CODEWITHSUNDEEP
crystal-lang
Sam Eaton
Sam Eaton

Reputation: 1835

How to detect number of CPU cores in Crystal?

How do you detect the number of CPU cores in crystal?

In Go you can do runtime.NumCPU() and in Node.js you can do os.cpus(). Is there something similar in Crystal?

Upvotes: 1

Views: 401

Answers (2)

taylorthurlow
taylorthurlow

Reputation: 3073

Use System.cpu_count. This will give you the number of logical cores available. This method was introduced in Crystal 0.23.0.

Here's the source for it in the tree for Crystal 0.29.0: https://github.com/crystal-lang/crystal/blob/fbfe8b62f44eca4596090b7580801bd184f73c7a/src/system.cr#L22

Upvotes: 0

Oleh Prypin
Oleh Prypin

Reputation: 34116

The last time I checked (admittedly that was long ago) there was no direct way to do that, but you can get access to this information through the command line. I ended up combining multiple of these answers for redundancy.

THREADS = `getconf _NPROCESSORS_ONLN || nproc --all || grep -c '^processor' /proc/cpuinfo`.to_i

Upvotes: 2

Related Questions