普通变量与寄存器变量速度对比文档格式.docx

1、对于C程序，寄存器变量是不能取址的：几种线程本地存储变量和普通变量的性能比较God一直致力于研究高并发服务端的开发，这次要优化的是libGod库中的线程本地存储变量，线程本地存储变量访问非常频繁，优化后库的性能应该会提高不少。已知的线程本地存储方法有boost中的thread_specific_ptr类，gcc中的_thread关键字，pthread中的pthread_getspecific函数。这次测试这3中本地存储以及普通变量之间的性能差别，代码如下：#include iostream#include stdio.h#include pthread.h#include boost/thre

2、ad/thread.hpp#include boost/thread/tss.hppusing namespace std;class C public：C（int a） m_a = a;printf（“C（） %dn”， m_a）;C（） printf（“C（） %dn”， m_a）;private：int m_a;#define TM 3#if TM = 1boost：thread_specific_ptrC pc;const char *testType = “boost”;#elif TM = 2_thread C *pc;const char *testType = “_thread

3、”;#elif TM = 3pthread_key_t pc;const char *testType = “pthread”;#elseC *pc;const char *testType = “normal”;#endifvoid boostthreadFunc（） pc.reset（new C（10）;pc = new C（20）;if （pthread_key_create（cout “pthread_key_create” endl;return;if （pthread_setspecific（pc， new C（30） cout “pthread_setspecific” endl

4、;int switches = 5000000;int i = switches;struct timeval tm_start， tm_end;getTImeofday（while （i-） C *c1 = pc.get（）;C *c2 = pc.get（）;C *c3 = pc.get（）;C *c4 = pc.get（）;C *c5 = pc.get（）;C *c6 = pc.get（）;C *c7 = pc.get（）;C *c8 = pc.get（）;C *c9 = pc.get（）;C *c10 = pc.get（）;C *c11 = pc.get（）;C *c12 = pc.ge

5、t（）;C *c13 = pc.get（）;C *c14 = pc.get（）;C *c15 = pc.get（）;C *c16 = pc.get（）;C *c17 = pc.get（）;C *c18 = pc.get（）;C *c19 = pc.get（）;C *c20 = pc.get（）;C *c21 = pc.get（）;C *c22 = pc.get（）;C *c23 = pc.get（）;C *c24 = pc.get（）;C *c25 = pc.get（）;C *c26 = pc.get（）;C *c27 = pc.get（）;C *c28 = pc.get（）;C *c29 =

6、 pc.get（）;C *c30 = pc.get（）;C *c31 = pc.get（）;C *c32 = pc.get（）;C *c33 = pc.get（）;C *c34 = pc.get（）;C *c35 = pc.get（）;C *c36 = pc.get（）;C *c37 = pc.get（）;C *c38 = pc.get（）;C *c39 = pc.get（）;C *c40 = pc.get（）;C *c1 = pc;C *c2 = pc;C *c3 = pc;C *c4 = pc;C *c5 = pc;C *c6 = pc;C *c7 = pc;C *c8 = pc;C *c

7、9 = pc;C *c10 = pc;C *c11 = pc;C *c12 = pc;C *c13 = pc;C *c14 = pc;C *c15 = pc;C *c16 = pc;C *c17 = pc;C *c18 = pc;C *c19 = pc;C *c20 = pc;C *c21 = pc;C *c22 = pc;C *c23 = pc;C *c24 = pc;C *c25 = pc;C *c26 = pc;C *c27 = pc;C *c28 = pc;C *c29 = pc;C *c30 = pc;C *c31 = pc;C *c32 = pc;C *c33 = pc;C *c3

8、4 = pc;C *c35 = pc;C *c36 = pc;C *c37 = pc;C *c38 = pc;C *c39 = pc;C *c40 = pc;C *c1 = （C *）pthread_getspecific（pc）;C *c2 = （C *）pthread_getspecific（pc）;C *c3 = （C *）pthread_getspecific（pc）;C *c4 = （C *）pthread_getspecific（pc）;C *c5 = （C *）pthread_getspecific（pc）;C *c6 = （C *）pthread_getspecific（pc）

9、;C *c7 = （C *）pthread_getspecific（pc）;C *c8 = （C *）pthread_getspecific（pc）;C *c9 = （C *）pthread_getspecific（pc）;C *c10 = （C *）pthread_getspecific（pc）;C *c11 = （C *）pthread_getspecific（pc）;C *c12 = （C *）pthread_getspecific（pc）;C *c13 = （C *）pthread_getspecific（pc）;C *c14 = （C *）pthread_getspecific（pc

10、）;C *c15 = （C *）pthread_getspecific（pc）;C *c16 = （C *）pthread_getspecific（pc）;C *c17 = （C *）pthread_getspecific（pc）;C *c18 = （C *）pthread_getspecific（pc）;C *c19 = （C *）pthread_getspecific（pc）;C *c20 = （C *）pthread_getspecific（pc）;C *c21 = （C *）pthread_getspecific（pc）;C *c22 = （C *）pthread_getspecifi

11、c（pc）;C *c23 = （C *）pthread_getspecific（pc）;C *c24 = （C *）pthread_getspecific（pc）;C *c25 = （C *）pthread_getspecific（pc）;C *c26 = （C *）pthread_getspecific（pc）;C *c27 = （C *）pthread_getspecific（pc）;C *c28 = （C *）pthread_getspecific（pc）;C *c29 = （C *）pthread_getspecific（pc）;C *c30 = （C *）pthread_getspe

12、cific（pc）;C *c31 = （C *）pthread_getspecific（pc）;C *c32 = （C *）pthread_getspecific（pc）;C *c33 = （C *）pthread_getspecific（pc）;C *c34 = （C *）pthread_getspecific（pc）;C *c35 = （C *）pthread_getspecific（pc）;C *c36 = （C *）pthread_getspecific（pc）;C *c37 = （C *）pthread_getspecific（pc）;C *c38 = （C *）pthread_getspecific（pc）;C *c39 = （C *）pthread_getspecific（pc）;C *c40 = （C *）pthread_getspecific（pc）;C