What limits the number of secondary guns on a warship?

How many secondary weapons of 76 mm and smaller become excessive once their radar and computing needs are considered?

Computing demand is manageable; ammunition, support capacity, and the ship's available deck and internal space set the more practical limits.

The preferred starting battery includes four 76 mm guns alongside four additional mounts whose system name is unclear in the captions. The main radar can provide general targeting information while individual weapons retain their own systems. Additional computing is described as a modest server requirement, with equipment repeated two or three times in separated racks so damage to one location need not disable the rest. Ammunition capacity, support requirements and usable deck space impose stronger limits. An empty patch of deck does not establish that a mounting can go there, because the spaces and structure beneath it also matter.