put hotter things adjacent for cache friendliness

4 files changed, 19 insertions, 10 deletions

diff --git a/db/common.cpp b/db/common.cpp
index b7883f5e425..e711df9bfdc 100644
--- a/db/common.cpp
+++ b/db/common.cpp
@@ -26,4 +26,15 @@ namespace mongo {
     /* we use new here so we don't have to worry about destructor orders at program shutdown */
     MongoMutex &dbMutex( *(new MongoMutex("rw:dbMutex")) );
 
+    MongoMutex::MongoMutex(const char *name) : _m(name) {
+        static int n;
+        assert( ++n == 1 ); // singleton class
+
+        /*cout << sizeof(*this) << endl;
+        cout << sizeof(MutexInfo) << endl;
+        cout << sizeof(RWLock) << endl;
+        cout << sizeof(ThreadLocalValue<int>) << endl;
+        _state.get();*/
+    }
+
 }
diff --git a/db/concurrency.h b/db/concurrency.h
index c74fd7d01e2..b0f2c508fb3 100644
--- a/db/concurrency.h
+++ b/db/concurrency.h
@@ -43,8 +43,9 @@ namespace mongo {
 
     /* mutex time stats */
     class MutexInfo {
-        unsigned long long start, enter, timeLocked; // all in microseconds
+        unsigned long long enter, timeLocked; // microseconds
         int locked;
+        unsigned long long start; // last as we touch this least often
 
     public:
         MutexInfo() : timeLocked(0) , locked(0) {
@@ -62,16 +63,12 @@ namespace mongo {
             if ( locked == 0 )
                 timeLocked += curTimeMicros64() - enter;
         }
-        int isLocked() const {
-            return locked;
-        }
+        int isLocked() const { return locked; }
         void getTimingInfo(unsigned long long &s, unsigned long long &tl) const {
             s = start;
             tl = timeLocked;
         }
-        unsigned long long getTimeLocked() const {
-            return timeLocked;
-        }
+        unsigned long long getTimeLocked() const { return timeLocked; }
     };
 
 }
diff --git a/db/mongomutex.h b/db/mongomutex.h
index ca8fd128c61..f2493909ca7 100644
--- a/db/mongomutex.h
+++ b/db/mongomutex.h
@@ -22,7 +22,7 @@ namespace mongo {
 
     class MongoMutex {
     public:
-        MongoMutex(const char * name) : _m(name) { }
+        MongoMutex(const char * name);
 
         /** @return
          *    > 0  write lock
@@ -172,7 +172,6 @@ namespace mongo {
         MutexInfo& info() { return _minfo; }
 
     private:
-        MutexInfo _minfo;
         RWLock _m;
 
         /* > 0 write lock with recurse count
@@ -180,6 +179,8 @@ namespace mongo {
         */
         ThreadLocalValue<int> _state;
 
+        MutexInfo _minfo;
+
         /* See the releaseEarly() method.
            we use a separate TLS value for releasedEarly - that is ok as 
            our normal/common code path, we never even touch it */
diff --git a/util/goodies.h b/util/goodies.h
index 0f995aec5f2..aeffd14b976 100644
--- a/util/goodies.h
+++ b/util/goodies.h
@@ -218,8 +218,8 @@ namespace mongo {
         }
 
     private:
-        const T _default;
         boost::thread_specific_ptr<T> _val;
+        const T _default;
     };
 
     class ProgressMeter : boost::noncopyable {