[Gimp-user] How to tell if OpenCL is active and how to disable it?

[Nafspa <nafspa posteo de>]

Hi.

I now had my notebook two times freezing already when editing images in 
GIMP. The UI of the whole OS got unresponsive all of a sudden and only 
turning off and on the machine made it work again. I am not sure if this 
is in fact an issue with GIMP or it only happened by coincidence.

My notebook is a T495 with a Ryzen 3500U with integrated graphics card 
and Ubuntu 21.04. GIMP is installed in version 2.10.22 (installed from 
the Ubuntu software repository).

uname -a
Linux t495 5.11.0-18-generic #19-Ubuntu SMP Fri May 7 14:22:03 UTC 2021 
x86_64 x86_64 x86_64 GNU/Linux

gimp -v

GNU Image Manipulation Program version 2.10.22
git-describe: GIMP_2_10_20-217-g0c8a7891f7
Build: unknown rev 0 for linux
# C compiler #
    Using built-in specs.
    COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/10/lto-wrapper
    OFFLOAD_TARGET_NAMES=nvptx-none:amdgcn-amdhsa:hsa
    OFFLOAD_TARGET_DEFAULT=1
    Target: x86_64-linux-gnu
    Configured with: ../src/configure -v --with-pkgversion='Ubuntu 
10.2.1-23ubuntu1' --with-bugurl=file:///usr/share/doc/gcc-10/README.Bugs 
--enable-languages=c,ada,c++,go,brig,d,fortran,objc,obj-c++,m2 
--prefix=/usr --with-gcc-major-version-only --program-suffix=-10 
--program-prefix=x86_64-linux-gnu- --enable-shared 
--enable-linker-build-id --libexecdir=/usr/lib 
--without-included-gettext --enable-threads=posix --libdir=/usr/lib 
--enable-nls --enable-bootstrap --enable-clocale=gnu 
--enable-libstdcxx-debug --enable-libstdcxx-time=yes 
--with-default-libstdcxx-abi=new --enable-gnu-unique-object 
--disable-vtable-verify --enable-plugin --enable-default-pie 
--with-system-zlib --enable-libphobos-checking=release 
--with-target-system-zlib=auto --enable-objc-gc=auto --enable-multiarch 
--disable-werror --with-arch-32=i686 --with-abi=m64 
--with-multilib-list=m32,m64,mx32 --enable-multilib --with-tune=generic 
--enable-offload-targets=nvptx-none=/build/gcc-10-p9aljy/gcc-10-10.2.1/debian/tmp-nvptx/usr,amdgcn-amdhsa=/build/gcc-10-p9aljy/gcc-10-10.2.1/debian/tmp-gcn/usr,hsa 
--without-cuda-driver --enable-checking=release --build=x86_64-linux-gnu 
--host=x86_64-linux-gnu --target=x86_64-linux-gnu 
--with-build-config=bootstrap-lto-lean --enable-link-mutex
    Thread model: posix
    Supported LTO compression algorithms: zlib zstd
    gcc version 10.2.1 20210312 (Ubuntu 10.2.1-23ubuntu1)

# Libraries #
using babl version 0.1.86 (compiled against version 0.1.86)
using GEGL version 0.4.28 (compiled against version 0.4.28)
using GLib version 2.68.1 (compiled against version 2.67.5)
using GdkPixbuf version 2.42.2 (compiled against version 2.42.2)
using GTK+ version 2.24.33 (compiled against version 2.24.33)
using Pango version 1.48.2 (compiled against version 1.48.2)
using Fontconfig version 2.13.1 (compiled against version 2.13.1)
using Cairo version 1.16.0 (compiled against version 1.16.0)


In /var/log/syslog I find the following for the time, the issue happened

Jun 13 21:34:38 t495 kernel: [19938.983314] [drm:amdgpu_dm_commit_planes 
[amdgpu]] *ERROR* Waiting for fences timed out!
Jun 13 21:34:43 t495 kernel: [19938.983287] [drm:amdgpu_dm_commit_planes 
[amdgpu]] *ERROR* Waiting for fences timed out!
Jun 13 21:34:43 t495 kernel: [19943.851317] [drm:amdgpu_job_timedout 
[amdgpu]] *ERROR* ring sdma0 timeout, signaled seq=1122011, emitted 
seq=1122012
Jun 13 21:34:43 t495 kernel: [19943.851476] [drm:amdgpu_job_timedout 
[amdgpu]] *ERROR* Process information: process  pid 0 thread  pid 0
Jun 13 21:34:43 t495 kernel: [19943.851612] amdgpu 0000:06:00.0: amdgpu: 
GPU reset begin!

Doing some research on the web I found that there is supposed to be an 
option to enable/disable OpenCL in the preferences. But in my version I 
cannot find this under Preferences>System Resources.

So how can I tell if OpenCL is used and if so, how can I disable it, so 
that I can check whether this issue happening is really related to GIMP?

Thank you in advance
Stefan