# HOWTO: Disable Jellybean Filesystem Check at Boot



## tiny4579 (Oct 21, 2011)

```
<br />
DISCLAIMER: Do not follow this process unless you are sure of what you're doing.  Disabling filesystem checks on /data and /cache can have negative impact on the phone but should allow it to boot even if the FS is corrupt; however there is no danger of making things work. I don't expect issues but follow at your own risk.  In short it should revert to the no check behavior from ICS.<br />
```
First of all, I've heard several times that the long boot times are due to Jellybean's standard functionality and there's nothing to be done to change this. I doubted that as I've not seen the long Google boot times on my Nexus 7. I decided to post this since I was tired of hearing nothing could be done.

When I saw a post from abqnm mentioning the fstab.tuna, I decided to investigate. I compared this to my Nexus 7 and saw one key difference. On the Nexus 7 there's no check option in the fstab.grouper but there is in the fstab.tuna.

Anyways, doing this change requires knowledge of unpacking a boot.img.

Steps:
1. Unpack boot.img
2. Edit fstab.tuna from the extracted ramdisk.
3. Modify the /data and /cache lines so check is not in the list
4. Save the file and repack the boot.img
5. Flash the resulting boot.img with fastboot.
6. Voila, no long boot times.

An example of what's changed.
Old:

```
<br />
<br />
/dev/block/platform/omap/omap_hsmmc.0/by-name/cache	 /cache			  ext4	  noatime,nosuid,nodev,nomblk_io_submit,errors=panic,noauto_da_alloc,barrier=0,data=writeback	wait,check<br />
/dev/block/platform/omap/omap_hsmmc.0/by-name/userdata  /data			   ext4	  noatime,nosuid,nodev,nomblk_io_submit,errors=panic,noauto_da_alloc,barrier=0	wait,check,encryptable=/dev/block/platform/omap/omap_hsmmc.0/by-name/metadata<br />
```
New:


```
<br />
/dev/block/platform/omap/omap_hsmmc.0/by-name/cache	 /cache			  ext4	  noatime,nosuid,nodev,nomblk_io_submit,errors=panic,noauto_da_alloc,barrier=0,data=writeback	wait<br />
/dev/block/platform/omap/omap_hsmmc.0/by-name/userdata  /data			   ext4	  noatime,nosuid,nodev,nomblk_io_submit,errors=panic,noauto_da_alloc,barrier=0	wait,encryptable=/dev/block/platform/omap/omap_hsmmc.0/by-name/metadata<br />
```
A few remarks. First, due to the possibility of the filesystems being corrupted with fsync off it's not recommended to do this combined with fsync off. Second remark is the disabling check should make the process similar to ICS so it shouldn't be dangerous. There just won't be any automatic filesystem checks. Third, grouper did not have this check option so I don't see why the Gnex does unless it was missed on the grouper or they forgot to remove it on the Gnex.


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## ITGuy11 (Jun 10, 2011)

A zip would be awesome!

Sent from my Galaxy Nexus using Tapatalk 2


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## yarly (Jun 22, 2011)

Sigh, others and myself have know about this for quite a while and this is a *very bad idea and why no one has given any sort of "guide."*

You want to corrupt your filesystem? Feel free to do the above, just don't come and complain about it on the forum after you do it. Disabling something that's running for a good reason, is just stupid. I know the OP gave warnings, but still, it's just a not a good idea and just giving my advice as part of the staff.

Worse that can happen? You have to reformat your data partition and cache, wiping out all your apps and saved data.

Thank you.


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## tiny4579 (Oct 21, 2011)

Not checking the filesystem doesn't corrupt it. Yarly, can you answer why the nex 7 doesn't have this check option on if having it missing is so bad? Also if it were that important official ports would have this check option in their fstab file. I'll take out the offer to make a script but still don't get the fear.

Sent from my Galaxy Nexus using Tapatalk 2


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## tiny4579 (Oct 21, 2011)

ITGuy11 said:


> A zip would be awesome!
> 
> Sent from my Galaxy Nexus using Tapatalk 2


Despite my desire to bring something new and helpful to the table, I decided against this because of the risk factor pointed out and if you have to do thus yourself you'll be more aware of the risks.

Sent from my Galaxy Nexus using Tapatalk 2


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## yarly (Jun 22, 2011)

tiny4579 said:


> Not checking the filesystem doesn't corrupt it. Yarly, can you answer why the nex 7 doesn't have this check option on if having it missing is so bad?


Because it has different hardware is a possibility. Can't compare apples to oranges. It's running fsck basically which is not only a check, but a repair. If you want a more firm answer, ask JBQ on the AOSP newsgroup why the VZW Gnexus includes it.

Although it was not the answer I was looking for, I did ask JBQ before about it and he basically said "proprietary binaries can make anything possible."


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## gnarlsagan (Jan 21, 2012)

Why wasn't this necessary on ICS?

I'd like to politely but strongly request a zip to flash. Maybe a pm if you don't want it out there? I don't at all appreciate my 5 year old laptop booting faster than my gnex.


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## tiny4579 (Oct 21, 2011)

gnarlsagan said:


> Why wasn't this necessary on ICS?
> 
> I'd like to politely but strongly request a zip to flash. Maybe a pm if you don't want it out there? I don't at all appreciate my 5 year old laptop booting faster than my gnex.


Ics didnt have an fstab.tuna or a filesystem check on data or cache. Unless im missing something it was nowhere in the ramdisk. This is also why i didnt see a problem with this mod.

it only boots slow if there are problems. I should not have created this thread to begin with. If you want this to happen learn how to unpack a ramdisk and do it. As much as my idea was disapproved I don't want to do it now.

Sent from my Galaxy Nexus using Tapatalk 2


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## cobjones (Jun 21, 2011)

I'm curious to why this is suck a huge deal.

This is no different that someone flashing something else, or modifying other system files.

Have a backup saved off the phone if you are daring. There are toolkits available for people that need them.

Edit: I guess you need to hold peoples hands. You know if they brick their phone than it is their problem. It would be different if the OP purposely put out a bad mod,but he hasn't.

Thanks tiny and don't let this discourage you.

I don't see why teaching people about this kind of stuff is bad.


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## tiny4579 (Oct 21, 2011)

yarly said:


> Because it has different hardware is a possibility. Can't compare apples to oranges. It's running fsck basically which is not only a check, but a repair. If you want a more firm answer, ask JBQ on the AOSP newsgroup why the VZW Gnexus includes it.
> 
> Although it was not the answer I was looking for, I did ask JBQ before about it and he basically said "proprietary binaries can make anything possible."


do you have the thread in the newsgroup where you asked or was it on twitter or another social media site? I think it'd be good to know from jbq why prior to making any kind of mod.

Sent from my Galaxy Nexus using Tapatalk 2


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## tiny4579 (Oct 21, 2011)

cobjones said:


> I'm curious to why this is suck a huge deal.
> 
> This is no different that someone flashing something else, or modifying other system files.
> 
> ...


thanks for the kind words. This is different in a way as it changes a key jellybean boot process. If this was intended by Google we shouldn't change it honestly. You know how the internet works. People will flash a mod with a disclaimer and blame the mod even though the disclaimer clearly states its risky.

Sent from my Galaxy Nexus using Tapatalk 2


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## yarly (Jun 22, 2011)

Sure, I can drop you the link if you wish to reply and hopefully get a more clear answer from him. I was kind of disappointed in the answer at the time, but I guess I could have worded it a little better as well. I meant nothing personal against you about the mod as some users will of course think regardless. I applaud your curiosity and seeking out answers rather than accepting things as they are, just sometimes when something gets posted like this, objectivity gets confused with bias or heavy-handedness by some users that can't understand why someone would cast doubt or a dissenting opinion.

If you ask him and he replies, let us know of course. I would like to have a better answer from him on it as we're pretty much in the dark as far as a an official an answer as to exact reason it was placed on the Nexus to begin with and the exact causes of how it gets triggered (filesystem corruption obviously, but why does the Nexus need it over others [hardware most likely, but why]). We all have good ideas of how it does and why, but hearing it from the source is always better.

Anyways, his reply to me was left here. Probably best to created a new thread in the AOSP building group though and see if he'll reply. If he does, let us know of course


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## tiny4579 (Oct 21, 2011)

I posted a new topic in Android Buildin on Google groups so we'll see. I hope my wording gets the answer I wanted. Hopefully it's that they forgot to remove it from testing (maybe?) but we'll see. Hardware on the Gnex vs N7 should be similar as far as nand though I wonder. I also wanted to mention that CM10 builds on GS3 doesn't have a fs check that I know of.

Sorry if this turned into a discussion thread from a howto.


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## tiny4579 (Oct 21, 2011)

JBQ wasn't aware of why grouper doesn't check and tuna does. I asked if he could check with anyone else that may know for me.

Can someone on a gsm nexus maguro check if the mount line in fstab.tuna has the check option for either or both /data and /cache.

Update: I posted to android-porting as JBQ recommended that'd be a better place for my answer.

Link here for the google group: https://groups.google.com/forum/?fromgroups=#!forum/android-porting


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## imnuts (Jun 9, 2011)

All Galaxy Nexus phones should be the same as all use the same boot.img.


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## tiny4579 (Oct 21, 2011)

imnuts said:


> All Galaxy Nexus phones should be the same as all use the same boot.img.


Thought so. You're right, boot.img kernels work fine on both phones. Never mind my request then lol. This also means the long boots due to checks would be similar for toro, maguro, and toroplus.


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## gnex99 (Oct 9, 2012)

This would be great if doesn't create any problems. Its easy for some people to say that its not that big a deal or it doesn't take that long etc. I can have many normal reboots in a row but then again I also have had 6+ reboots in a row where I have to wait the 2+ minutes before I see the boot animation. This is when I choose reboot from the power menu, hit turn off and turn the phone off later, etc. It should not run a file system check if nothing is wrong, and beyond that nothing should be wrong if I reboot an appropriate way. This is on all ROMs I've tried and even the OTA update from vzw...

OP have you had any issues by doing this? I don't know how to do this but will try to find out if its something I can figure out how to do because this has been extremely annoying on my phone. Yet my friend has the same phone and hasn't seen a single long boot yet.


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## Schoat333 (Jun 14, 2011)

This is interesting. I'd like to know the answer for this as well. I know JBQ did say the original JB Toro binaries were "experimental" so I guess I can see that being part of the reason.


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## legacystar (Jun 9, 2011)

My roommate has a gsm nexus and has never seen a long rebiot ever, while my Verizon nexus gets it all the time regardless of how I reboot. Explain that .


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## BarberAE (Feb 23, 2012)

I had the long reboot issue with my previous GNex which was a hardware revision 9 but just got a replacement that is hardware revision 10 and have no issues.


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## tiny4579 (Oct 21, 2011)

legacystar said:


> My roommate has a gsm nexus and has never seen a long rebiot ever, while my Verizon nexus gets it all the time regardless of how I reboot. Explain that .


I don't remember getting a long boot in a long time and I think it was since 4.1.2. Is anyone else the same way? Also, I don't do this mod anymore as I got a bootloop after a reboot a few weeks ago and had to reflash CM10 and wipe cache (this was at work so I didn't have time to check why or fix it). I think the mod disabling the filesystem check led to the problem and I haven't needed it on 4.1.2 that I know of so I don't do the mod.


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