test_vm.py 文件源码

def test_speed_lazy():

    def build_graph(x, depth=5):
        z = x
        for d in range(depth):
            z = ifelse(z[0] > 0, -z, z)
        return z

    def time_linker(name, linker):
        steps_a = 10
        steps_b = 100
        x = tensor.vector()
        a = build_graph(x, steps_a)
        b = build_graph(x, steps_b)

        f_a = function([x], a,
                       mode=Mode(optimizer=None,
                                 linker=linker()))
        f_b = function([x], b,
                       mode=Mode(optimizer=None,
                                 linker=linker()))

        f_a([2.0])
        t0 = time.time()
        f_a([2.0])
        t1 = time.time()

        f_b([2.0])

        t2 = time.time()
        f_b([2.0])
        t3 = time.time()

        t_a = t1 - t0
        t_b = t3 - t2

        print("%s takes %f s/Kop" % (
            name,
            (1000 * (t_b - t_a) / (steps_b - steps_a))))

    time_linker('vmLinker', vm.VM_Linker)
    time_linker('vmLinker_nogc', lambda: vm.VM_Linker(allow_gc=False))
    if theano.config.cxx:
        time_linker('vmLinker_C', lambda: vm.VM_Linker(allow_gc=False,
                                                       use_cloop=True))