Autoselection of OpenGL backend may file with X forwarding
Created by: grisuthedragon
On RHEL7/CentOS7 the GLdispatch approach is used by default. This leads on my system to a strange situation using ssh X11 forwarding.
Server: CentOS 7, 2x K20 cards, CUDA 10.1, no running X
Client: Ubuntu 16.04, X with nouveau driver.
If the OpenGL libs are installed on the server, i.e. the package nvidia-driver-latest-dkms-libs-418.87.00-2.el7.x86_64 is installed, and I run glxinfo I get:
$ glxinfo
name of display: localhost:11.0
X Error of failed request: BadValue (integer parameter out of range for operation)
Major opcode of failed request: 155 (GLX)
Minor opcode of failed request: 24 (X_GLXCreateNewContext)
Value in failed request: 0x0
Serial number of failed request: 39
Current serial number in output stream: 40
If the package is not installed or the libraries matching '/usr/lib64/lin[EG]nvidia' are moved somewhere, the GL implementation from mesa is used and everything works:
$ glxinfo
name of display: localhost:11.0
display: localhost:11 screen: 0
direct rendering: Yes
server glx vendor string: SGI
server glx version string: 1.4
server glx extensions:
GLX_ARB_create_context, GLX_ARB_create_context_profile,
GLX_ARB_fbconfig_float, GLX_ARB_framebuffer_sRGB, GLX_ARB_multisample,
GLX_EXT_create_context_es2_profile, GLX_EXT_create_context_es_profile,
GLX_EXT_fbconfig_packed_float, GLX_EXT_framebuffer_sRGB,
GLX_EXT_import_context, GLX_EXT_texture_from_pixmap, GLX_EXT_visual_info,
GLX_EXT_visual_rating, GLX_INTEL_swap_event, GLX_MESA_copy_sub_buffer,
GLX_OML_swap_method, GLX_SGIS_multisample, GLX_SGIX_fbconfig,
GLX_SGIX_pbuffer, GLX_SGIX_visual_select_group, GLX_SGI_swap_control
client glx vendor string: Mesa Project and SGI
client glx version string: 1.4
client glx extensions:
GLX_ARB_context_flush_control, GLX_ARB_create_context,
GLX_ARB_create_context_profile, GLX_ARB_create_context_robustness,
GLX_ARB_fbconfig_float, GLX_ARB_framebuffer_sRGB,
GLX_ARB_get_proc_address, GLX_ARB_multisample, GLX_EXT_buffer_age,
GLX_EXT_create_context_es2_profile, GLX_EXT_create_context_es_profile,
GLX_EXT_fbconfig_packed_float, GLX_EXT_framebuffer_sRGB,
GLX_EXT_import_context, GLX_EXT_texture_from_pixmap, GLX_EXT_visual_info,
GLX_EXT_visual_rating, GLX_INTEL_swap_event, GLX_MESA_copy_sub_buffer,
GLX_MESA_multithread_makecurrent, GLX_MESA_query_renderer,
GLX_MESA_swap_control, GLX_OML_swap_method, GLX_OML_sync_control,
GLX_SGIS_multisample, GLX_SGIX_fbconfig, GLX_SGIX_pbuffer,
GLX_SGIX_visual_select_group, GLX_SGI_make_current_read,
GLX_SGI_swap_control, GLX_SGI_video_sync
GLX version: 1.4
GLX extensions:
GLX_ARB_create_context, GLX_ARB_create_context_profile,
GLX_ARB_fbconfig_float, GLX_ARB_framebuffer_sRGB,
...
and everything works.
Is there a way to bypass the autodetection of GLDispatch? or if not it should be, e.g. in terms of an enviroment variable like
export GLDISPATCH_USE=mesa/nvidia/...
Otherwise I get introuble even with easy OpenGL applications like the QT based function plotter in octave.