text: // Cannot implicitly shard accessed collections because of extra shard key index in sharded
  // collection.
  // @tags: [assumes_no_implicit_index_creation]
  
  t = db.bench_test1;
  t.drop();
  
  t.insert({_id: 1, x: 1});
  t.insert({_id: 2, x: 1});
  
  ops = [
      {op: "findOne", ns: t.getFullName(), query: {_id: 1}},
      {op: "update", ns: t.getFullName(), query: {_id: 1}, update: {$inc: {x: 1}}}
  ];
  
  seconds = 10;
  
  benchArgs = {
      ops: ops,
      parallel: 2,
      seconds: seconds,
      host: db.getMongo().host
  };
  
  if (jsTest.options().auth) {
      benchArgs['db'] = 'admin';
      benchArgs['username'] = jsTest.options().authUser;
      benchArgs['password'] = jsTest.options().authPassword;
  }
  res = benchRun(benchArgs);
  
  assert.lte(seconds * res.update, t.findOne({_id: 1}).x * 1.5, "A1");
  
  assert.eq(1, t.getIndexes().length, "B1");
  benchArgs['ops'] = [{op: "createIndex", ns: t.getFullName(), key: {x: 1}}];
  benchArgs['parallel'] = 1;
  benchRun(benchArgs);
  assert.eq(2, t.getIndexes().length, "B2");
  benchArgs['ops'] = [{op: "dropIndex", ns: t.getFullName(), key: {x: 1}}];
  benchRun(benchArgs);
  assert.soon(function() {
      return t.getIndexes().length == 1;
  });
  