[SOLVED] Can I properly enable OpenCL on Windows 11 and Intel Iris Xe graphics in Darktable 4.0?

[Ulrich_Staudinger]

Thanks Thanks Thanks.

[Chen_Hendrawan]

Hi all,

I’m testing the latest Windows development build by @wpferguson and I noticed that this issue is still present for Intel Iris Xe graphic.

I can workaround the issue by following the extract instruction below, however, what is required to include the official fix in the final release?

@litetaker

How to fix the issue with OpenCL not working on Windows with an Intel integrated graphics:
(As of Darktable version 4.0)

• Go to C:\Users\AppData\Local\darktable
• Open the darktablerc file. Search for already configured CL devices: these will have config keys starting with cldevice_
• Delete all the lines starting with cldevice_ to essentially delete already configured devices for OpenCL.
• Check if there is a already a line starting with opencl_disable_drivers_blacklist=. If so, add TRUE at the end or else, add a new line with opencl_disable_drivers_blacklist=TRUE
• Go to the Darktable bin folder where you will find darktable_cltest.exe. At the moment, due to a bug, you will have to run the following command twice to properly setup your integrated GPU to use OpenCL: darktable-cltest.exe -d opencl (if they incorporate my bug fix, then you only need to run this command once)
  • You probably don’t have to run darktable-cltest.exe but perhaps just open darktable and it may also setup OpenCL devices

[Chen_Hendrawan]

Okay I read further and found that the issue can simply be work around by changing a single setting from 1 to 0

From here: darktable 4.6 user manual - memory & performance tuning

h. disable device
0 = enable device; 1 = disable device
If darktable detects a malfunctioning device it will automatically mark it as such by setting this parameter to 1. If you have a device that reports a lot of errors you can manually disable it by setting this field to 1.

However, the question remains that why is the Windows NEO driver is still blacklisted despite there has been a bug fix that should have fixed the original issue.

What test on Windows can be done to prove that the blacklist can be removed?

[g-man]

@Chen_Hendrawan

why is the Windows NEO driver is still blacklisted despite there has been a bug fix that should have fixed the original issue.

Start an Issue in GitHub for Feature Request to remove the Neo as blacklisted for windows. Provide screenshots or some info that shows it working on your system with current drivers. Test using multiple heavy openCL modules (D&S). Without an issue and test data, it will remain blacklisted. I run windows, buy i don’t have an Intel, so i cant test it.

[hannoschwalm (Jens-Hanno Schwalm)]

@g-man

Start an Issue in GitHub for Feature Request to remove the Neo as blacklisted for windows. Provide screenshots or some info that shows it working on your system with current drivers. Test using multiple heavy openCL modules (D&S). Without an issue and test data, it will remain blacklisted

Absolutely! I think it would be far worse to remove it from blacklist and get lost of user complaints about dt crashing or doing other bad things than “just set one 1 to 0”. The mentioned “bug fix” was a fix but not the reason for blacklisting.

Another option would be: you could start a windows user survey about “How does NEO work?”

[Chen_Hendrawan]

The more I read about the issue the more I got confused. Before asking the devs via Feature Request or creating the poll, I want to get my facts straight first:

• So the NEO driver is just the open source OpenCL driver provided by intel? It is NOT the Windows specific version of it?
• I assume this driver is installed by the system in Windows and presumably in other OS too? I mean this driver is not compiled by darktable and included in the release?
• This NEO name covers not just a single specific Intel device but also some variants? e.g. Intel UHD, Intel Xe, Iris, whatnot?
• What is actually being blacklisted, was it the whole NEO driver, or combination of driver in specific device? Certain driver versions?
• Is it only blacklisted in Windows?

I’m asking because majority of Windows users will get the latest drivers from the Windows update. Assuming the latest driver is stable (which we can check via poll) we can just tell people to update their drivers. But can you remove the blacklist just for Windows build?

Edit:
As for the stability of the driver in my laptop. DT works fine with Intel NEO open CL enabled, running the Sigmoid, Colour Balance RGB, Diffuse & Sharpen, etc.

[g-man]

1. correct, it is Intel open source driver. The say they use the same codebase for the windows version of the drivers.
2. dt uses the drivers installed in the OS.
3. correct, neo is the driver code name used by multiple Intel devices.
4. the NEO driver is blacklisted
5. it is only blacklisted for windows (WIN32 in the code)

The change to remove it from the blacklist is very simple and can be done just for windows. The desire is to remove it from blacklist, but there needs to be enough evidence that it doesn’t cause issues to window users. Right now, you are the first one reporting that it works for you. A feature request in GutHub is the best way to track this. Post your detail system information (version of windows, drivers versions, etc). Others can then use your post to also post their results (in favor or against it).

Once enough folks comment, then it can be removed from master to give a wider set of test user to report issues before an official release (every 6 months).

[hannoschwalm (Jens-Hanno Schwalm)]

@Chen_Hendrawan

What is actually being blacklisted, was it the whole NEO driver, or combination of driver in specific device? Certain driver versions?

Blacklisting and non-blacklisting special combinations is a no-go for me as there is no way to check all cases.
We could offer some way to override blacklisting via preferences though for easier testing.

[rvietor]

@Chen_Hendrawan

I’m asking because majority of Windows users will get the latest drivers from the Windows update.

That depends on Microsoft. From what I’ve seen, the drivers provided by microsoft aren’t always the latest stable versions, but can lag significantly behind the versions published by the hardware manufacturer, Intel, in this case
(Understandable, as their main target audience probably doesn’t need the latest stable drivers, and every change means something can break).

[olliwa (Olivier)]

Hello, on win10 or win11 I experience that dt works faster without enabling opencl support.
Has anyone made the same observation?
for example :
win11 v10.0.22621
dt4.10+1065
11th Ge i7-1165G7 intel iris Xe Graphics driver 30.0.101.1003

[kofa (István Kovács)]

There can be several reasons:

• your CPU is very fast, the intel chip not
• the driver can be bad
• not enough GPU memory, causing tiling
• you use mandatory OpenCL processing and hit the opencl_mandatory_timeout. See OpenCL is mandatory, yet CPU is used (solved) - #4 by kofa and OpenCL is mandatory, yet CPU is used (solved) - #11 by kofa.

[sovereign (Matteo Costa)]

In my experience it is not stable yet. On Windows 11, 11th gen processor and the latest NEO drivers I had a few crashes in a couple of hours. I disabled OpenCL.

[sovereign (Matteo Costa)]

After some more testing I observed that it crashes whenever I try to enable highlights reconstruction in filmic and that using the color zones module produces artifacts in the blown highlights at export.