Spawners?

I found 4 spider spawners all right next to each other in survival and was working on making a farm, it’s quite nice.

My question is does having more than one active at a time actually increase spawn speed or will the same amount of spiders spawn just distributed across all four?

Cause I don’t want to kill efficiency of my farm and I could split spawners in 4 different farms if that would spawn more mobs, just need that loot.