An airfoil includes a body that includes leading and trailing edges joined by spaced apart pressure and suction sides to provide an exterior airfoil surface. A cooling passage is arranged interiorly of the exterior airfoil surface and provides an interior surface. The interior cooling surface includes micro-bumps that protrude from the interior cooling surface into the cooling passage. The micro-bumps are discrete from and noncontiguous relative to one another in multiple directions along the interior cooling surface. The micro-bumps may be provided while forming the airfoil or using correspondingly shaped micro-depressions on an airfoil core.