At the Japan Proton Accelerator Research Complex, a pulsed spallation neutron source has been providing neutron beams with high intensities and narrow pulse widths since 2008 for various materials science experiments. The neuron-pulse characteristics measured during early low-power operations indicated that this source is capable of providing the world's highest peak neutron intensities and pulse resolution at the 1-MW operation level, which is the goal of the facility. To achieve this operational goal, efforts have been underway to solve a critical issue affecting the target operation, i.e. mitigation of cavitation damages at the front end of the mercury target vessel, by injecting gas micro-bubbles and using a fast flow of the mercury through a narrow channel. Another issue is that the target vessel needs to be redesigned to ensure its robustness against the cyclic thermal stress produced by the temperature swings when the proton-beam trips because the water shroud surrounding the mercury target vessel failed during 500-kW operation in 2015.