各位高手：

我用的是stata12，计算机是i7处理器，8g内存，windows64位系统，跑数据的时候为什么还会出现以下问题呢？
op. sys. refuses to provide memory
    Stata's data-storage memory manager has already allocated 1536m bytes and it just attempted to allocate another 16m bytes.  The  operating system said no.  Perhaps you are running another memory-consuming task and the command will work later when the task  completes.  Perhaps you are on a multiuser system that is especially busy and the command will work later when activity quiets down.   Perhaps a system administrator has put a limit on what you can allocate; see help memory.  Or perhaps that's all the memory your computer can allocate to Stata.
r(909);
memory重新set也不行。。这是怎么回事?很急！谢谢大家了！这个数据库也不大，几十万条数据。