[Samsung Galaxy Gio GT-S5660] TripleRipple:
Based on my last post I have a few new questions. After performing some more testing (trial by fire/trial and error) with CWM I am not sure that I really understand the support of CWM 5.0.2.7 RFS and EXT4 file system as mentioned in my last post.

Typically before I perform a backup of a ROM (in this case the stock ROM which is RFS filesystem based) I perform the following procedure in CWM regardless of the version of CWM

1. wipe data/factory reset

2. wipe cache partition

3. go to advanced menu

4. Wipe Dalvik Cache

5. Wipe Battery Stats

6. Main Menu -> backup and restore

7. Backup

Questions:

1. Is that the correct procedure? Could some steps be left out or added? What is the safest most reliable way? Should I even use those steps before I perform a backup or are they only really to be used when you are having problems? These are all really the same question presented in different ways.

2. If I am using CWM 5.0.2.7 (supports both RFS and EFS) and I perform the wipe data/factory reset, I see that it is Formatting /data /cache /sd-ext etc on the screen. Also with the wipe cache partition option I see Formatting /cache displayed on the screen. When using these functions in CWM 5.0.2.7 does this format the phone for those partitions from RFS to EXT4?

I am beginning to agree with Darkshado's comment

However if anyone else has done some extensive testing and know the answer to this....then I can move on and stop using tools. I believe that some of the tools are suppose to work and perform a certain operation but do the opposite or not what is claimed or do not explain the functions well enough for me to understand what operation does what. I want to understand....not just do.

The reason I am asking is that when I try to run a restore of an RFS (stock ROM) backup that was preformed in CWM 5.0.2.6 (only RFS supported) or a backup from CWM 5.0.2.7 (supports RFS and EXT4) after performing the above procedures within CWM 5.0.2.7, it always fails with the

dreaded (E:format_volume: format_rfs_device failed on /dev/block/stl12 Error while formatting /system!) error. This is of course after flashing via Odin back to the stock RFS based ROM GT-S5660M_BMC_S5660MUGKG3_S5660MUGKG3_S5660MBMCKG3 from sammobile.com and then entering stock recovery mode and installing CWM 5.0.2.7.

Does CWM 5.0.2.7 change the stock Kernel on my phone to one that supports RFS and EXT4? My assumption is yes but it would be nice to know for sure.

Based on my testing and findings so far I can tell right now that 5.0.2.7 is more EXT4 based then RFS. It will read RFS files and install on an RFS based filesystem (Stock ROM) and it will even make good backups of the RFS system. However it will not restore those RFS backups regardless if they were made in CWM 5.0.2.6 or CWM 5.0.2.7. Now if you flash back to stock ROM again via ODIN and install CWM 5.0.2.6 only RFS supported, you can restore backups of RFS based file systems backups( on a stock ROM system) made in either CWM 5.0.2.6 or CWM 5.0.2.7.

So the verdict is again (finding out the hard way)....DarkShado and AvrX are indeed correct. Use CWM 5.0.2.6 for backups and restores of Stock ROM.

For custom ROMs...which are predominantly EXT4 based now...I guess you need to use 5.0.2.7....but I will use the soley EXT4 based one from now on as the RFS & EXT4 based one I believe is limited. The only thing is if you install the 5.0.2.7 EXT4 only supported version, you will need to use the EXT4 Formatter (installed via CWM) before to make everything work properly before playing with EXT4 based Custom ROMs. Unless EXT4 formatting is built into the installer like it is with enhanced236_06.08.2012.

Morale of the story is again Darkshado is correct in what he was implying....what I am trying to accomplish is "Neat?" "Worth the Trouble"....My answer now...is a "NO".

None of the current versions of CWM "Fully" (read and write) support RFS and EXT4 at the same time and allow you to return to the stock based RFS backup plus play with EXT4 based new Custom ROMs. I know about the EXT4 Formatter....does anyone know of RFS Formatter tool that installable via CWM?

That tool might accomplish what I would like to achieve. Then it really is only a matter of the procedure to follow to make it all work within CWM. Just have to switch between CWM 5.0.2.6 and CWM 5.0.2.7.

Thanks for following the thread and reading my "trial and error" findings. I may perform a summary of my current findings in this post. It would be be a reply to my questions in the first post with the answer to my own questions. However I think I will wait to see if anyone is interested in providing any further comments.