用stata 12.0运行exact logistic 回归，样本量300+（其中阳性结局数量70+），自变量20个

报错内容如下：
exceeded memory limit of 10.0M bytes; use the memory() option to
increase the memory limit
r(499);

但是，set memory 400m后，也报错，如下：
set memory ignored.
    Memory no longer needs to be set in modern Statas; memory adjustments are
    performed on the fly automatically.

请问各位大牛，这种情况怎么解决啊？谢谢！