fall back on either.
[Epic 4G General] ptfdmedic:
While I really do appreciate noobs concern, I will stay with EXT4 at this point. I am very comfortable calling Sprint for a warranty exchange over the phone

IF

it were to come down to that. I'm not worried to much at this point..Memory can go bad at any time. That's the nature of technology. I mean really it's only a phone. It's not like it would be the end of the world....
[Epic 4G General] fetalp:
Well, between the two Devs both have contributed a lot to the EPIC forums. Noobnl help get things started and going, but now I see Dameon stepping up and taking things further. I appreciate both sides of this debate, but Dameon did make it possible for us to use both RFS and EXT4. It's up to the Devs if they choose to add " using EXT4 MAY have risks" ;)

In the END just rooting is a RISK. I have done the ROOT why not do the others:D
[Epic 4G General] formula84:
From noobs first post from what I gather is he is pointing out that on nexus google decided to put YAFFS2 on the oneNAND rather than EXT4, but what I don't get is the point its not clear, we don't have an option for YAFFS2 only RFS or EXT4. As pointed out by others prior some say that EXT4 can lead to less writes.

Only thing that would make sense from an argument standpoint would be to put out some number facts of RFS vs EXT4 and try to explain with numbers how he came to this "months" conclusion.

EXT4 has big performance gain, I have insurance and will use it if need be bottom line.
[Epic 4G General] lviv73:
Yea ima stay with Ext4 because I got waranty but would revert back if I dint.Does disabling Ext4 Jornaling minimizes nand wear out?
[Epic 4G General] JungleJiujitsu:
Thanks for posting Noobnl! I definitely now see the clear difference in risk b/w leaving RFS and migrating to EXT4! Yes, we have insurance and whatnot but is it really worth the headache of having to go through all that? At least to me its not. Being w/o my phone for just a few hrs is enough time, like when I head off to work and leave it behind at home, but I especially don't want to even think about having to go through days if it comes down to getting it replaced due to damages.
[Epic 4G General] danweb66:
I would also like to know if we disable the journaling like mammons mod does, would that reduce the wear. Also I would like to see some numbers if at all possible to compare the two. In all as far as what google sprint and samsung decide to go with i dont care that much because look they wont officialy release froyo for our phones because they say its not stable enough but we've been using it for over a month now and i have not had one problem with it. I am not doubting anything anyone is saying here i would just like to see some numbers before I ditch somthing that makes my phone work way better than it did before.
[Epic 4G General] noobnl:
... wow I was just pointing a problem with ext4 and you accusese me of not getting the credit of not thinking about the idea.. I thought about ext4 buti didn't want to risk people phones by potently bricking by going to ext4
[Epic 4G General] ericizzy1:
hi noob and daemon, PLEASE try not togo personal, we love both of your work, and would love to see it taking all of us forward with your great work.

we understand both of your view on this, let us make our own decision on this, no need to fight over this.

thank you both.
[Epic 4G General] lviv73:
Is it possible for ya to make YAFFS2 for our Epic?Im sure its better than RFS and same wear out I take?
[Epic 4G General] Migital Warfare:
What I don't get is everyone saying they'll use the sprint insurance if they mess up their phone by doing this. By doing this, if Noob is correct, you won't be able to flash back to the stock ROM, and therefore, would be out of warranty. If you're out of warranty, Sprint won't cover your device, so how does everyone expect to be able to use their insurance if it's quite clearly their own fault for ruining their phone?
[Epic 4G General] danweb66:
even then i could just say my phone was lost and pay the deductable but if you were not able to go back to stock I would imagine you could still flash stock and your phone would not work and they would not know why they would just see that it was not getting past the boot screen.
[Epic 4G General] :
So where does the performance increase for ext4 come from? It looks like the nexus s has a /system partition that is actually on an ext4 filesystem on the internal SDCard. Is it possible for us to arrange the epic similarly? That is, can we leave the modem, cache, ramdisk and kernel on a yaffs2 system on the oneNand, and then port the /system directory to an SDCard with an ext4 filesystem and potentially see the same performance increase without the limitations of OneNAND?
[Epic 4G General] kenvan19:
My understanding is that if the worst happens in this case that your phones memory will be completely corrupted and therefore not bootable. Meaning there is really no proof of rooting/modding but also no settings or apps stored so pretty much everything would be a total loss. Could be wrong, just giving you my reading of this.
[Epic 4G General] awrnsmn:
Because people like to ABUSE the system. That's not what warranty is for. It's for MANUFACTURE defects and ACCIDENTAL BREAKS, not when you know there are potential risks, and do it anyway. Since Samsung is NOT using ext4 then you are at fault. I will not argue about this nor defend my position, but you KNOW yourselves that using warrany like this is wrong (that's why people flash to stock before returning their phone). Noobl, thanks for the heads up as I will not use it because the risk is higher than I would like to take on my expensive handset! As for other devs in here, still thank you for all your hard work for our Epics! (including Noobl)
[Epic 4G General] sauron0101:
Okay, this is starting to turn into a flame war. I think that everyone needs to take a deep breath, calm down, and relax. Nobody call each other names or accuse each other of abusing anything.
[Epic 4G General] Dulanic:
Seriously... why is everyone jumping down throats here? Both noobnl and daemon have done a lot of work for us. We appreciate both sides of this, but no reason to take it personal. Obviously both of you know more than 99.99% of the users on these forums, and it is good to hear both sides of it. We can then make a educated decision on which way we want to go.
[Epic 4G General] ptfdmedic:
By your logic then you shouldn't be on a custom ROM then. Because rooting voids your warranty as well. I'm just saying. But that said I wasn't suggesting ABUSE anything. If your phone fails it fails. There would be no way to know for sure what caused it. You just call 611 and tell them that it won't boot. They send you out a replacement. But I think we are getting off topic. I do respect your ethics though. :)
[Epic 4G General] sinman02:
Danger is my middle name....(raises one eyebrow...) I think I'll stay with ext4... Performance is paramount to me...if I could strap on a turbocharger I would...LOL
[Epic 4G General] JungleJiujitsu:
From what is being posted only one person is taking it personal and accusing the other of things that are not even true! And that person being accused is merely defending himself and his opinion so really, this should be worded differently and directed towards that one person taking it to a whole different level only because he does not like what is being stated! I agree, it should definitely not be at this level and toned down a notch.
[Epic 4G General] Dameon87:
As I said. I would not have done the work and recommend ext4 if I did not do the research first.

Our wear leveling attempts to equalize the rate at which wear of the nandchip occurs by writing to different blocks.

This argument is moot because there is absolutely NO proof that ext4 causes more write operations than rfs. As ext4 uses delayed journal writes, it may infact write less than rfs. There is a nice post ill reference when I get home.

That is why I'm jumping on noob, because he has absolutely no proof or evidence to support HIS accusation that it kills our nand chip.
[Epic 4G General] volDeus:
I'll beta test...
[Epic 4G General] daryelv:
Just wait until we get the kernel source from Samsung... then you'll start seeing new governors, overclocking, undervolting, BFS, CFS, and all sorts of new goodies.

-Daryel
[Epic 4G General] nadcicle:
I love you guys.

No, really I do. Please stop the violence and increase the peace :D

Chill out.. listen to some 3 little birds and take a nap and reevaluate each others views please.

... Don't worry... bout a ting.... cause every little ting... is gonna be alright!!
[Epic 4G General] rafal2006:
you right i think noob should have proof before statement like this its probably cause panic attack for couple thousand people .

btw they sad masturbation leads to blindness
[Epic 4G General] dhvmoon:
I found a lot of answers to the issues / questions brought up on this topic have already been covered in this very informational thread: [Q] OneNAND Wear Leveling

Specifically, in regards to wear leveling and oneNAND, the conclusion was "wear leveling is handled 100% correctly regardless of filesystem, as long as one of the STL (Sector Translation Layer) block devices is used."

That would lead me to the question, is a STL block device in use when using the ext4 filesystem?
[Epic 4G General] squshy 7:
Yeh I have to slightly agree with dameon. There is evidence that supports him.

That being said...I'm also a huge fan of conjecture. And I think that's what noob was doing. Even tho its lacking anything concrete, it makes sense in a pure logical way. We do only have 512mb to work with, so the traditional methods of dealing with bad blocks could be potentially detrimental. If I had to take a guess, noob, when you thought of using ext4 in the past, you surmised that information with what you already knew about the situation.(like coming to a conclusion about somebody after spending a short time with them; you could be right, you could be wrong) (FYI, all of what I'm writing right now is conjecture lol) But I can totally agree with that.

So for everybody wondering what to do with themselves (like myself), rushing into devving a reformat to ext4 definitely could have had disastrous side affects. But I'm very confident in believing that dameon took the necessary steps with his devving to ensure those consequences did not manifest themselves. I believe he did his homework, does NOT want to tarnish his name, and made 100% sure that the product he has put out will not harm our phones. (Aside from us all being noobs and bricking our phones, of which he has no control over our noobiness lol)

Sent from my baked and emotionless SPH-D700
[Epic 4G General] smoothone:
What a lightweight, what are you a cop, DEA, Fed? Cellphone companies have been sticking it to us for YEARS! If I get a chance or the need to I will gladly stick it right back to them and not lose an ounce of sleep!
[Epic 4G General] Randy_T:
FWIW, I support this direction. (and I am not paying for insurance either)

SSD/EXT4 is working well on many other Linux platforms. With proper tuning, it should cause fewer writes than RFS.

Any chance we can add some additional tuning parameters to the mount options?

Specifically would like to see: nobh, barrier=0, data=writeback

I've tried fiddling this through init.d scripts but cannot seem to make it happen. Any pointers to where these are set would be appreciated. Would like to start helping out with these types of improvements.
[Epic 4G General] jbadboy2007:
READ THE LINK.... the nand chip is not responsible for wear leveling as long as dameon left the stl intact and working properly. So Dameon did you leave stl in?
[Epic 4G General] rygran87:
Insurance doesn't have the same limitations as a warranty. I've told insurance that I threw my motoQ9c against a brick wall and they gave me a new phone right away. That was clearly my own fault.
[Epic 4G General] buggerritt:
This is pure lameness.
[Epic 4G General] awrnsmn:
Yep, i'm on a custom rom (Viper!!), but at my own risk.....thank you for the kind comment on the ethics and for the gentle response. :)
[Epic 4G General] daryelv:
This seems to be a very hotly contested argument not just in this forum/thread but all over the internet when discussing on other devices such as the Samsung tablet or even HTC devices.

What I personally came across from reading all the articles is that both Dameon and noobnl have their points and each is correct.

RFS does have wear-leveling and EXT4 does not.

EXT4 is much faster than RFS.

I saw several quotes around the 100K writes before failure. (To me, this only means that it will fail at some time, some people may get 250K before failure, some may get 50K).

For a flash-aholic, will RFS wear-leveling even matter since you're re-formatting /system, /cache, /data, etc. every week (or more often)? Do writes begin back at byte 0 or does the RFS wear-leveling move the write after a fresh format to byte XXX to "level" things?

-Daryel
[Epic 4G General] awrnsmn:
Warranty = free replacement insurance = $100 deductable (no matter what you do to the phone, for the most part)
[Epic 4G General] volDeus:
Then we can really burn our Epics up! I just thought the comment was a bit hilarious and wanted to give my vote of confidence in the same manner. Imagine making calls with a turbo duct-taped to the back of your phone... :D

It certainly will be lovely though, I am still a little torn between running 2.2 vs 2.1, considering the availibility of overclock kernels..
[Epic 4G General] rygran87:
Exactly. If I do something stupid to something I am not insuring and get a warranty replacement then THAT would be abusing the system. BUT I do insure all of my expensive toys just in case I do something stupid that destroys said toys.
[Epic 4G General] jbadboy2007:
DID you fn read the link posted here earlier the file system does not do the wear leveling so you already dont know what you are talking about....... Not only that dameon said there is wear leveling in the ext 4......
[Epic 4G General] awrnsmn:
No,(well, I am an officer for a local govmt agency, does that really matter though? Programming is my hobby) i'm a 40 something year old man who trys to set good moral foundations for my kids. So by your reasoning, Kolhs makes a healthy profit off their Dockers I buy, so maybe I should go in and switch tags between the dockers and wranglers.....stick it back to them huh? Don't like Sprints pricing.....go to Walmarts prepaid or something cheaper.....it's call capitalism.....doesn't mean we should screw them every chance we get.
[Epic 4G General] riceknight:
I really appreciate both Devs working to do what they think is right.

However I think this issue should have been brought up via PMs/chat/IRC between Noob and Dameon before it was just posted since it affects so many people.

A friendly heads up and discussion between two Devs could have saved a lot of headache. Thats what community is for right?
[Epic 4G General] LordLugard:
No effing way. My eyeballs would have fallen outta their sockets by now... :p
[Epic 4G General] awrnsmn:
Then I appologize....I thought we were talking about taking it to Sprint for warranty, for a free replacement.........my misunderstanding.....i'm done now.
[Epic 4G General] Mugen678:
Agreed. You can start with the premium data package charge if you want to define "sticking it to us". I never feel a bit of guilt when going in for insurance or what have you, I pay for it so why not have it pay for itself? I picked up 2 epics for $125 each from Best Buy, had Sprint roll my eligibility up 10 months on the secondary, and credit my account $150. Do you think that hurts my feelings? Nope, I consider that reimbursement for the countless hours I've spent dealing with the non-English speaking, muffled, in a loud environment, non-AMERICAN foreigners that do not know what they're doing. anyways...

This is good for anyone that may have questioned going to ext4. I say good work to both noob and dameon, There's always 2 sides in any equation. I myself have not gone to ext4 as of yet, only because of the updates in the rom I'm on haven't changed enough to justify the time it takes to get everything back to normal. But rest assured, I WILL go ext4.
[Epic 4G General] jbadboy2007:
Figures a guy like you would say that. you are what is wrong with this whole country. thinking that just because they are bigger that they deserve to bleed us dry and take everything they can get. and yeah we should stick it to them because they stick it to us more than we can. Capitalism needs boundaries not loop holes.
[Epic 4G General] Dameon87:
STL partitions are still indeed used. Therefore, wear-leveling is indeed working. /dev/block/stl9 10, and 11 are all STL partitions (Sector Transition Layers).
[Epic 4G General] jbadboy2007:
I totally agree thats why i almost think noobnl did this on purpose. WITH ALL LOVE NOOBNL BUT i believe you do act with alterior motives on this subject and the way you presented it. you have a great understanding of this phone and with your lack of evidence it just seems like you are attacking dameon.
[Epic 4G General] Randy_T:
Just to add a few more facts to this discussion, some good information here on how to enable wear leveling in EXT4 and how to test to see if it works.

https://sites.google.com/site/lightrush/random-1/howtoconfigureext4toenabletrimforssdsonubuntu
[Epic 4G General] jbadboy2007:
WELL awesome then devs please make us roms, mods and themes using the edify scripts. Thanks to everyones contribution to this phone. Dameon thanks for this awesome accomplishment and further development with this phone.
[Epic 4G General] daryelv:
Since when is "because he said so" a credible source? A credible source would be Samsungs source code. I've been in the mobile phone modding game long enough to regard these posts more with a YMMV attitude than take them as fact.

Here's an excerpt from a blog discussing whether or not wear-leveling is on the OneNand chip itself or within the RFS code.

So, it seems that it's possible that using EXT4 will be fine if the wear-leveling is on the OneNand chip itself. Continuing with this...

It shows that wear-leveling is actually a module that potentially is in the kernel.

This is all up to the user to decide still. Each user should make their own choices using the information presented.

I asked the question in my previous post about whether wear-leveling even mattered for a person that flashes a new rom every week. What did you contribute with your post?

-Daryel
[Epic 4G General] MeetFace:
You have to have boundaries in order to have loop-holes...silly man

...awww you delete your rant X^D
[Epic 4G General] adamw1101:
so if rfs also rewrites to nand doesnt that also mean that eventually rfs would kill the nand chip in due time? i know im a layman and am not versed in this area but the very nature of flash memory is that it has a finite lifespan as to how many times your can write to it (im assuming the chip uses SSD. for the time being i will stay with EXT4 until we reach a further conclusion my one question is if the chip we actually failing would there be tell tail signs before a complete fail. and would we have time to flash back to stock before a totally failure )(im not saying that it is imminent just a speculation and for my personnal info)
[Epic 4G General] danweb66:
• Power dissipation (typical values)

- Standby current : 10uA@1.8V, 20uA@2.65V/3.3V for single, 20uA@1.8V, 40uA@2.65V/3.3V for DDP

- Synchronous Burst Read current(54MHz) : 12mA@1.8V device, 20mA@2.65V/3.3V device

- Load current : 20mA@1.8V device, 25mA@2.65V/3.3V device

- Program current: 20mA@1.8V device, 25mA@2.65V/3.3V device

- Erase current: 15mA@1.8V device, 20mA@2.65V/3.3V device

• Reliable CMOS Floating-Gate Technology

- Endurance : 100K Program/Erase Cycles

- Data Retention : 10 Years

ok after researching, if you look at this bottom line even if you cut this in half using ext4 you will not be using this phone in 5-10 years not even 2.5. Also after researching there is realy no real life proof that ext4 will decrease the life span of this chip it is all theoretical. www.datasheetcatalog.org/datasheets2/12/1248447_1.pdf is where I got these specs.
[Epic 4G General] kenvan19:
Nevermind, I'm stupid and found my question had already been answered. Sorry.
[Epic 4G General] noobnl:
That means it will hold data for 10 years
[Epic 4G General] sinman02:
It has to be black duct tape...I can't be seen walking around town lookin' like a fool..:-)
[Epic 4G General] rygran87:
That's 9 years longer than I'll have the phone most likely lol. But seriously is that accurate? That's a lot longer than I'd ever expected. Something must be off.
[Epic 4G General] adamw1101:
Any chance we can get an android website to try to burn out a nand chip? I don't think we will truely know until we try to burn out a nand chip
[Epic 4G General] dcowboys2184:
so does that explain my situation with my phone only booting into download mode ... and not even turning on
[Epic 4G General] kenvan19:
+1 to this. Good idea!
[Epic 4G General] rygran87:
Ohhhh. Noob, were you saying that it wasn't the right calculation? So what's the right one?
[Epic 4G General] squshy 7:
I'm almost 100% sure the data retention time is irrelevant. I think it simply refers to how long the data will still be readable if you say, left it alone for 10 years. I think that's a timetable w/o write/erases

Sent from my baked and emotionless SPH-D700