Butter the springform pans.
Preheat oven to 325 degrees F. Butter sided and bottom of three 4" springform pan.
Mix bread crumbs, 3 Tablespoons gruyere, and 1 teaspoon minced dill and coat the buttered springform pans. Refrigerate.
Melt butter in skillet over low heat. Add shallots, and cover and cook until translucent (about 5 minutes), stirring occasionally.
Mix cream cheese in food processor until smooth, add eggs, cheese, 1/2 & 1/2, dill and salt. Pulse until mixed. Add salmon and shallots and pulse again. Filling should retain some texture.
Pour into prepared pan. Set pan in roasting pan. Add enough hot water to roasting pan to come half way up sides of springform pan. Bake 1 hour at 325 degrees F.
Turn off oven and cool cheesecake in oven with the door ajar for another hour. Transfer to rack and cool to room temperature. Refrigerate for up to two days. Bring to room temperature before serving.