Updating mongodb with java driver takes forever? -

so case: have program takes 2 large csv-files, finds diffs , sends array list method supposed update mongodb lines array. problem updates taking forever. test case 5000 updates takes 36 minutes. normal?

the update(list<string> changes)-method this:

mongoclient = new mongoclient(ip); db = mongoclient.getdb("foo"); collection = db.getcollection("bar");  //for each line of change (string s : changes) {     //splits csv-lines on ;     string[] fields = s.split(";");      //identifies wich document in database updated     long id = long.parselong(fields[0]);     basicdbobject sq = new basicdbobject().append("organizationnumber",id);      //creates new unit-object, converted json , inserted database.     unit u = new unit(fields);     gson gson = new gson();     string jsonobj = gson.tojson(u);     dbobject objecttoupdate = collection.findone(sq);     dbobject newobject = (dbobject) json.parse(jsonobj);      if(objecttoupdate != null){         objecttoupdate.putall(newobject);         collection.save(objecttoupdate); } 

that's because taking steps update. don't need parse jsons manually , don't have query-then-update when can update "where" clause in single step.

something this:

basicdbobject query= new basicdbobject().append("organizationnumber",id); unit unit = new unit(fields); basicdbobject unitdb= new basicdbobject().append("somefield",unit.getsomefield()).append("otherfield",unit.getotherfield()); collection.update(query,unitdb); 

where query specifies "where" clause , unitdb specifies fields need updated.