Thanks for publishing these results.
I noticed that btrfs has an SSD mode now:
https://btrfs.wiki.kernel.org/index.php/FAQ#Is_Btrfs_optimized_for_SSD.3F
Did you use one of the SSD options when you mounted the btrfs partition for these tests?

Python, BASH, PHP and JavaScript programmer, Linux fanatic user, and uber-geek.
My name is Piotr Gabryjeluk. I currently work at Allegro Group. I worked at Wikidot.com and several other companies.
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