[Fascinate Q&A, Help & Troubleshooting] kirkers:
EXT4ALL (aka Convert2ext4) = final fix for dalvik cache related bugs (?)

Further investigation of the Dalvik cache reveals a significant connection between it and a number of odd and unpleasant behaviours, including Low Disk Space warnings and disappearing apps.

Fortunately, there are some excellent XDA forum threads about dealing with the Dalvik cache.

The best recent place to start seems to be here:

[Q] Incredible running CM7.2 "Low on space" message (launched 2012-12-14)

http://xdaforums.com/showthread.php?t=2047424

It is not because of the focus on the Droid Incredible or CyanoModGen in this thread, but the attention paid to the more universal fix "EXT4 4 ALL" aka "EXT4ALL" or "Convert2Ext4". (Thanks to Senior Member cmlusco for his post #9 on the thread that got me started in the right direction!)

Files can be found at these locations:

Goo.im site http://goo.im/devs/tiny4579/mods

DINC.does-it site http://dinc.does-it.net/EXT4_Mods/

One version of this fix (Convert2Ext4_no_data_limit_normal_dalvik.v2.0.zip) moves the Dalvik cache from the default, limited 150MB internal partition to the "unlimited" (or at least maximum) 750MB internal partition.

Any phone with a kernal installed that supports ext4 can utilise this fix.

[ I personally use gingertiny 2.6.35.14-v2+ (2012-02-13), which has supported ext4 since late 2011]

My own experience has been to flash the "no data limit normal dalvik" zip file using ClockworkMod 5.x Recovery -- this was entirely painless. I just downloaded the file into my phone's downloads folder on the sdcard using a web browser, then ran CM Recovery (with a little assist from ROM Manager), selected "install a zip from sdcard" and navigated to the file. It was all done in 5 minutes. After manually rebooting a second time, everything seems to be working normally after about half a day of regular use.

For those who flash a new or updated ROM sometime in the future, you would need to flash this fix after doing so.

There is plenty of information contained on the main threads of this topic. Links aplenty can be found; just follow the ones provided in the thread I suggest here to get started.

Hopefully, this brings an end to my struggles with my phone's storage issues, and to others of you reading this post and following the links to the threads and downloads.

FYI -- My storage values changed as follows after running the fix:

Total Internal memory: 748MB --> 770MB (22MB increase)

ROM free space: <1MB --> 20MB (close to the value change of total internal memory)

Used internal memory: ~335MB --> 464MB (close to 128MB increase)

Remaining internal memory: ~420MB --> 306MB (close to 128MB decrease)

So, it seems that my ROM was being used to cache app data, which would explain why the value kept declining even though I NEVER added anything to it (using Titanium Backup Pro or anything like it). When free space on my ROM literally ran out, Android OS hit the proverbial panic button and warned me to free 512kb minimum to allow Gmail to download new mail. Now, it has 20MB free (and will hopefully stay that way, since I NEVER intend to transfer anything into the ROM!) :D -- The internal memory usage jump of 128MB probably indicates the Dalvik cache.

SUMMARY:

1. Turning off "fast boot" in Android settings helps some, but it does not get to the heart of the issue. It will NOT make a Low Disk Storage warning go away.

2. Once you have a Low Disk Storage warning, you MUST uninstall enough apps to make it go away (keep track of what you take away, because you can reinstall them very soon!)

3. With no LDS warnings showing, flash the "Convert2ext4 no data limit normal dalvik" zip file. THIS APPEARS TO BE THE REAL SOLUTION!

4. Reinstall your recently removed apps, and you should be good to go! :fingers-crossed:

PS>>> One last unresolved issue: I am still unclear exactly WHERE the dalvik-cache ends up, since my Astro file browser cannot locate anything containing the word "cache" that does not now report "EMPTY". There are a large number of "com." folders containing software I have installed found in the /mnt/asec/ folder. The total size of the contents of this folder (362 MB) is within 100MB of the amount of internal memory reported in use. Does that 100MB represent the current size of the Dalvik cache files, or at least include them? If so, where are they located? If anyone can help me figure this bit out, I would be grateful! :fingers-crossed: