/****************************************************************
* 说明: 用不同的方法，测试写文件的速度，测试结果表明
* 改变COUNT的值，将改变写入文件的大小
* 测试CPU使用率方法： /usr/bin/time -f "CPU: %P" ./a.out 1
* ************************************************************/
#include <cstdio>
#include <time.h>
#include <iostream>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <malloc.h>
#include <sys/time.h>
using namespace std;
#define WRITE_FILE /*定义这个宏，则把数据写到文件，否则不写，用于测试不写文件用的时间*/
const unsigned short usPageSize = 4*1024; /*4K*/
const unsigned long STR_LEN = (usPageSize*1024) +1; /*每次缓存4M有效数据写入文件 ，最后一个字节保证 null-terminated ，不写入文件*/
const unsigned long COUNT = 256; /*改变COUNT的值，将改变写入文件的大小 256 --->1G 16 ---> 64M 请问 为什么512 2G出现总线错误？ */
char g_strUserFlow[2048] ;
/****************************************************************
* 功能: 用fprintf，测试写文件速度
* ************************************************************/
void fprintf_write1();
/****************************************************************
* 功能: 用fwrite，（使用系统缓存）测试写文件速度
* ************************************************************/
void fwrite_write2();
/****************************************************************
* 功能: 用fwrite（自己分配4M缓存，每次写入4M, 然后fflush），测试写文件速度
* ************************************************************/
void fwrite_write2_1();
/****************************************************************
* 功能: 用write, 设O_DIRECT,自己维护缓存， ,测试写文件速度
* ************************************************************/
void write_direct3();
/****************************************************************
* 功能: 用write,（使用系统缓存），测试写文件速度
* ************************************************************/
void write_write4();
/****************************************************************
* 功能: 用write,（自己分配4M缓存，每次写入4M, 每次fsync），测试写文件速度
* ************************************************************/
void write_write4_1();
/****************************************************************
* 功能: 用mmap每次映射4M内存，测试写文件速度
* ************************************************************/
void mmap_write5();
/****************************************************************
* 功能: 用mmap每次一次性映射全部文件，测试写文件速度
* ************************************************************/
void mmap_write5_1();
/****************************************************************
* 功能: 用mmap每次映射1M内存，测试写文件速度
* ************************************************************/
void mmap_write5_2();
/****************************************************************
* 功能: 用mmap每次映射2M内存，测试写文件速度
* ************************************************************/
void mmap_write5_3();
//void cout_write8();
void setRecordData(char *pStrBuf, unsigned long ulBufSize, char *pStrLeftDataBuf, unsigned short &usDataBufSize);
int main(int argc, char *argv[])
{
int iFlowLen;
int iNum = 1;
if(2==argc && 0==strcmp("--help", argv[1]))
{
printf("\nusage:"
"\n\t run all : ./a.out "
"\n\t run fprintf_write1(): ./a.out 1"
"\n\t run fwrite_write2(): ./a.out 2"
"\n\t run fwrite_write2_1(): ./a.out 2.1"
"\n\t run write_direct3(): ./a.out 3"
"\n\t run write_write4(): ./a.out 4"
"\n\t run write_write4_1(): ./a.out 4.1"
"\n\t run mmap_write5(): ./a.out 5"
"\n\t run mmap_write5_1(): ./a.out 5.1"
"\n\t run mmap_write5_2(): ./a.out 5.2"
"\n\t run mmap_write5_3(): ./a.out 5.3\n"
);
exit(0);
}
if(3==argc)
{
iNum = atoi(argv[2]);
}
iFlowLen = sprintf(g_strUserFlow,
"%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s"
"\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s"
"\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s"
"\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s"
"\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s"
"\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s"
"\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s"
"\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s"
"\t%s\t%s\t%s\t\n",
"1319618698.0", "2011-10-26 16:44:58", "1319618697.0", "1319618698.0", "460030919115059",
"00a000002266f525", "", "", "Q d 8613309117677", "59",
"2", "0", "1", " -1", "G02",
"S38", "-1", "-1", "0", "-1",
"-1", "123", "115.168.25.12", "172.26.187.5", "366B0004",
"366B0004413E", "10.173.8.248", "10.0.0.200", "6", "52042",
"80", "102", "3000000", "14", "14",
"-", "-", "1", "8", "7",
"1362", "5230", "1362", "5230", "0",
"0", "0", "0", "0", "s.image.wap.soso.com",
"http://s.image.wap.soso.com/img/?p=320_416_0_0_0&src=httpFimg19.artxun.comap.g19.artxun.com2FsdaFoldimgFf0a22Ff0a27ad0c8fc34ca9758soso.com",
"0", "0", " 0", " -",
"-", "-", " -", "14", "14",
"0", "wap1", "0", "-", " -",
"-", "PDSN_02", "延安BSC2", "0", "0",
"", "-1", "", "-1", "-1",
"-1", "0", "-1", "1491300", "",
"0", "a8:c000:6380:0:ac1a:ba04:8b00:0/1200:a8c0:63:8000:ac:1aba:48b:670","-");
printf("filesize = %lu\n", COUNT*(STR_LEN-1));
#ifdef WRITE_FILE
printf("define WRITE_FILE\n\n");
#else
printf("not define WRITE_FILE\n\n");
#endif
while(iNum--)
{
if(1==argc)
{
fprintf_write1();
fwrite_write2();
fwrite_write2_1();
write_direct3();
write_write4();
write_write4_1();
mmap_write5();
mmap_write5_1();
mmap_write5_2();
mmap_write5_3();
}
else if(1 == atof(argv[1]))
{
fprintf_write1();
}
else if(2 == atof(argv[1]))
{
fwrite_write2();
}
else if(2.1 == atof(argv[1]))
{
fwrite_write2_1();
}
else if(3 == atof(argv[1]))
{
write_direct3();
}
else if(4 == atof(argv[1]))
{
write_write4();
}
else if(4.1 == atof(argv[1]))
{
write_write4_1();
}
else if(5 == atof(argv[1]))
{
mmap_write5();
}
else if(5.1 == atof(argv[1]))
{
mmap_write5_1();
}
else if(5.2 == atof(argv[1]))
{
mmap_write5_2();
}
else if(5.3 == atof(argv[1]))
{
mmap_write5_3();
}
}
//cout_write8();
}
double diffTime(struct timeval struStop, struct timeval struStart)
{
return ( (double)((1000000.0*struStop.tv_sec + struStop.tv_usec) - (1000000.0*struStart.tv_sec + struStart.tv_usec)) )/1000000.0;
}
void fprintf_write1()
{
int i = 0;
FILE *fp = NULL;
struct timeval struStart;
struct timeval struStop;
char strData[1024+1] = {0};
gettimeofday(&struStart, NULL);
unsigned long ulStart = clock();
fp = fopen("data.txt", "w+");
char strLeftData[2048] = {0};
unsigned short strSize = sizeof(strLeftData);
for (i =0; i< COUNT*usPageSize ; i++)
{
setRecordData(strData, 1024+1, strLeftData, strSize); // 每次写1024 ，'\0' 不写入
#ifdef WRITE_FILE
fprintf(fp, "%s", strData);
#endif
}
fclose(fp);
printf("fprintf_write1:\t %.3lf (clock time)\n", double(clock()-ulStart)/CLOCKS_PER_SEC);
gettimeofday(&struStop, NULL);
printf("all time diff: %.3lf\n\n", diffTime(struStop, struStart));
}
void fwrite_write2()
{
int i = 0;
FILE *fp = NULL;
unsigned long ulStart;
struct timeval struStart;
struct timeval struStop;
char strData[1024+1] = {0};
char strLeftData[2048] = {0};
unsigned short strSize = sizeof(strLeftData);
gettimeofday(&struStart, NULL);
ulStart = clock();
fp = fopen("data.txt", "w+");
for (i=0; i<COUNT*usPageSize; i++)
{
setRecordData(strData, 1024+1, strLeftData, strSize);
#ifdef WRITE_FILE
fwrite(strData, 1024, 1, fp);
#endif
}
fclose(fp);
printf("fwrite_write2:\t %.3lf (clock time),using system buffer\n", double(clock()-ulStart)/CLOCKS_PER_SEC);
gettimeofday(&struStop, NULL);
printf("all time diff: %.3lf\n\n", diffTime(struStop, struStart));
}
void fwrite_write2_1()
{
//char *pTmp = NULL;
int i;
//int j;
FILE *fp = NULL;
unsigned long ulStart;
struct timeval struStart;
struct timeval struStop;
char strData[STR_LEN] = {0}; //4M
char strLeftData[2048] = {0};
unsigned short strSize = sizeof(strLeftData);
gettimeofday(&struStart, NULL);
ulStart = clock();
fp = fopen("data.txt", "w+");
if (NULL == fp)
{
perror("Cannot open file : ");
return;
}
for (i=0; i<COUNT; i++)
{
setRecordData(strData, STR_LEN , strLeftData, strSize);
#ifdef WRITE_FILE
fwrite(strData, STR_LEN-1, 1, fp); // 每次写入4M
fflush(fp);
#endif
}
fclose(fp);
printf("fwrite_write2_1: %.3lf (clock time), allocate 4M, every time fflush()\n", double(clock()-ulStart)/CLOCKS_PER_SEC);
gettimeofday(&struStop, NULL);
printf("all time diff: %.3lf\n\n", diffTime(struStop, struStart));
return ;
}
void write_direct3()
{
//char strTmp[1024];
//char *pTmp = NULL;
int i;
int j;
int fd = -1, ret = -10;
unsigned long ulStart;
struct timeval struStart;
struct timeval struStop;
//char strData[STR_LEN] = {0};
char *buf = NULL;
char strLeftData[2048] = {0};
unsigned short strSize = sizeof(strLeftData);
//buf = (char *)valloc(1024*usPageSize);
posix_memalign((void**)&buf, usPageSize, STR_LEN );
//typedef char _aligned_char __attribute__ ((aligned (8192)));
//_aligned_char buf[1024*usPageSize];
gettimeofday(&struStart, NULL);
ulStart = clock();
fd = open("data.txt", O_RDWR |O_CREAT|O_DIRECT, 00600);
if (fd<0)
{
perror("Cannot open file : ");
return;
}
for (i=0; i<COUNT; i++)
{
memset(buf, 0, 1024*usPageSize);
setRecordData(buf, STR_LEN, strLeftData, strSize);
#ifdef WRITE_FILE
write(fd, buf, STR_LEN-1);
#endif
}
free(buf);
close(fd);
printf("write_direct3:\t %.3lf (clock time),using O_DIRECT, allocate 4M\n", double(clock()-ulStart)/CLOCKS_PER_SEC);
gettimeofday(&struStop, NULL);
printf("all time diff: %.3lf\n\n", diffTime(struStop, struStart));
return ;
}
void write_write4()
{
int i = 0;
int fd;
unsigned long ulStart;
struct timeval struStart;
struct timeval struStop;
char strData[1024+1] = {0};
char strLeftData[2048] = {0};
unsigned short strSize = sizeof(strLeftData);
gettimeofday(&struStart, NULL);
ulStart = clock();
fd = open("data.txt", O_CREAT | O_RDWR);
for (i=0; i<COUNT*usPageSize; i++)
{
setRecordData(strData, 1024+1 , strLeftData, strSize);
#ifdef WRITE_FILE
write(fd, strData, 1024);
#endif
}
close(fd);
printf("write_write4:\t %.3lf (clock time), using system buffer\n", double(clock()-ulStart)/CLOCKS_PER_SEC);
gettimeofday(&struStop, NULL);
printf("all time diff: %.3lf\n\n", diffTime(struStop, struStart));
}
void write_write4_1()
{
//char buf[1024*usPageSize]; //4M
int i;
int fd = -1, ret = -10;
unsigned long ulStart;
struct timeval struStart;
struct timeval struStop;
char strData[STR_LEN] = {0};
char strLeftData[2048] = {0};
unsigned short strSize = sizeof(strLeftData);
//memset(buf, 0, 1024*usPageSize);
gettimeofday(&struStart, NULL);
ulStart = clock();
fd = open("data.txt", O_RDWR |O_CREAT, 00600);
if (fd<0)
{
perror("Cannot open file : ");
return;
}
for (i=0; i<COUNT; i++)
{
setRecordData(strData, STR_LEN , strLeftData, strSize);
#ifdef WRITE_FILE
write(fd, strData, STR_LEN-1); /*一次写4M*/
fsync(fd);
#endif
}
close(fd);
printf("write_write4_1:\t %.3lf (clock time), alloc 4M buffer, every time using fsync()\n", double(clock()-ulStart)/CLOCKS_PER_SEC);
gettimeofday(&struStop, NULL);
printf("all time diff: %.3lf\n\n", diffTime(struStop, struStart));
return ;
}
void mmap_write5()
{
int i = 0, j = 0;
char *pMap = NULL;
int iPagesize;
int fd;
unsigned long ulStart;
struct timeval struStart;
struct timeval struStop;
char strData[STR_LEN] = {0};
char strLeftData[2048] = {0};
unsigned short strSize = sizeof(strLeftData);
//iPagesize = getpagesize();
gettimeofday(&struStart, NULL);
ulStart = clock();
fd = open("data.txt",O_RDWR|O_CREAT,00600);
ftruncate(fd, COUNT*(STR_LEN-1));
#ifndef WRITE_FILE
pMap = (char *)calloc(1, STR_LEN-1);
#endif
for (i = 0; i < COUNT; i++)
{
#ifdef WRITE_FILE
pMap = (char *)mmap(0,STR_LEN-1, PROT_WRITE, MAP_SHARED, fd, i*(STR_LEN-1)); // 每次打开4M
if(MAP_FAILED == pMap)
{
perror("mmap_write5 error mmap() :");
return;
}
//ftruncate(fd, i*(STR_LEN-1) + (STR_LEN-1) );
#endif
setRecordData(strData, STR_LEN , strLeftData, strSize);
memcpy(pMap , strData, STR_LEN-1);
#ifdef WRITE_FILE
munmap(pMap, STR_LEN-1);
#endif
}
close(fd);
#ifndef WRITE_FILE
free(pMap);
#endif
printf("mmap_write5: %.3lf (clock time), mmap: 4M buffer\n", double(clock()-ulStart)/CLOCKS_PER_SEC);
gettimeofday(&struStop, NULL);
printf("all time diff: %.3lf\n\n", diffTime(struStop, struStart));
}
void mmap_write5_1()
{
int i = 0, j = 0;
char *pMap = NULL;
int iPagesize;
int fd;
unsigned long ulStart;
struct timeval struStart;
struct timeval struStop;
char strData[STR_LEN] = {0};
char strLeftData[2048] = {0};
unsigned short strSize = sizeof(strLeftData);
//iPagesize = getpagesize();
gettimeofday(&struStart, NULL);
ulStart = clock();
#ifndef WRITE_FILE
pMap = (char *)calloc(1, 1024*usPageSize*COUNT);
if(NULL==pMap)
{
printf("pMap calloc error\n\n");
return;
}
#endif
fd = open("data.txt",O_RDWR|O_CREAT,00600);
#ifdef WRITE_FILE
pMap = (char *)mmap(0,(STR_LEN-1)*COUNT, PROT_WRITE, MAP_SHARED, fd, 0); // 一次全部打开文件映射（内存要求）
ftruncate(fd, (STR_LEN-1)*COUNT );
#endif
for (j=0; j<COUNT; j++)
{
setRecordData(strData, STR_LEN , strLeftData, strSize);
memcpy(pMap + j*(STR_LEN-1), strData, STR_LEN-1);
}
#ifdef WRITE_FILE
munmap(pMap, (STR_LEN-1)*COUNT);
#endif
close(fd);
#ifndef WRITE_FILE
free(pMap);
#endif
printf("mmap_write5_1:\t %.3lf (clock time), mmap: all buffer\n", double(clock()-ulStart)/CLOCKS_PER_SEC);
gettimeofday(&struStop, NULL);
printf("all time diff: %.3lf\n\n", diffTime(struStop, struStart));
}
void mmap_write5_2()
{
int i = 0;
char *pMap = NULL;
int iPagesize;
int fd;
unsigned long ulStart;
struct timeval struStart;
struct timeval struStop;
char strData[STR_LEN] = {0};
char strLeftData[2048] = {0};
unsigned short strSize = sizeof(strLeftData);
gettimeofday(&struStart, NULL);
ulStart = clock();
#ifndef WRITE_FILE
pMap = (char *)calloc(1, (STR_LEN-1)/4);
#endif
fd = open("data.txt",O_RDWR|O_CREAT,00600);
ftruncate(fd, COUNT*(STR_LEN-1));
for (i = 0; i < 4*COUNT; i++)
{
#ifdef WRITE_FILE
pMap = (char *)mmap(0,(STR_LEN-1)/4, PROT_WRITE, MAP_SHARED, fd, i*(STR_LEN-1)/4); // 每次打开1M
//ftruncate(fd, i*(STR_LEN-1)/4 + (STR_LEN-1)/4 );
#endif
setRecordData(strData, (STR_LEN-1)/4 +1 , strLeftData, strSize);
memcpy(pMap , strData, (STR_LEN-1)/4);
#ifdef WRITE_FILE
munmap(pMap, (STR_LEN-1)/4);
#endif
}
close(fd);
#ifndef WRITE_FILE
free(pMap);
#endif
printf("mmap_write5_2: %.3lf(clock time) (clock time), mmap: 1M buffer\n", double(clock()-ulStart)/CLOCKS_PER_SEC);
gettimeofday(&struStop, NULL);
printf("all time diff: %.3lf\n\n", diffTime(struStop, struStart));
}
void mmap_write5_3()
{
int i = 0;
char *pMap = NULL;
int iPagesize;
int fd;
unsigned long ulStart;
struct timeval struStart;
struct timeval struStop;
char strData[STR_LEN] = {0};
char strLeftData[2048] = {0};
unsigned short strSize = sizeof(strLeftData);
gettimeofday(&struStart, NULL);
ulStart = clock();
#ifndef WRITE_FILE
pMap = (char *)calloc(1, 512*usPageSize);
#endif
fd = open("data.txt",O_RDWR|O_CREAT,00600);
ftruncate(fd, COUNT*(STR_LEN-1));
for (i = 0; i < 2*COUNT; i++)
{
#ifdef WRITE_FILE
pMap = (char *)mmap(0,(STR_LEN-1)/2, PROT_WRITE, MAP_SHARED, fd, i*(STR_LEN-1)/2); // 每次打开2M
//ftruncate(fd, i*(STR_LEN-1)/2 + (STR_LEN-1)/2 );
#endif
setRecordData(strData, (STR_LEN-1)/2 +1 , strLeftData, strSize);
memcpy(pMap , strData, (STR_LEN-1)/2);
#ifdef WRITE_FILE
munmap(pMap, (STR_LEN-1)/2);
#endif
}
close(fd);
#ifndef WRITE_FILE
free(pMap);
#endif
printf("mmap_write5_3: %.3lf (clock time), mmap: 2M buffer\n", double(clock()-ulStart)/CLOCKS_PER_SEC);
gettimeofday(&struStop, NULL);
printf("all time diff: %.3lf\n\n", diffTime(struStop, struStart));
}
void setRecordData(char *pStrBuf, unsigned long ulBufSize, char *pStrLeftDataBuf, unsigned short &usDataBufSize)
{
unsigned long ulLeftBufLen = ulBufSize;
short sCopyLen = 0;
unsigned short usLeftCharLen = 0;
char *pStrBufTmp = pStrBuf;
char *pStrTmp = pStrLeftDataBuf;
if (NULL==pStrBuf || NULL==pStrLeftDataBuf)
{
return ;
}
sCopyLen = snprintf(pStrBufTmp, ulLeftBufLen, pStrTmp);
if(sCopyLen<0)
{
perror("snprintf error: ");
return ;
}
if( sCopyLen < ulLeftBufLen-1 )
{
ulLeftBufLen = ulLeftBufLen - sCopyLen;
pStrBufTmp += sCopyLen;
pStrTmp = g_strUserFlow;
while(ulLeftBufLen > 0)
{
sCopyLen = snprintf(pStrBufTmp, ulLeftBufLen, pStrTmp);
if(sCopyLen<0)
{
perror("snprintf error: ");
return;
}
if( sCopyLen < ulLeftBufLen-1 )
{
ulLeftBufLen = ulLeftBufLen - sCopyLen;
pStrBufTmp += sCopyLen;
}
else
{
break;
}
}
}
/*剩下的拷到pStrLeftDataBuf*/
strncpy(pStrLeftDataBuf, pStrTmp + (ulLeftBufLen-1), usDataBufSize-1 ); /*确保：pStrLeftDataBuf[usDataBufSize-1] = '\0'*/
}
写文件速度测试：
函数写文件方法简介：
1，void fprintf_write1()
用fprintf函数写文件，测试写文件速度。
2，void fwrite_write2()
用fwrite函数写文件，使用系统缓存，测试写文件速度。
3，void fwrite_write2_1(),
用fwrite函数写文件，自己分配4M缓存，每次写入4M，然后调用fflush，测试写文件速度。
4，void write_direct3();
用write写文件，设0_DIRECT,自己维护4M的缓存，测试写文件速度。
5，void write_write4();
用write写文件，使用系统缓存，测试写文件速度。,
6，voidwrite_write4_1();
用write写文件，自己分配4M缓存，每次写入4M，然后调用fsync，测试写文件速度。,
7，voidmmap_write5();
用mmap每次映射4M内存，测试写文件速度。
8，void mmap_write5_1();
用mmap每次映射全部文件大小的内存，测试写文件速度。
9，voidmmap_write5_2();
用mmap每次映射1M内存，测试写文件速度。,
10，void mmap_write5_3();
用mmap每次映射2M内存，测试写文件速度。
测试命令：/usr/bin/time -f "CPU: %P" ./a.out 1
测试结果：1，写入文件大小：1G
函数名 |
Clock()差值 |
实际时间 |
CPU使用率(%) |
|
fprintf_write1() avg(实际时间) = 16.255 |
9.160 8.870 8.090 |
15.329 17.706 15.729 |
59 49 51 |
|
fwrite_write2() avg(实际时间) = 18.676 |
10.860 8.320 9.050 |
18.775 20.639 16.615 |
57 40 53 |
|
fwrite_write2_1(), avg(实际时间) = 16.714 |
6.830 4.230 4.270 |
17.414 16.067 16.660 |
38 26 25 |
|
write_direct3(); avg(实际时间) = 19.290 |
2.130 2.050 1.920 |
19.897 18.707 19.266 |
10 10 9 |
|
write_write4(); avg(实际时间) =58.363 |
23.840 23.870 24.700 |
58.632 58.123 58.333 |
40 41 42 |
|
write_write4_1(); avg(实际时间) = 24.918 |
4.670 4.320 3.850 |
21.260 31.874 21.621 |
21 13 17 |
|
mmap_write5() avg(实际时间) = 16.794 |
5.230 5.750 5.760 |
16.672 16.019 17.692 |
31 35 32 |
|
mmap_write5_1() avg(实际时间) = 55.473 |
8.360 7.680 8.670 |
58.568 53.894 53.958 |
14 14 16 |
|
mmap_write5_2() avg(实际时间) =14.954 |
4.920 5.200 5.290 |
14.862 15.911 14.088 |
32 32 37 |
|
mmap_write5_3() avg(实际时间) =16.317 |
5.210 5.270 5.010 |
15.451 15.746 17.759 |
33 33 28 |
结果：mmap_write5_2()最快
2，写入文件大小：64M
函数名 |
Clock()差值 |
实际执行时间 |
CPU使用率(%) |
|
|
fprintf_write1() avg(实际时间) =0.940 |
0.790 0.460 0.440 |
1.404 0.726 0.691 |
55 65 63 |
|
|
fwrite_write2() avg(实际时间) =0.723 |
0.650 0.440 0.430 |
0.819 0.668 0.682 |
79 66 63 |
|
|
fwrite_write2_1() avg(实际时间) =0.327 |
0.330 0.190 0.190 |
0.407 0.290 0.285 |
79 67 64 |
|
|
write_direct3() avg(实际时间) =0.915 |
0.150 0.150’ 0.130 |
0.928 0.893 0.923 |
17 17 15 |
|
|
write_write4() avg(实际时间) =0.773 |
0.610 0.500 0.510 |
0.889 0.711 0.718 |
69 70 71 |
|
|
write_write4_1() avg(实际时间) =1.262 |
0.370 0.240 0.190 |
1.433 1.213 1.139 |
26 21 17 |
|
|
mmap_write5() avg(实际时间) =0.315 |
0.330 0.180 0.180 |
0.406 0.268 0.271 |
81 64 65 |
|
|
mmap_write5_1() avg(实际时间) =0.357 |
0.360 0.220 0.230 |
0.465 0.290 0.316 |
79 73 72 |
|
|
mmap_write5_2() avg(实际时间) =0.287 |
0.200 0.190 0.180 |
0.289 0.292 0.282 |
65 65 61 |
|
|
mmap_write5_3() avg(实际时间) =0.345 |
0.390 0.190 0.190 |
0.471 0.291 0.275 |
81 63 67 |
|
结果：mmap_write5_2()最快
总结： 用mmap每次映射1M内存，测试得到最快速度。