--nssize parameter

3 files changed, 33 insertions, 8 deletions

diff --git a/db/db.cpp b/db/db.cpp
index 3fdfdbb2625..efad0d2e41b 100644
--- a/db/db.cpp
+++ b/db/db.cpp
@@ -61,6 +61,7 @@ namespace mongo {
     extern int opLogging;
     extern long long oplogSize;
     extern OpLog _oplog;
+	extern int lenForNewNsFiles;
 
     extern int ctr;
     extern int callDepth;
@@ -483,6 +484,7 @@ int main(int argc, char* argv[], char *envp[] )
         ("nohttpinterface", "disable http interface")
         ("noscripting", "disable scripting engine")
         ("noprealloc", "disable data file preallocation")
+        ("nssize", po::value<int>()->default_value(16), ".ns file size (in MB) for new databases")
         ("oplog", po::value<int>(), "0=off 1=W 2=R 3=both 7=W+some reads")
         ("sysinfo", "print some diagnostic system information")
 #if defined(_WIN32)
@@ -693,6 +695,12 @@ int main(int argc, char* argv[], char *envp[] )
         if (params.count("autoresync")) {
             autoresync = true;
         }
+		if( params.count("nssize") ) { 
+            int x = params["nssize"].as<int>();
+            uassert("bad --nssize arg", x > 0 && x <= (0x7fffffff/1024/1024));
+			lenForNewNsFiles = x * 1024 * 1024;
+            assert(lenForNewNsFiles > 0);
+		}
         if (params.count("oplogSize")) {
             long x = params["oplogSize"].as<long>();
             uassert("bad --oplogSize arg", x > 0);
diff --git a/db/namespace.cpp b/db/namespace.cpp
index b34e379f7b7..3e5cc497901 100644
--- a/db/namespace.cpp
+++ b/db/namespace.cpp
@@ -42,12 +42,14 @@ namespace mongo {
     };
 
     bool NamespaceIndex::exists() const {
-        return !boost::filesystem::exists(path());        
+        return !boost::filesystem::exists(path());
     }
     
     boost::filesystem::path NamespaceIndex::path() const {
         return boost::filesystem::path( dir_ ) / ( database_ + ".ns" );
     }
+
+	int lenForNewNsFiles = 16 * 1024 * 1024;
     
     void NamespaceIndex::init() {
         if ( ht )
@@ -61,14 +63,29 @@ namespace mongo {
             i.dbDropped();
         }
 
-        long LEN = 16 * 1024 * 1024;
-        string pathString = path().string();
-        void *p = f.map(pathString.c_str(), LEN);
+		int len = -1;
+        boost::filesystem::path nsPath = path();
+        string pathString = nsPath.string();
+		void *p;
+        if( boost::filesystem::exists(nsPath) ) { 
+			p = f.map(pathString.c_str());
+			len = f.length();
+			uassert( "bad .ns file length, cannot open database", len % (1024*1024) == 0 );
+		}
+		else {
+			// use lenForNewNsFiles, we are making a new database
+			massert( "bad lenForNewNsFiles", lenForNewNsFiles >= 1024*1024 );
+			long l = lenForNewNsFiles;
+			p = f.map(pathString.c_str(), l);
+			len = (int) l;
+			assert( len == lenForNewNsFiles );
+		}
+
         if ( p == 0 ) {
             problem() << "couldn't open file " << pathString << " terminating" << endl;
             dbexit( EXIT_FS );
         }
-        ht = new HashTable<Namespace,NamespaceDetails>(p, LEN, "namespace index");
+        ht = new HashTable<Namespace,NamespaceDetails>(p, len, "namespace index");
     }
 
     void NamespaceDetails::addDeletedRec(DeletedRecord *d, DiskLoc dloc) {
diff --git a/db/namespace.h b/db/namespace.h
index 4470aa63f09..2ae5e3f0fc3 100644
--- a/db/namespace.h
+++ b/db/namespace.h
@@ -33,7 +33,7 @@ namespace mongo {
 
 	/* in the mongo source code, "client" means "database". */
 
-    const int MaxClientLen = 256; // max str len for the db name
+    const int MaxClientLen = 256; // max str len for the db name, including null char
 
 	// "database.a.b.c" -> "database"
     inline void nsToClient(const char *ns, char *database) {
@@ -554,10 +554,10 @@ namespace mongo {
             }
             return false;
         }
-        
+
         bool allocated() const {
             return ht != 0;
-        }   
+        }
 
     private:
         boost::filesystem::path path() const;