Output Control
--------------
-``GMX_CONSTRAINTVIR``
- Print constraint virial and force virial energy terms.
-
``GMX_DUMP_NL``
Neighbour list dump level; default 0.
files. Set to 0 for quiet operation.
``GMX_ENABLE_GPU_TIMING``
- Enables GPU timings in the log file for CUDA. Note that CUDA timings
- are incorrect with multiple streams, as happens with domain
+ Enables GPU timings in the log file for CUDA and SYCL. Note that CUDA
+ timings are incorrect with multiple streams, as happens with domain
decomposition or with both non-bondeds and PME on the GPU (this is
also the main reason why they are not turned on by default).
(for coordinate and force buffers) directly on GPU memory spaces, without the staging of data through CPU
memory, where possible.
+``GMX_GPU_SYCL_NO_SYNCHRONIZE``
+ disable synchronizations between different GPU streams in SYCL build, instead relying on SYCL runtime to
+ do scheduling based on data dependencies. Experimental.
+
``GMX_CYCLE_ALL``
times all code during runs. Incompatible with threads.
``GMX_DISABLE_GPU_TIMING``
timing of asynchronously executed GPU operations can have a
non-negligible overhead with short step times. Disabling timing can improve performance in these cases.
+ Timings are disabled by default with CUDA and SYCL.
``GMX_DISABLE_GPU_DETECTION``
when set, disables GPU detection even if :ref:`gmx mdrun` was compiled
``GMX_OCL_DISABLE_FASTMATH``
Prevents the use of ``-cl-fast-relaxed-math`` compiler option.
+ Not: fast math is always disabled on Intel devices due to instability.
``GMX_OCL_DUMP_LOG``
If defined, the OpenCL build log is always written to the
``GMX_OCL_NOGENCACHE``).
- NVIDIA GPUs: PTX code is saved in the current directory
- with the name ``device_name.ptx``
- - AMD GPUs: ``.IL/.ISA`` files will be created for each OpenCL
+ with the name ``device_name.ptx``
+ - AMD GPUs: ``.IL/.ISA`` files will be created for each OpenCL
kernel built. For details about where these files are
created check AMD documentation for ``-save-temps`` compiler
option.