Am 01.07.2016 um 16:55 schrieb »ΤΙΩ:
> 1. You mean in async mode file is written to flash by writeback mechanism? If so, background thread has nothing to do with writing file to flash? 

I'd not say nothing, it does the commit.

> 2. In sync mode, is writting finished by ubifs background thread or calling thread calling write()?

The calling thread.

Please start reading the UBIFS source code.

Thanks,
//richard