1.Generally speaking, a suction pump is installed on the ground floor of a house to draw tap water from the first floor or water from an underground reservoir and send it to the rooftop. A booster pump, on the other hand, is installed on the rooftop to send water from the rooftop water tank to taps in the house. Both are collectively known as water pumps.
2.How frequently a suction pump starts to operate depends on how much water is used in a household. However, you can choose to increase the amount of water stored in your water tank by adjusting its level switch, lowering the low point level (to no lower than the inlet of the booster pump), and raising the high point level (to no higher than then float valve fitted to the inlet pipe). Then the pump on the ground floor won't be activated so often.
Note: Remember to check if there is a water leak in your home or if your water bill is unusually high.