The branch, pu/nproc has been created at dcec9cf5bd2409f6ef61dd6443a9b4ecf01e64b2 (commit)
- Shortlog ------------------------------------------------------------ commit dcec9cf5bd2409f6ef61dd6443a9b4ecf01e64b2 Author: Sven Eckelmann sven@narfation.org Date: Wed Jun 23 14:12:58 2010 +0200
batmand: Use nproc to get number of available processors
The current way of getting the number of cpus uses different assumptions which may or may not be true in the future: * /proc/cpuinfo exists * cpuinfo provides a list of all processing units * all processing units are available for the current process and its childs * the word 'processor' is only used in the cpu index and 'model name' lines * cpu index is strict monotonic increasing * lowest cpu index is 0 and highest cpu index is n-1 (n is the number of processing units)
At least the number of available processing units for the current process can be shown to be wrong. on current systems by assigning a singe cpu to a process and its childs:
$ numactl --physcpubind=0 nproc 1
$ numactl --physcpubind=0 sh -c 'NUM_CPUS=`cat /proc/cpuinfo | grep -v "model name" | grep processor | tail -1 | awk -F" " '''{print $$3}'''`;echo `expr $NUM_CPUS + 1`' 4
nproc is part of coreutils since version 8.1. On systems without nproc it will just assume that a single processing unit is available.
Signed-off-by: Sven Eckelmann sven@narfation.org
-----------------------------------------------------------------------