SOL > Devices > X86 CPUs

X86 CPUs

When using SOL on X86 CPUs we strongly recommend to set the following OMP env var.

export OMP_PROC_BIND=TRUE

Env Vars

EnvVar	Default	Description
CC	“gcc”	Path to gcc
CXX	“gcc”	Path to g++
COBJCOPY	“objcopy”	Path to objcopy
CAR	“ar”	Path to ar
CPATH		Used as include paths
C_INCLUDE_PATH		Used as include paths
CPLUS_INCLUDE_PATH		Used as include paths
LIBRARY_PATH		Used as library paths

Further see OpenMP Environment Variables.

FAQ

SOL performance using X86 is really really bad, what can I do?

SOL performance using X86 is really really bad, what can I do?
tl;dr; run once: `python3 -m sol fix-omp –yes` Unfortunately some python packages (e.g., torch or sklearn) ship their own version of `libgomp.so`. This causes that the application uses multiple OpenMP runtimes, which can cause a series of problems. If you don’t define `OMP_NUM_THREADS`, then only the very first loaded OpenMP runtime runs multi-threaded. Even worse, if you define `OMP_NUM_THREADS`, all runtimes run in parallel, but use different threadpools, so whenever you switch from one to the other, you will have significant overhead due to swapping the threads. The `python3 -m sol fix-omp –yes` command detects conflicting versions of `libgomp.so` and replaces them with a symlink to the system’s own version of `libgomp.so`, so that all libraries use the same threadpool. If you need to run this fixing within your script, because you are using a fully automated process, then you can use: `import sol.bugfixes sol.bugfixes.fix_omp()`

tl;dr; run once: python3 -m sol fix-omp –yes

Unfortunately some python packages (e.g., torch or sklearn) ship their own version of libgomp.so. This causes that the application uses multiple OpenMP runtimes, which can cause a series of problems. If you don’t define OMP_NUM_THREADS, then only the very first loaded OpenMP runtime runs multi-threaded. Even worse, if you define OMP_NUM_THREADS, all runtimes run in parallel, but use different threadpools, so whenever you switch from one to the other, you will have significant overhead due to swapping the threads. The python3 -m sol fix-omp –yes command detects conflicting versions of libgomp.so and replaces them with a symlink to the system’s own version of libgomp.so, so that all libraries use the same threadpool.

If you need to run this fixing within your script, because you are using a fully automated process, then you can use:

import sol.bugfixes
sol.bugfixes.fix_omp()