问在用C编写大量文件后Ubuntu冻结

EN

#define MEM_LEN 50000 
#define FILE_LEN 10000*300

struct log_format {
        long cnt;
        long tv_sec;
        long tv_nsec;
        unsigned int user;
        char rw;
        char pathbuffer[256];
        size_t count;
        long long pos;
};

int main(int argc, const char *argv[])
{
    int fd=0;
    struct log_format *addr  = NULL;
    int i=0;
    FILE *file;
    char filestr[20];
    int data_cnt = 0;
    int file_cnt =0;

    // open shared memory device //
    fd = open("/dev/remap_pfn", O_RDWR);
    if (fd < 0) {
        perror("....open shared memory device1 failed\n");
        exit(-1);   }
    // memory mapping to shared memory device //
    addr = mmap(NULL, BUF_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_LOCKED, fd, OFFSET);
    if (!addr) {
        perror("....mmap1 failed\n");
        exit(-1);   }

    // open a file //
    sprintf(filestr, "%d.csv", file_cnt);
    file = fopen(filestr, "w");
    printf("%s created\n",filestr);

    // continuously check the memory replacement of last, and write to file // 
    while(1){

        fprintf(file, "%lu,%lu,%lu,%u,%c,%s,%zu,%lld\n", addr[i].cnt, addr[i].tv_sec,
                                addr[i].tv_nsec, addr[i].user, addr[i].rw, addr[i].pathbuffer,
                                addr[i].count, addr[i].pos);
        i++;
        data_cnt++;
        if(i>=MEM_LEN)
            i=0;

        // when reaching a threshold, create another file to write //
        if(data_cnt>=FILE_LEN){
            data_cnt = 0;
            fclose(file);
            file_cnt++;

            // open a file //
            sprintf(filestr, "%d.csv", file_cnt);
            file = fopen(filestr, "w");
            printf("%s created\n",filestr);
        }
    }

    fclose(file);   

    return 0;
}