RADV Lands VK_PIPELINE_CREATE_DISABLE_OPTIMIZATION_BIT

[phoronix]

Phoronix: RADV Lands VK_PIPELINE_CREATE_DISABLE_OPTIMIZATION_BIT

The RADV Vulkan driver within Mesa has landed its VK_PIPELINE_CREATE_DISABLE_OPTIMIZATION_BIT support so applications/games can opt to disable optimizations when compiling a Vulkan pipeline. This is notably what was just covered the other day for helping to reduce stuttering with DXVK...

http://www.phoronix.com/scan.php?page=news_item&px=RADV-CREATE_DISABLE_OPT_BIT

[shmerl]

Neat idea to trade some performance for reduced compilation time temporarily. How much does performance decrease when optimizations are off though?

[VikingGe]

How much does performance decrease when optimizations are off though?

Right now the effects on both pipeline compile times and runtime performance are negligible, and while i'm working on merging my code into the main branch, it'll be disabled by default. As of right now, it's just not worth using.

That said, Nvidia might eventually implement support for this flag as well.

[geearf]

Right now the effects on both pipeline compile times and runtime performance are negligible, and while i'm working on merging my code into the main branch, it'll be disabled by default. As of right now, it's just not worth using.

Are changes needed on your side or mesa to make it worth it?

[smitty3268]

Are changes needed on your side or mesa to make it worth it?

It appears that most of the time is spent inside the LLVM backend, but it's not trivial to speed that up so it doesn't sound like it will happen anytime soon.

[geearf]

It appears that most of the time is spent inside the LLVM backend, but it's not trivial to speed that up so it doesn't sound like it will happen anytime soon.

Oh I see, another LLVM blocker :/

Thanks!