Merge commit 'upstream/1.8.2'

1 files changed, 41 insertions, 1 deletions

diff --git a/util/version.cpp b/util/version.cpp
index f57e256..78a31be 100644
--- a/util/version.cpp
+++ b/util/version.cpp
@@ -23,10 +23,11 @@
 #include <string>
 #include "unittest.h"
 #include "version.h"
+#include "file.h"
 
 namespace mongo {
 
-    const char versionString[] = "1.8.1";
+    const char versionString[] = "1.8.2";
 
     string mongodVersion() {
         stringstream ss;
@@ -94,6 +95,45 @@ namespace mongo {
             cout << "** WARNING: You are running in OpenVZ. This is known to be broken!!!" << endl;
             warned = true;
         }
+
+        if (boost::filesystem::exists("/sys/devices/system/node/node1")){
+            // We are on a box with a NUMA enabled kernel and more than 1 numa node (they start at node0)
+            // Now we look at the first line of /proc/self/numa_maps
+            //
+            // Bad example:
+            // $ cat /proc/self/numa_maps
+            // 00400000 default file=/bin/cat mapped=6 N4=6
+            //
+            // Good example:
+            // $ numactl --interleave=all cat /proc/self/numa_maps
+            // 00400000 interleave:0-7 file=/bin/cat mapped=6 N4=6
+
+            File f;
+            f.open("/proc/self/numa_maps", /*read_only*/true);
+            if ( f.is_open() && ! f.bad() ) {
+                char line[100]; //we only need the first line
+                f.read(0, line, sizeof(line));
+                
+                // just in case...
+                line[98] = ' ';
+                line[99] = '\0';
+                
+                // skip over pointer
+                const char* space = strchr(line, ' ');
+                
+                if ( ! space ) {
+                    cout << "** WARNING: cannot parse numa_maps" << endl;
+                    warned = true;
+                }
+                else if ( ! startsWith(space+1, "interleave") ) {
+                    cout << endl;
+                    cout << "** WARNING: You are running on a NUMA machine." << endl;
+                    cout << "**          We suggest launching mongod like this to avoid performance problems:" << endl;
+                    cout << "**              numactl --interleave=all mongod [other options]" << endl;
+                    warned = true;
+                }
+            }
+        }
 #endif
 
         if (warned)