Tom Kraljevic
2014-Aug-05 02:49 UTC
[Rd] R process (and forked children via system2) are limited to 1 core?
Hi, (Using R 3.1.1 on Ubuntu 12.04.4 LTS) What is the recommended way for R to fork a (non-R) process that is not CPU limited? Currently I am using R?s system2() call, and this is inheriting the environment of the R process. I notice that (at least on Linux) when I am poking around /proc that the R process itself is setting up cpu limitations for itself (max 1 core). Using strace, I see the following: (strace output) out.20612:sched_setaffinity(0, 128, {100, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}) = 0 And proc shows: (cat /proc/nnn/status) Cpus_allowed: 00000001 Cpus_allowed_list: 0 See that the Cpus_allowed bitmask is a single core. Normally it?s fff?f. I want my child process (java in this case) not to share this limitation. What is the recommended way of doing this from R? Any ideas or suggestions appreciated! Thanks, Tom