18MB/s sounds rather low. It obviously rather depends on the source of data, format of data (e.g. lots of floating point columns is slower than large fields of

18MB/s sounds rather low. It obviously rather depends on the source of data, format of data (e.g. lots of floating point columns is slower than large fields of text), and whether parallelism is used. But you can relatively easily get around 300MB/s into an unindexed table, provided you have a rather decent storage system.