[Galaxy S Plus I9001 Android Development] Christopher83:
FAQ - Frequently asked questions:

Q: What are the differences between EXUV and UV kernel versions?

A: The EXUV kernel versions have extremely undervolted settings for the cpu frequencies, they allows to have a very low battery drain, instead the UV kernel versions have undervolted settings a bit higher than EXUV versions, but always lower than stock kernel settings.

The EXUV kernel versions could give some problems (freezes, shutdowns, huge lags) on some devices because the cpu doesn't support too low voltage settings.

For a lower battery consumption, I suggest you to try EXUV versions first and to switch to UV versions only if you encounter one of the above mentioned problems.

Q: For kernel v2.0 and before, what are the differences between 398MB, 406MB and 416MB versions?

A: 398MB, 406MB and 416MB kernel versions have different free ram available for user space, with a higher free ram your device will work better with heavy apps, many concurrently used apps, heavy games, etc.

- 398MB versions have the same amount of free ram than stock kernels, they are more stable, everything is fully working, but you could have some slowdowns with apps that require a high amount of free memory.

- 406MB versions have additional 8 MB of free ram than stock kernels (that memory has been taken from SurfaceFlinger reservation), they are suitable for the users that use the device primarly for calls, messages, simple apps and simple games. The camera, video recording (both 480p and 720p modes) and video playback are fully working.

- 416MB versions have additional 18 MB of free ram than stock kernels (that memory has been taken from SurfaceFlinger reservation), they are suitable for the users that use the device also with heavy apps, various concurrently used apps and games. The camera, video recording (both 480p and 720p modes) and video playback are fully working.

Q: How can I get the Performance and Developer Options entries inside Settings menu?

A: Go inside Settings -> About Phone -> Scroll down and tap 7 times on Build number (it's an Easter Egg).

Q: How can I get the log after an unexpected shutdown / reboot?

A: After an unexpected shutdown / reboot of the device, if the problem may be kernel related, you should have the /proc/last_kmsg, if so, send me that log and I'll check it to find the possible cause of the problem.

Q: How can I get the logs when I encounter strange system issues while it's running?

A: Check first if the problems could be related to an app you're using and if you changed something in the last days before facing those issues.

If the problem started after installing the kernel, then let me have you logcat and dmesg:

- Open Terminal Emulator and execute these commands:

su
dmesg > /sdcard/dmesg.txt
locat -v time -d > /sdcard/logcat.txt

- Open you preferred file manager and go inside the internal sd card partition /sdcard

- Send me the dmesg.txt and logcat.txt files, if you want zip them first

Q: What is F2FS file system?

F2FS (Flash-Friendly File System) is a new file system designed for delivering maximum file-system performance on flash-based storage devices. For more info: F2FS

Q: How can I switch to F2FS format type for /data partition without loosing data?

By switching from EXT4 to F2FS format type for /data partition, without performing any backup, you will surely lost all your user data files and internal sd content.

To avoid that, follow these steps:

- Perform a backup of your internal sd (/sdcard) by copying the /sdcard content inside a new folder on /external_sd or on your pc (through MTP)

- Reboot into recovery

- Install latest TWRP recovery with F2FS support

- Reboot -> Recovery to reboot inside the newly installed recovery

- Perform a full backup of your current configuration, inside Backup -> Flag all partitions -> Set a customized name if you want -> Set Micro SD card as storage -> Swipe to Backup

- After the backup process has completed, go inside Wipe -> Advanced Wipe -> Select Dalvik Cache, System, Cache -> Swipe to Wipe

- Always inside Wipe -> Advanced Wipe -> Select Data -> Repair or Change File System -> Change File System -> F2FS -> Swipe to Change

- Install new rom and gapps

- Restore your data partition from previously made backup, Restore -> Select latest backup -> Select Data only -> Swipe to Restore (don't care about ext4 warnings)

- Restore your /sdcard backup

- Reboot System

- Check if your data is using F2FS format type by running the following command inside Terminal Emulator or through ADB:

mount | grep f2fs

If everything is ok, you should get

/dev/block/mmcblk0p28 /data f2fs <various comma separated options>

Q: How can I mount a shared Windows folder with CIFS module?

1) By using Terminal Emulator

mount -o unc=\\\\[COLOR="DarkGreen"][I]ip[/I][/COLOR]\\[COLOR="Blue"][I]share[/I][/COLOR],noserverino,username=[I][COLOR="DarkOrange"]user[/COLOR][/I],password=[I][COLOR="Lime"]password[/COLOR][/I] -t cifs //[COLOR="DarkGreen"]ip[/COLOR]/[COLOR="Blue"]share[/COLOR] [I][COLOR="DarkSlateGray"]/mnt/cifs[/COLOR][/I]

2) Downloading and using CifsManager and configuring the new share as follow:

- Share Path = ip/share

- Mount Point = /mnt/cifs/share

- Username = username

- Password = password

- Options = unc=\\\\ip\\share,noserverino

Where:

ip is the ip address of your pc where the folder is shared

share is the shared folder name

user is the user name that can access the shared folder

password is the user password

/mnt/cifs is the mount point (must be created if you'd like to use the command approach with Terminal Emulator)