lua 垃圾回收

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lua 垃圾回收

      

           

                               

垃圾回收

        

lua 自动进行垃圾收集，可不用手动操作

      

collectgarbage(opt, arg) ：垃圾收集，arg可选

This function is a generic interface to the garbage collector. It performs 
different functions according to its first argument, opt:
* 该函数用于垃圾收集，第一个参数可控制垃圾回收动作

# collect：做一次完整的垃圾收集循环，默认
Performs a full garbage-collection cycle. This is the default option.

# stop：停止垃圾收集器的运行，直到显示开启垃收集器
Stops automatic execution of the garbage collector. The collector 
will run only when explicitly invoked, until a call to restart it.

# restart：重新开启垃圾回收器，使其自动运行
Restarts automatic execution of the garbage collector.

# count：以K（kb）为单位返回 Lua 使用的总内存数
Returns the total memory in use by Lua in Kbytes. The value has a 
fractional part, so that it multiplied by 1024 gives the exact 
number of bytes in use by Lua.

# step：单步运行垃圾收集器，步长由arg控制
Performs a garbage-collection step. The step "size" is controlled by arg. 
With a zero value, the collector will perform one basic (indivisible) step