A couple thoughts: The number of cores in the machine is irrelevant, for the highest insert speed you need to be using a single thread/core for that. If you are not doing so then try to have a single inserter thread. I am not sure about your transaction size, but you should be able to achieve much higher throughput with larger transactions on modern hardware. Have you tried WAL with synchronous=0? This option leads to better insert speeds in some cases.