Code: Select all

#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/mman.h>
#include <unistd.h>

int
TimeNow(void)
{
   struct timeval tv;
   struct timezone tz;
   (void) gettimeofday(&tv, &tz);
   return tv.tv_sec * 1000 + tv.tv_usec / 1000;
}

int main(int argc, char *argv[])
{
    char *buffer;
    struct stat buf;
    int fh, err;

    unsigned int chunk;

    if(argc < 2)
        goto err;

    fh = open(argv[1], O_RDONLY);
    if(fh == -1)
        goto err;

    err = fstat(fh,&buf);

    if (err != 0)
        goto err;

    printf("file size is %ld\n",buf.st_size);

    buffer = malloc(64*1024*1024);
    if(buffer == NULL)
        goto err1;

    for(chunk = 512; chunk <= 64*1024*1024; chunk<<=1)
    {
        long pos;
        int end_time;
        unsigned long long iter;
        unsigned long long total;
        int tmp;
        char *str;

        pos = lseek(fh, 0L, SEEK_SET);
        if (pos == -1L)
            goto err2;

        end_time = TimeNow()+16000;

        iter = 0;
        do
        {
            read(fh, buffer,chunk);
            pos += chunk;
            iter++;
            if( pos >= 64*1024*1024)
            {
                pos = lseek(fh, 0L, SEEK_SET);
                if (pos == -1L)
                    goto err2;
            }
        }while (end_time > TimeNow());

        total = chunk*iter/16384;
        if(chunk >= 1024*1024)
        {
            tmp = chunk >> 20;
            str = "MB";
        }
        else if(chunk >= 1024)
        {
            tmp = chunk >> 10;
            str = "KB";
        }
        else
        {
            tmp = chunk;
            str = "";
        }

        printf("chunk %d %s iterations %llu speed %llu KB/s\n", tmp, str, iter, total);
    }

    return 0;

err:
    printf("Usage fspeed testfile\n");

    return 0;

err1:
    printf("No enough memory for read buffer\n");
    close(fh);
    return 0;

err2:
    printf("lseek to beginning failed\n");
    free(buffer);
    close(fh);

    return 0;
}