collectgarbage()

collectgarbage ([opt [, arg]])

This function is a generic interface to the garbage collector. It performs different functions according to its first argument, opt:

• "collect": performs a full garbage-collection cycle. This is the default option.
• "stop": stops automatic execution of the garbage collector. The collector will run only when explicitly invoked, until a call to restart it.
• "restart": restarts automatic execution of the garbage collector.
• "count": 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 (except for overflows).
• "step": performs a garbage-collection step. The step "size" is controlled by arg. With a zero value, the collector will perform one basic (indivisible) step. For non-zero values, the collector will perform as if that amount of memory (in KBytes) had been allocated by Lua. Returns true if the step finished a collection cycle.
• "setpause": sets arg as the new value for the pause of the collector (see §2.5). Returns the previous value for pause.
• "setstepmul": sets arg as the new value for the step multiplier of the collector (see §2.5). Returns the previous value for step.
• "isrunning": returns a boolean that tells whether the collector is running (i.e., not stopped).