Can't force the detection of OpenCL devices #73734

New Issue

Kévin B · 2020-02-11T17:31:09+01:00

Kévin B commented

2020-02-11 17:31:09 +01:00

Blender Version
Broken: maybe since 2.80?

Short description of error
At some point it was possible to force an OpenCL device to be picked up with CYCLES_OPENCL_SPLIT_KERNEL_TEST=1 in the environnement but it's apprently gone. I can see in opencl_util.cpp:861 that a flag exists for that very reason but it seems it was never implemented, could it be possible to set that flag to true with an option/env variable?

**Blender Version** Broken: maybe since 2.80? **Short description of error** At some point it was possible to force an OpenCL device to be picked up with `CYCLES_OPENCL_SPLIT_KERNEL_TEST=1` in the environnement but it's apprently gone. I can see in [opencl_util.cpp:861 ](https://developer.blender.org/diffusion/B/browse/master/intern/cycles/device/opencl/opencl_util.cpp$861) that a flag exists for that very reason but it seems it was never implemented, could it be possible to set that flag to true with an option/env variable?

Kévin B commented

2020-02-11 17:31:09 +01:00

Added subscriber: @Tzig

Ray molenkamp commented

2020-02-11 17:59:13 +01:00

Added subscribers: @Jeroen-Bakker, @brecht, @LazyDodo

Ray molenkamp commented

2020-02-11 17:59:13 +01:00

I have to admit, this has annoyed me for the longest time as well, previously it was still possible to test opencl on nvidia using the cycles debug menu, but that has broken somewhere as well during one of @Jeroen-Bakker 's refactors somewhere during 2.80.

which makes testing kernel changes more annoying than it should be , can we restore the functionality of the debug menu to either it's former glory or decide we don't care and remove the dead options from it

cc: @brecht

I have to admit, this has annoyed me for the longest time as well, previously it was still possible to test opencl on nvidia using the cycles debug menu, but that has broken somewhere as well during one of @Jeroen-Bakker 's refactors somewhere during 2.80. which makes testing kernel changes more annoying than it should be , can we restore the functionality of the debug menu to either it's former glory or decide we don't care and remove the dead options from it cc: @brecht

Germano Cavalcante commented

2020-02-12 12:56:16 +01:00

Added subscriber: @mano-wii

Germano Cavalcante commented

2020-02-12 12:56:16 +01:00

We no longer have the opencl mega kernel 949ab753bb
The kernel is splitted by default.

I don't understand the difference that this option would make. (We can't just bring the mega kernel back).

We no longer have the opencl mega kernel 949ab753bb The kernel is splitted by default. I don't understand the difference that this option would make. (We can't just bring the mega kernel back).

Aaron Carlisle commented

2020-02-20 05:19:40 +01:00

Changed status from 'Needs Triage' to: 'Confirmed'

soulfire commented

2020-03-03 19:22:16 +01:00

Added subscriber: @TomG

soulfire commented

2020-03-03 19:22:16 +01:00

Could you re-enable AMD 7870HD series for Cycles/OpenCL which were deprecated in Blender 2.78?

Could you re-enable AMD 7870HD series for Cycles/OpenCL which were deprecated in Blender 2.78? ![yuiotzghdf.JPG](https://archive.blender.org/developer/F8385637/yuiotzghdf.JPG)

Brecht Van Lommel commented

2020-03-03 19:37:07 +01:00

We are unlikely to bring back support for cards that were deprecated. I don't think the reason behind that decision has changed as the graphics card has not received driver updates for quite a while.

soulfire commented

2020-03-04 05:58:31 +01:00

In #73734#884530, @brecht wrote:
We are unlikely to bring back support for cards that were deprecated. I don't think the reason behind that decision has changed as the graphics card has not received driver updates for quite a while.

There was a glitch when rendering hair and microdisplacement with OpenCl on that card. Everything else worked.

> In #73734#884530, @brecht wrote: > We are unlikely to bring back support for cards that were deprecated. I don't think the reason behind that decision has changed as the graphics card has not received driver updates for quite a while. There was a glitch when rendering hair and microdisplacement with OpenCl on that card. Everything else worked.

blender-admin commented

2020-03-21 18:55:45 +01:00

This issue was referenced by blender/cycles@6b063eb75f

This issue was referenced by blender/cycles@6b063eb75f6895cd4592bd739adffe90ecaa5de9

Ray molenkamp commented

2020-03-21 18:57:43 +01:00

I brought back the environment variable in D7202 to enable testing on unsupported hardware, leaving this ticket open though since the debug menu should still be either fixed or removed.

I brought back the environment variable in [D7202](https://archive.blender.org/developer/D7202) to enable testing on unsupported hardware, leaving this ticket open though since the debug menu should still be either fixed or removed.

Thomas Dinges commented

2021-11-18 20:28:55 +01:00

Added subscriber: @ThomasDinges

Thomas Dinges commented

2021-11-18 20:28:55 +01:00

Changed status from 'Confirmed' to: 'Archived'

Thomas Dinges closed this issue

2021-11-18 20:28:55 +01:00

Thomas Dinges commented

2021-11-18 20:28:55 +01:00

OpenCL rendering support was removed in Blender 3.0.
The combination of the limited Cycles kernel implementation, driver bugs, and stalled OpenCL standard
has made maintenance too difficult. Thanks for all your reports, but it's unlikely that there will be further fixes for OpenCL.

For AMD GPUs, there is a new backend based on the HIP platform.
In Blender 3.0, this is supported on Windows with RDNA and RDNA2 generation discrete graphics cards.
It includes Radeon RX 5000 and RX 6000 series GPUs. Driver version Radeon Pro 21.Q4 or newer is required.

https://wiki.blender.org/wiki/Reference/Release_Notes/3.0/Cycles
https://code.blender.org/2021/11/next-level-support-for-amd-gpus/

OpenCL rendering support was removed in Blender 3.0. The combination of the limited Cycles kernel implementation, driver bugs, and stalled OpenCL standard has made maintenance too difficult. Thanks for all your reports, but it's unlikely that there will be further fixes for OpenCL. For AMD GPUs, there is a new backend based on the HIP platform. In Blender 3.0, this is supported on Windows with RDNA and RDNA2 generation discrete graphics cards. It includes Radeon RX 5000 and RX 6000 series GPUs. Driver version Radeon Pro 21.Q4 or newer is required. https://wiki.blender.org/wiki/Reference/Release_Notes/3.0/Cycles https://code.blender.org/2021/11/next-level-support-for-amd-gpus/

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Can't force the detection of OpenCL devices #73734