By Luck, Marek Discovers A "Serious Performance Fix" For RadeonSI

[trek]

it is interesting to note the old r600 driver was already doing this way and the comments say:

When alpha test is enabled we can't trust the hw to make the proper decision on the order in which ztest should be run related to fragment shader execution.

If alpha test is enabled perform early z rejection (RE_Z) but don't early write to the zbuffer. Write to zbuffer is delayed after fragment shader execution and thus after alpha test so if discarded by the alpha test the z value is not written.

If ReZ is enabled, and the zfunc/zenable/zwrite values change you can get a hang unless you flush the DB in between. For now just use LATE_Z.

If alpha test is enabled perform z test after fragment. RE_Z (early z test but no write to the zbuffer) seems to cause lockup on r6xx/r7xx

[theriddick]

Keep it up Marek, I'm confident AMD can get their drivers performing on par with NVIDIA in due time. Once that happens I will definitely consider switching back to team red (already considering Zen next year).

[karolherbst]

"Team red"

:-$ ... Please dont use such terms, please?

[karolherbst]

Except you really want to be made fun of, then it is totally fine

[brent]

Has anyone done any testing?

[theriddick]

"Team red"

:-$ ... Please dont use such terms, please?

lol, No.

[ElectricPrism]

lol, No.

I second this. Also, Linux GPU wars is my version of a sports game, also if people are't cheering on both sides then the cause just becomes boring and everyone eventually stops caring. Linux Drivers are far too important to let go quietly without making some notice and acknowledging how fscking awesome the improvements are!

[theriddick]

I have two 980Ti atm in SLI, so I sort of go for both teams. Honestly I have not been impressed with the SLI performance in Fallout4 (I'll get around to testing others) so if a good single video card comes out from AMD I will definitely go for it. I would have got a Fury X if 8GB versions existed, but they don't...

[Chol]

To be fair you have to consider that the regression was introduced by Marek himself: https://cgit.freedesktop.org/mesa/me...a13813de221fc2

Also, there was a bug report pointing to that commit, which was ignored for 7 months: https://bugs.freedesktop.org/show_bug.cgi?id=94354

[karolherbst]

I second this. Also, Linux GPU wars is my version of a sports game, also if people are't cheering on both sides then the cause just becomes boring and everyone eventually stops caring. Linux Drivers are far too important to let go quietly without making some notice and acknowledging how fscking awesome the improvements are!

... that wasn't my point? I was just making fun of the term "team read", nothing else. I would never say "team green" either, because .... you know... except if it is obviously meant as a joke, then it is all fun and games.

But maybe I am taking too many things too serious on the internet, so maybe it is just me.