[Galaxy S II Q&A, Help & Troubleshooting] colin.jones:
I have an issue with the size of the thumbdata3 file in DCIM/.thumbnails on internal memory (camera is set to store to ext SD) at the moment it is 314MB on internal memory but the thumbdata3 file in the DCIM/.thumbnail folder on ext SD is less than 1MB (I only have around 100 photos and pictures on my phone) - but camera still works (other than in the scenario described below)

If I delete the large thumbdata3 file from internal memory and then attempt to use the camera, the photo is taken without any problem but when I try to view it in either gallery or QuickPic by clicking through from the 'last image taken thumbnail' in the camera and then click back to carry on taking another picture the camera FC's. It usually does this twice and is then absolutely fine - apart from the fact that the large thumbdata3 file has been recreated on internal storage.

I've tried it numerous times and every time the same results - delete thumbdata3 from internal memory, couple of camera FC's, large thumbdata3 file recreated, no more problems (bar the loss of 314MB of storage) :confused:

I've tried replacing the thumbdata3 file on internal memory with a copy of the smaller one from Ext SD, creating a blank thumbdata3 file and setting it as read only/no write permission and neither have helped.

Its a bit weird and annoying but I won't let it take the shine off my fun with CM9, however it would be nice to recover that large chunk of storage space to be put to better use.

All the same, many thanks Arco - Beta 1 is my first CM9 install and its great :good:[/QUOTE]

Hi - haven't full troubleshooted this issue yet, but see my notes here. I have the same issue (GNEX JB 4.1.1 stock) and for me it is caused by the app KeepSafe which hides/unhides pics/videos on your phone. Note I believe this is an interaction issue between this app and the media scanning functionality in JB (and I suspect ICS), and so there are likely other apps that have the same issue. For me it creates 1 or 2 .thumbdata3 db files each around 1.3GB.

Certainly, irrespective of app causing it, you can follow the steps to purge Gallery and Media Storage, resync your gmail account and they should disappear on their own. Opening the camera and taking a photo causes the db to come back at around 400MB with a single thumbnail - one of the test files I was hiding and unhiding with KeepSafe but has since been deleted. Can't really explain this behaviour!

Any way, I made some notes on what I tested, the results and some ponderings in case this helps someone work it out:

Thumbdata3

Hiding in keep safe seems to create both the thumbnails and thumbdata file.

Clearing data/cache for gallery and media storage removes all these files? So far doesn't seem to be the case. File and db still there after. Rerunning the media scanner now. Perhaps they caused it? Also forced resync of all items in gmail account. Thumbs and db now gone. Not clear if it was the media scanning completing or the re-sync, but steps to resolve issue now appear deterministic.

Tested with single pic. Restored. No thumbs. Re-hid, thumbnail appeared for this pic and a 435MB db file.

All thumbs were for pics hidden in keep safe. However previously there were far more thumbs. Speculate - cumulative issue thru successive hide/restore cycles, possibly due to file name collision avoidance.

Deleting pic in file explorer also causes the problem? Does not appear to be the case. Gallery/Media Scanner/Media Storage handles this manual intervention far better under ICS/JB. Previously, manually removing a picture rather than deleting it thru Gallery tended to mean the tile/thumb remained. Scanner didn't or didn't very effectively detect this. Probable algorithm change in ICS. Now it sees the deletion immediately. Possibly implicated in keep safe not correctly interacting with the gallery/media scanner properly under ICS/JB.