What is Linux Nproc?

What is Linux Nproc?

The maximum user processes (nproc) limit on Linux counts the number of threads within all processes that can exist for a given user. The default value of nproc is 1024 on some versions of Linux, which is generally an insufficient number of threads for all processes.

How many threads do I have Linux?

You will find how many threads you can run on your machine by running htop or ps command that returns number of process on your machine. You can use man page about ‘ps’ command. If you want to calculate number of all users process, you can use one of these commands: ps -aux| wc -l.

How do I know how many cores I have in Linux?

You can use one of the following command to find the number of physical CPU cores including all cores on Linux:

1. lscpu command.
2. cat /proc/cpuinfo.
3. top or htop command.
4. nproc command.
5. hwinfo command.
6. dmidecode -t processor command.
7. getconf _NPROCESSORS_ONLN command.

How many threads can I create?

Each processor has 10 cores, each core being basically equivalent to a classic single-core CPU on its own. Each core can only run 1 thread at a time, i.e. hyperthreading is disabled. So, you can have a total maximum of 20 threads executing in parallel, one thread per CPU/core.

How do I set Nproc limit?

Setting nproc hard/soft limits permanently – To set the nproc limit to unlimited system wide, the file /etc/security/limits. d/90-nproc. conf (RHEL5, RHEL6), /etc/security/limits. d/20-nproc.

Is there a command line option for nproc?

There exists a command line option –ignore which you can use to tell nproc that if possible, exclude a set number of processing units. PS: In case you want to know more about the nproc command, you can use the –help and –version options.

What’s the total number of processing units in nproc?

Instead of the number of available processing units, if you want nproc to display the total installed processing units, you can use the –all option. So on my system, the total number of installed processing units is 4.

Which is the best make-J$ ( nproc ) to use?

make -j$ (nproc) is a decent place to start, but you can usually use higher values, as long as you don’t exhaust your available memory and start thrashing. For really fast builds, if you have enough memory, I recommend using a tmpfs, that way most jobs will be CPU-bound and make -j$ (nproc) will work as fast as possible.