Merge pull request #549 from graaff/alpha-processor-count-support

Support Alpha architecture for processor_count

Author: jdantonio

CHANGELOG.md

@@ -1,3 +1,5 @@
+* Support Alpha with `Concurrent::processor_count`
+
 ## Current Release v1.0.2 (2 May 2016)
 
 * Fix bug with `Concurrent::Map` MRI backend `#inspect` method

lib/concurrent/utility/processor_counter.rb

@@ -28,6 +28,7 @@ def initialize
       # processor", which taked into account hyperthreading.
       #
       # * AIX: /usr/sbin/pmcycles (AIX 5+), /usr/sbin/lsdev
+      # * Alpha: /usr/bin/nproc (/proc/cpuinfo exists but cannot be used)
       # * BSD: /sbin/sysctl
       # * Cygwin: /proc/cpuinfo
       # * Darwin: /usr/bin/hwprefs, /usr/sbin/sysctl
@@ -84,6 +85,8 @@ def compute_processor_count
             result = WIN32OLE.connect("winmgmts://").ExecQuery(
               "select NumberOfLogicalProcessors from Win32_Processor")
             result.to_enum.collect(&:NumberOfLogicalProcessors).reduce(:+)
+          elsif File.executable?("/usr/bin/nproc")
+            IO.popen("/usr/bin/nproc --all").read.to_i
           elsif File.readable?("/proc/cpuinfo")
             IO.read("/proc/cpuinfo").scan(/^processor/).size
           elsif File.executable?("/usr/bin/hwprefs")