nproc
nproc prints the number of processor cores available.
nproc [options]
$ nproc
8
By default it prints the number of cores available to the current process — which can be fewer than the machine has, if the process has been restricted to a subset. It is most often used to decide how many parallel jobs to run.
Options #
| Option | Effect |
|---|---|
--all | Print the number of cores the whole system has, ignoring any restriction on the current process. |
--ignore=N | Subtract N from the count — for leaving some cores free rather than using every one. |
The environment variables OMP_NUM_THREADS and OMP_THREAD_LIMIT, if set, also bound the number nproc reports.
Exit status #
| Code | Meaning |
|---|---|
0 | The count was printed. |
1 | An option value was invalid. |