详解C调用lua脚本效率测试

C调用lua脚本效率测试是本文要介绍的内容，以下代码以C语言为基准，测试了C调用Lua循环和循环调用Lua的效率。结论是不要频繁地穿越C/Lua边界.

1. #include <time.h>
2. extern "C"
3. {
4. #include "lua.h"
5. #include "lualib.h"
6. #include "lauxlib.h"
7. }/* Lua解释器指针 */
8. const char LUA_SCRIPT[] =
9. "function loop_add(a, b) "
10. " local sum = 0 "
11. " for i = 1, 10000000 do "
12. " sumsum = sum + a + b "
13. " end "
14. " return sum "
15. "end "
16. " "
17. "function add(a, b) "
18. " return a + b "
19. "end "
20. ;
21. // lua 脚本里面的函数由C调用
22. int use_lua_add(lua_State *L, const char *func_name, int x, int y)
23. {
24. int sum; /* 通过名字得到Lua函数 */
25. lua_getglobal(L, func_name); /* 第一个参数 */
26. lua_pushnumber(L, x); /* 第二个参数 */
27. lua_pushnumber(L, y); /* 调用函数，告知有两个参数，一个返回值 */
28. lua_call(L, 2, 1); /* 得到结果 */
29. sum = (int)lua_tointeger(L, -1);
30. lua_pop(L, 1);
31. return sum;
32. }
33. int main()
34. {
35. int i, sum = 0;
36. clock_t tStart, tStop;
37. lua_State *L = lua_open(); /* opens Lua */
38. luaL_openlibs(L);
39. if (luaL_dostring(L, LUA_SCRIPT)) // Run lua script
40. {
41. printf("run script failed/n");
42. lua_close(L);
43. return -1;
44. }
45. sum = 0;
46. tStart = clock();
47. for (i = 0; i <10000000; i++)
48. {
49. sum += 1 + 1;
50. }
51. tStop = clock();
52. printf("C++: %dms./nThe sum is %u./n",
53. (tStop - tStart) * 1000 / CLOCKS_PER_SEC, sum);
54. sum = 0;
55. tStart = clock();
56. sum = use_lua_add(L, "loop_add", 1, 1);
57. tStop = clock();
58. printf("Lua loop_add: %dms./nThe sum is %u./n",
59. (tStop - tStart) * 1000 / CLOCKS_PER_SEC, sum);
60. sum = 0;
61. tStart = clock();
62. for (i = 0; i <10000000; i++)
63. {
64. sum += use_lua_add(L, "add", 1, 1);
65. }
66. tStop = clock();
67. printf("Loop lua add: %dms./nThe sum is %u./n",
68. (tStop - tStart) * 1000 / CLOCKS_PER_SEC, sum);
69. lua_close(L);
70. return 0;
71. }

运行结果：

1. C++: 31ms.
2. The sum is 20000000.
3. Lua loop_add: 437ms.
4. The sum is 20000000.
5. Loop lua add: 2360ms.
6. The sum is 20000000.

小结：详解C调用lua脚本效率测试的内容介绍完了，希望通过本文的学习能对你有所帮助！

想看看c调用lua和lua调用c效率有多大差别吗？

加一种测试：

"function loop_cadd(a, b) "

" local sum = 0 "

" for i = 1, 10000000 do "

" sum = sum + csum(a,b) "

" end "

" return sum "

"end "

其中csum是一个c函数

int csum(lua_State* l)

{

int a = lua_tointeger(l,1) ;

int b = lua_tointeger(l,2) ;

lua_pushinteger(l,a+b) ;

return 1 ;

}

测试结果如下：

C++: 21ms.

The sum is 20000000.

Lua loop_add: 640ms.

The sum is 20000000.

Lua loop_cadd: 3027ms.

The sum is 20000000.

Loop lua add: 3927ms.

The sum is 20000000.

结论是从lua调用c函数要比c调用lua函数快一点点。