  We use gauge/gravity correspondence to study the gravitational reheating of
strongly coupled gauge theories in the rapid exit from the long inflationary
(de Sitter) phase. We estimate the maximal reheating temperature of holographic
models in $d$-spatial dimensions, which scale invariance is explicitly broken
by a source term for an operator ${\cal O}_\Delta$ of dimension $\frac d2+\frac
12< \Delta< d+1$, as well as the top-down ${\cal N}=2^*$ and the cascading
gauge theories. The reheating is most efficient when the inflationary phase
Hubble constant is much larger than the mass scale of the conformal symmetry
breaking of the theory, and for theories with the conformal symmetry breaking
operators that are close to marginal.
