Yeah performance rating is fucked. I had 9 performance then went 80:30 on a strat battle and my performance dropped to 2. Then i went 9:7 on an EU battle and it went up to 8. Then i went 32:15 on an NA battle and it dropped down to 4 i think. Makes no fucking sense. Just went 5:15 on an Eu battle so I can't wait for 10 performance 
I know even in the past when performance was working (assuming it is actually broken now) some weird stuff would happen, since it took into account your performance average of the last ~15 battles you've participated in. So, let's say in the first battle you went 900:1, and in the second through fifteenth you went 1:2, perhaps that first battle carried your performance up to a 9, and then when that 900:1 ratio was replaced with a mere 80:30, you saw the performance drop to a 2. Also, keep in mind that for for each battle your performance is relative to your teammates. You can go 5:7 in a battle and see your performance increase if no one else on your team got any kills, so maybe in that 80:30 battle the kdr average was actually better than that, or very close to it, for your team as a whole. Finally, I'm fairly certain that missing a battle not only deducts points from your reliability, but also your performance, and it records you signing up and essentially getting a kdr of 0:0, which in most cases is pretty poor, obviously.
