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From: Richard Weinberger <richard@nod.at>
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Date: Wed, 22 Jun 2016 21:56:39 +0200
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Hi!

Am 22.06.2016 um 17:26 schrieb »ΤΙΩ:
> Thank you for kind reply.
> 
> 1. As you said just now"there is only a background thread to do many things",  dose "many things" include both GC and synchronizing data?

I said GC can happen in many contexts. Also in the calling one.
To figure what the background thread exactly does see function ubifs_bg_thread().

> 2. If I write a file(1 KB) to ubifs mounted in 34MiB mtd, can i write 34,000 times or 34000/4 times(the real disk usage of a 1KB file is 4KB)£Ώ

The minimal file size on UBIFS is 4KiB. You can also not use all 34MiB, since UBIFS needs some LEBs for the journal, free space accounting,
master nodes, etc...

Thanks,
//richard