Add cpu_limit to ninja link pool on windows.

pylib/gyp/generator/ninja.py

Index: pylib/gyp/generator/ninja.py
===================================================================
--- pylib/gyp/generator/ninja.py	(revision 1722)
+++ pylib/gyp/generator/ninja.py	(working copy)
@@ -1506,7 +1506,9 @@
     stat.dwLength = ctypes.sizeof(stat)
     ctypes.windll.kernel32.GlobalMemoryStatusEx(ctypes.byref(stat))
 
-    return max(1, stat.ullTotalPhys / (4 * (2 ** 30)))  # total / 4GB
+    mem_limit = max(1, stat.ullTotalPhys / (4 * (2 ** 30)))  # total / 4GB
+    cpu_limit = multiprocessing.cpu_count()

[scottmg, 2013/09/11 20:09:06]

that does

    if sys.platform == 'win32':
        try:
            num = int(os.environ['NUMBER_OF_PROCESSORS'])
        except (ValueError, KeyError):
            num = 0

so maybe clamp to >= 1 too?

+    return min(mem_limit, cpu_limit)
   elif sys.platform.startswith('linux'):
     with open("/proc/meminfo") as meminfo:
       memtotal_re = re.compile(r'^MemTotal:\s*(\d*)\s*kB')