To submit to CRAN we cannot use more than 2 threads in our examples/vignettes

R-package/man/xgb.save.Rd

@@ -20,7 +20,7 @@ data(agaricus.test, package='xgboost')
 train <- agaricus.train
 test <- agaricus.test
 bst <- xgboost(data = train$data, label = train$label, max.depth = 2,
-               eta = 1, nround = 2,objective = "binary:logistic")
+               eta = 1, nthread = 2, nround = 2,objective = "binary:logistic")
 xgb.save(bst, 'xgb.model')
 bst <- xgb.load('xgb.model')
 pred <- predict(bst, test$data)