How to improve the performance of c# program -

i trying to extract sdf file geodatabase.as new sdf file created ,the memory usage program increases.to overcome issue have tried reaseing connection sdf file , tried release resources using gc.collect() method still problem persist.

/// <summary> /// feature data geodatabase file /// </summary> /// <param name="dictionaryproperty"> schema of table </param> /// <param name="table">table connection of gdb file</param> /// <param name="sdffilepath">sdf file path</param> static void getfeaturedata(dictionary<string, property> dictionaryproperty, table table, string sdffilepath) {     int filecount = 1; ;     list<property> propertylist = new list<property>();     ienumerable<string> propertycoll = dictionaryproperty.select(i => i.value).where(i => i.datatype == "oid").tolist().select(i => i.propertyname);     string propertyname = null;     foreach (string item in propertycoll)     {         propertyname = item;     }     (int rowno = 1; rowno <= table.rowcount; rowno++)     {         foreach (row row in table.search("*", propertyname + "=" + rowno.tostring(), rowinstance.recycle))         {             foreach (property property in dictionaryproperty.values)             {                 property objproperty = new property();                 objproperty.propertyname = property.propertyname;                 objproperty.datatype = property.datatype;                 switch (property.datatype)                 {                     case "smallinteger":                         if (row.isnull(property.propertyname))                         {                             objproperty.propertydata = "";                         }                         else                         {                             objproperty.propertydata = row.getshort(property.propertyname).tostring();                         }                         break;                      case "geometry":                         switch (row.getgeometry().geometrytype.tostring())                         {                             case "point":                                 pointshapebuffer pointgeometry = row.getgeometry();                                 objproperty.geometrytype = property.geometrytype;                                 objproperty.geometrydata = pointgeometry.point.x + " " + pointgeometry.point.y;                                 break;                                  objproperty.geometrydata = coord;                                 objproperty.propertydata = coord;                                 objproperty.geometrytype =   property.geometrytype;                                 coord = string.empty;                                 break;                             case "polygon":                                  break;                         }                         break;                     case "globalid":                          break;                 }                 propertylist.add(objproperty);             }             insertfeaturedata(table, propertylist, sdffilepath);             propertylist.clear();         }     }     console.writeline(filecount + "file completed");     filecount++; } /// <summary> /// insert feature data sdf file path /// </summary> /// <param name="table"></param> /// <param name="propertylist">schema defination</param> /// <param name="sdffilepath"></param> static void insertfeaturedata(table table, list<property> propertylist, string sdffilepath) {     iconnection con = openfdosdfconnection(sdffilepath);     iinsert insertcommand = (iinsert)con.createcommand(osgeo.fdo.commands.commandtype.commandtype_insert);     insertcommand.setfeatureclassname(gettablename(table));     foreach (property objproperty in propertylist)     {         switch (objproperty.datatype)         {             case "oid":                 if (!string.isnullorempty(objproperty.propertydata))                 {                     insertcommand.propertyvalues.add(new propertyvalue(objproperty.propertyname, new int64value(convert.toint64(objproperty.propertydata))));                 }                 else                 {                     insertcommand.propertyvalues.add(new propertyvalue(objproperty.propertyname, null));                 }                 break;              case "geometry":                 switch (objproperty.geometrytype)                 {                     case "point":                         if (!(objproperty.geometrydata == ""))                         {                             fgfgeometryfactory factory = new fgfgeometryfactory();                             directpositioncollection pcollection = new directpositioncollection();                             string[] points = objproperty.geometrydata.split();                             insertcommand.propertyvalues.add(new propertyvalue("geometry", new geometryvalue(factory.getfgf(factory.createpoint(factory.createpositionxy(convert.todouble(points[0]), convert.todouble(points[1])))))));                         }            }     }     insertcommand.execute();     insertcommand.dispose();     con.close(); }