WebOS Internals - User contributions [en]

MojoDB Partition Resize

2014-06-04T16:46:06Z

RichT23: Addling a link to the quota DB issue

== Introduction ==

If you use your webOS device frequently, you have probably encountered the "Application database full" error, and were confused by it. It is a very confusing error, and the remedies are equally confusing. The error suggests deleting data, but it isn't clear what data. I learned that it meant app data (such as emails, contacts, calendar events), and not media. Though, the amount of files that you have on your USB partition can play a factor, too. Unfortunately, the tricks to get this error to go away are very few and short-lived. As a result, you will be greeted with the next evil error. That error will force you to reset your device. In this process, you are required to sign back into your Palm profile and watch in horror as all of your apps re-download, all of your Preware apps gone, as if you got the device new.... Nasty.

Well, there is a solution (and no, I won't be trying to sell you some anti-aging cream, or miracle spray, so rest assured, I have tried this on my own Pre3).

== The Dirty Bits ==

webOS 2.0 came along and offered a new application data storage feature. It allowed you to store data in a database called db8. It is pretty magical, and allows apps to share data through permissions. But, this feature had one fatal flaw. It was placed on its own isolated partition. This is a great way to protect the data, to some extent, but it limits how much data you can have on your device. The partition is only 135MB in size... You can use that quickly if you have a ton of files on your USB partition (the media indexer uses this database to store the index of the files on the USB partition), a few email accounts syncing regularly and storing a large backlog, and Koto Player indexing your media... This partition is /var/db... We will resize it.

=== Notes ===

There are three partitions of interest in the webOS world that can hold some valuable data. There is /var/db (the application data store), /var/file-cache (this stores a cache of contact pictures, email attachements, and a few other things, but is generally less important), and /var itself. The one we will focus on now (that causes the most trouble) is /var/db. Later I may add notes to changing the sizes of the others.

==== FAIR WARNING ====

I have seen people on the webOSNation forums recommend deleting large text files from the /var/db partition that do not have a ".db" extension. DO NOT (let me repeat that '''DO NOT''') delete these files. They are database journal files. A journal is a small record of entries written to a database or filesystem that a data management system can look to in the event that it is abruptly and uncleanly shutdown. It allows the device to "replay" transactions (so to speak) if you, say, were to pull the battery because the device seemed frozen. Deleting these files can put the journal and database out of sync, and the results of that are pretty messy and require a few hours of patient database cleanup....

== Pre-Operation Warnings ==

As should always be noted, there is always a chance that something could go HORRIBLY wrong. As a result, I provide absolutely NO warranty of any kind. You are on your own. As always, backup your data (using whatever process makes you feel the most secure, whether it is just copying off a few beloved photos, or doing a full mem dump).

I have only tested this on webOS 2.2.4 on a Pre3. It should work on any webOS 2.0+ device (likely including a TouchPad). If you do this on some other type of device, please report back!

== Let's Go! ==

Basically, what you will do is shave some space off of your /media/internal partition, and hand that over to the application database. I went safe and did about 500MB for mine. "Memory is cheap", so why not? I'll give you the commands below.

You can check your current usage with this command:

<pre><nowiki>
df -h
</nowiki></pre>

I recommend getting your current usage (-h means "human"), then subtract about 512MB from it and use that number below when shrinking the media partition (My media partition was about 12.8G, so I just made it 12.2G, which gives me about 600MB available, and I enlarged my mojodb partition by 512MB, so I'll have a few MB leftover, which is fine since you may have to grow /var later on). Make sure that you have enough room to shrink your media partition! I recommend backing it up, and deleting anything to clear space if you need to.

<pre><nowiki>
## Shrink the media partition

# Need to stop the cryptofs process, or rather "pause" it
pkill -SIGUSR1 cryptofs

# Unmount the /media/internal partition
umount /media/internal

# Shrink the partition (Replace 12.2G with the amount of space you want to reduce to. I think that the partition is 12.8 by default?)
resizefat -v /dev/mapper/store-media 12.2G

# Reduce the logical volume (make the "physical" disk smaller) 12.2G is the **SAME** number as above.
lvreduce -L 12.2G /dev/mapper/store-media

# Remount
mount /media/internal

# Restart the cryptofs service
pkill -SIGUSR2 cryptofs

## Increase the Application Database

# Stop the MojoDB service
/sbin/stop mojodb

# Unmount the filesystem
umount /dev/mapper/store-cryptodb

# Extend the file system up
lvextend -L 512M /dev/mapper/store-mojodb

# Extend the encrypted size up
cryptsetup resize /dev/mapper/store-cryptodb

# Resize the underlying filesystem
resize2fs -f -p /dev/mapper/store-cryptodb

# Remount
mount /dev/mapper/store-cryptodb

# Restart the service
/sbin/start mojodb
</nowiki></pre>

It might be worth rebooting here, too. df -h should show that you have a roughly 512MB /var/db. The application database error should be in your past. :) The only time you may experience a serious error about the application database is if it happens to become corrupt...

== Further reading ==

If you are resizing your Partition like this you will most lickaly run into this problem next [[DB_quota_exceeded]], so for awareness it could be worth reading that page too.

== Future Looking ==

My goal is to add this feature to Tailor. What I really am considering is setting up the partition like /media/cryptofs. If you notice, it shares the same size attributes as /media/internal. That is because they are the same partition! /media/cryptofs is actually a special cryptofs partition ontop of /media/internal. I would think that one could do this to /var/db, too. This would give one the most flexibility over application installation, data storage, and media space.

DB quota exceeded

2014-06-04T16:42:23Z

RichT23: a little more infomation, should be nicer looking!

== Introduction ==

A Problem often encountered after completeation of the [[MojoDB Partition Resize]] process is user notice (amongst other smptions) that they can not send Email or text messages.

In the messages log (via command line its /var/log/messages, this is a large file so might be troublesome to open via internals) or in Lumberjack you will see errors including the text "db: quota exceeded".

You will also notice that the db files them self's are large, you can check in /var/db/main via command line or via internals.

Here you see that my objects.db is over 60Mb
root@PigeonHawkPre:/# ls -al /var/db/main/
drwx------ 2 root root 4096 Jun 2 23:57 .
drwxr-xr-x 5 root root 4096 Jun 3 02:24 ..
-rw------- 1 root root 24576 Jun 3 09:42 UsageDbName
-rw------- 1 root root 1 Dec 29 2011 _version
-rw------- 1 root root 45056 Jun 3 02:24 indexIds.db
-rw------- 1 root root 30490624 Jun 3 09:42 indexes.db
-rw------- 1 root root 69632 Jun 3 02:24 kinds.db
-rw------- 1 root root 71565312 Jun 3 09:42 objects.db
-rw------- 1 root root 16384 Jun 3 08:37 sequences.db
root@PigeonHawkPre:/etc/palm# ls -lh /var/db/main/
-rw------- 1 root root 24.0K Jun 3 09:42 UsageDbName
-rw------- 1 root root 1 Dec 29 2011 _version
-rw------- 1 root root 44.0K Jun 3 02:24 indexIds.db
-rw------- 1 root root 29.1M Jun 3 09:42 indexes.db
-rw------- 1 root root 68.0K Jun 3 02:24 kinds.db
-rw------- 1 root root 68.3M Jun 3 09:42 objects.db
-rw------- 1 root root 16.0K Jun 3 08:37 sequences.db

== The size of the database is restricted ==
There is a quota on the size the database can reach its set in "/etc/palm/mojodb.conf"
# cat /etc/palm/mojodb.conf
...
"quotas" : [
{"owner":"*","size":20971520},
{"owner":"com.palm.*","size":78643200}
],
...

I wanted to increase the size of mine to 128Mb 128*1024*1024 = '134217728'

Via a commandline edit the max size of your database:

I'm my case I changed the "78643200" to "134217728"

so my Quota now looks like this:

# cat /etc/palm/mojodb.conf
...
"quotas" : [
{"owner":"*","size":20971520},
{"owner":"com.palm.*","size":134217728}
],
...

the just restart the mojodb (to be safe you should probably restart your device)

# Stop the MojoDB service
/sbin/stop mojodb

# Start the MojoDB service
/sbin/start mojodb

DB quota exceeded

2014-06-03T10:01:43Z

RichT23: DRAFT

Portal:Accessing Linux

2014-04-08T19:59:19Z

RichT23: Adding a link to the Archive download page

This page is currently available in two languages:
:[[Image:Australia.png]] [[Image:USA.png]] [[Portal:Accessing Linux]]
:[[Image:China.png]] [[Portal:Accessing Linux-ZH]]

__notoc__
{{portal-one-column-blue
|header=Accessing Linux on the Pre or the Pre Emulator
|column1=
The Palm Pre is a Linux based device. Palm provides a simple method to access Linux running on the Pre or the Pre Emulator. A terminal program called ''novaterm'' is bundled with the freely available SDK, enabling command line access to your device (see below for instructions).

Once you have command line access to Linux, everything else is a process of installing a ''community standard library'' of Linux programs so that users have the same tools and options available to them. (For example, you can [[OpenSSH_Install|install openssh]] or [[Dropbear_Install|dropbear]] enabling shell access to your device.) Once this is process is completed, pretty much anything you can do on a Linux box you can also do on the Pre or the Pre Emulator.

Notice, that the described procedure below is not compulsorily necessary for you to just install further linux software packages to your device. The [[Application:Preware|Preware]] application manager (an app you install to your device) is capable of installing these as well.

The following procedures will walk you through the process of obtaining initial command line access to Linux via novaterm on the Pre or the Pre Emulator, and installing the community standard software packages. The same instructions apply to the Pixi as well.

}}

{{portal-two-columns
|column1=
== Before you start ==

Please make a note of this page: [[How To Recover]]

If you are unfamiliar with basic Linux command usage, you should visit this page: [[Basic_Linux_Use|Basic Linux Use]]

===Disclaimer===
Enacting any set of instructions from this site has the (remote, but greater than zero) potential to void your warranty. Our intention and the specific design of all instructions is such that you should be able to recover using the [http://www.palm.com/ROM webOS Doctor] should anything go wrong, and put your Pre back to a state which is indistinguishable from a factory-new Pre, but we give no guarantee. Use any information from this site at your own risk. At the very least, you should be prepared to lose all data on your phone at any time. We cannot tell you what you should do - we provide the information, but it's up to your own sense of personal responsibility to determine what you do with that information. '''We require you to use the [http://www.palm.com/ROM webOS Doctor] to put your Pre back to factory condition before contacting Palm or your cellular carrier for service or support.'''

You might also want to consider backing up any files you have in the usb drive portion of the Pre.
|column2=
== Procedure: ==

In general, simply installing the Palm SDK gives you everything you need for full access to the Linux operating system on the Pre or Pixi. There is no special "rooting" or "jailbreaking" process. Simply installing the SDK provides you with unlimited access to the Linux operating system logged in as the root user. Palm does not see this as a bad thing. '''Palm''' provides all these tools for download by anyone, anytime, for free.

# Download the [http://developer.palm.com/index.php?option=com_content&view=article&layout=page&id=1788&Itemid=321# Palm SDK].
# Install it using the installation instructions for [http://developer.palm.com/index.php?option=com_content&view=article&layout=page&id=1545&Itemid=55 Mac], [http://developer.palm.com/index.php?option=com_content&view=article&layout=page&id=1585&Itemid=55 Linux], or [http://developer.palm.com/index.php?option=com_content&view=article&layout=page&id=1661&Itemid=55 Windows]. These links to the Palm site point to a page with broken download links, some older still working links are available on the Web Archives version of this page [https://web.archive.org/web/20121023072516/https://developer.palm.com/content/resources/develop/sdk_pdk_download.html Web Archive Page]
# Enable dev mode on your Pre:
## In Card view or in the Launcher application, type the following: webos20090606
## Tap the resulting Developer Mode Enabler icon.
## In the application, move the Developer Mode slider to the On position.
## Tap Reset the Device .
##* When reset is complete, Developer mode is enabled.
# Plug the device into the computer via the USB cable, and select "Charge only."
# The next step varies:
#* On Mac or Linux, type '''novaterm''' in a command (terminal) window to directly access the Linux command line.
#* On Windows you will need to download and install a novaterm program.
#** On 32 bit Windows download [http://tkgeisel.com/stuff/novaterm-1.zip novaterm1.zip] and unzip it into the \program files\palm\sdk\bin directory.
#** On 64 bit Windows download [http://vocshop.com/stuff/novaterm64.zip novaterm64.zip] and unzip it into the \program files\palm\sdk\bin directory.
#**Then, just like the Mac and Linux users you can just type '''novaterm'''.

'''At this point you will have a window with a prompt that says root@webos-device: or something similar.

You are now logged in as root on your webOS device and can do anything you would normally do on a Linux device.

Please be careful, you can seriously bork your phone now. '''

'''IMPORTANT NOTE:'''
With the addition of the ability to install Optware packages to Preware, unless you have a need or desire to type commands into the native Linux shell of your Palm device, there is no need to use the novaterm terminal to log into your devices. ''' Webos Quick Install''' (a java program for your desktop) and '''Preware''' (an app to run on your device) '''are fully capable of installing any Optware IPK (including *.patch and *.diff) to Palm devices'''. Linux command line access is needed by very few people. If you came here from a web page that talked about "root access" or "rooting your Pre" be aware that most of the instructions which require root access have been superseded.

}}
{{portal-two-columns
|column1=
== Advanced Topics ==

* [[Adding Disks to the Emulator]]
* [[Backing_Up_via_Rsync|Backing Up via Rsync]]

|column2=
== Next Steps ==

* [[Tutorials_Linux_DDNS_for_EVDO|DDNS for EVDO]]
* [[Next_steps|Set up users, Optware, and access]] '''DEPRECATED'''
* [[Applying_Patches|Applying Patches]] '''DEPRECATED'''
* [[Setup_SFTP|Setup SFTP]] '''DEPRECATED'''

}}