background garbage collection in UBIFS

[Jagadish Bihani]

Hello,

Referring to the following link:
http://www.linux-mtd.infradead.org/faq/ubifs.html#L_bgt_thread

I came to know that background garbage collection is not implemented in 
UBIFS.
I  want to know that whether the latest release of UBIFS contains background
garbage collection.

The work which I am doing for my M. Tech project depends on it. If it is 
not implemented,
would you please advise me that how much time it may take for a single
person with no prior experience to implement it  and level of difficulty 
etc.?

Thanks and Regards,
Jagadish