Hi Hitoshi,
On 2013/6/7 21:50, Hitoshi Mitake wrote:
> At Fri, 7 Jun 2013 09:26:58 +0800,
> Jianguo Wu wrote:
>>
>> Hi Hitoshi,
>>
>> Thanks for your reply! please see below.
>>
>> On 2013/6/6 21:54, Hitoshi Mitake wrote:
>>
>>> Hi Jianguo,
>>>
>>> On Wed, Jun 5, 2013 at 12:26 PM, Jianguo Wu <wujianguo@xxxxxxxxxx> wrote:
>>>> Hi,
>>>> One more question, I wrote a memcpy test program, mostly the same as with perf bench memcpy.
>>>> But test result isn't consistent with perf bench when THP is off.
>>>>
>>>> my program perf bench
>>>> THP: 3.628368 GB/Sec (with prefault) 3.672879 GB/Sec (with prefault)
>>>> NO-THP: 3.612743 GB/Sec (with prefault) 6.190187 GB/Sec (with prefault)
>>>>
>>>> Below is my code:
>>>> src = calloc(1, len);
>>>> dst = calloc(1, len);
>>>>
>>>> if (prefault)
>>>> memcpy(dst, src, len);
>>>> gettimeofday(&tv_start, NULL);
>>>> memcpy(dst, src, len);
>>>> gettimeofday(&tv_end, NULL);
>>>>
>>>> timersub(&tv_end, &tv_start, &tv_diff);
>>>> free(src);
>>>> free(dst);
>>>>
>>>> speed = (double)((double)len / timeval2double(&tv_diff));
>>>> print_bps(speed);
>>>>
>>>> This is weird, is it possible that perf bench do some build optimize?
>>>>
>>>> Thansk,
>>>> Jianguo Wu.
>>>
>>> perf bench mem memcpy is build with -O6. This is the compile command
>>> line (you can get this with make V=1):
>>> gcc -o bench/mem-memcpy-x86-64-asm.o -c -fno-omit-frame-pointer -ggdb3
>>> -funwind-tables -Wall -Wextra -std=gnu99 -Werror -O6 .... # ommited
>>>
>>> Can I see your compile option for your test program and the actual
>>> command line executing perf bench mem memcpy?
>>>
>>
>> I just compiled my test program with gcc -o memcpy-test memcpy-test.c.
>> I tried to use the same compile option with perf bench mem memcpy, and
>> the test result showed no difference.
>>
>> My execute command line for perf bench mem memcpy:
>> #./perf bench mem memcpy -l 1gb -o
>
> Thanks for your information. I have three more requests for
> reproducing the problem:
>
> 1. the entire source code of your program
Please see the attachment.
> 2. your gcc version
4.3.4
> 3. your glibc version
glibc-2.11.1-0.17.4
Thanks,
Jianguo Wu
>
> I should've requested it first, sorry :(
>
> Thanks,
> Hitoshi
>
> .
>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/time.h>
#include <unistd.h>
#define K 1024LL
#define print_bps(x) do { \
if (x < K) \
printf(" %14lf B/Sec", x); \
else if (x < K * K) \
printf(" %14lfd KB/Sec", x / K); \
else if (x < K * K * K) \
printf(" %14lf MB/Sec", x / K / K); \
else \
printf(" %14lf GB/Sec", x / K / K / K); \
} while (0)
long long local_atoll(const char *str)
{
unsigned int i;
long long length = -1, unit = 1;
if (!isdigit(str[0]))
goto out_err;
for (i = 1; i < strlen(str); i++) {
switch (str[i]) {
case 'B':
case 'b':
break;
case 'K':
if (str[i + 1] != 'B')
goto out_err;
else
goto kilo;
case 'k':
if (str[i + 1] != 'b')
goto out_err;
kilo:
unit = K;
break;
case 'M':
if (str[i + 1] != 'B')
goto out_err;
else
goto mega;
case 'm':
if (str[i + 1] != 'b')
goto out_err;
mega:
unit = K * K;
break;
case 'G':
if (str[i + 1] != 'B')
goto out_err;
else
goto giga;
case 'g':
if (str[i + 1] != 'b')
goto out_err;
giga:
unit = K * K * K;
break;
case 'T':
if (str[i + 1] != 'B')
goto out_err;
else
goto tera;
case 't':
if (str[i + 1] != 'b')
goto out_err;
tera:
unit = K * K * K * K;
break;
case '\0': /* only specified figures */
unit = 1;
break;
default:
if (!isdigit(str[i]))
goto out_err;
break;
}
}
length = atoll(str) * unit;
goto out;
out_err:
length = -1;
out:
return length;
}
static double timeval2double(struct timeval *ts)
{
return (double)ts->tv_sec +
(double)ts->tv_usec / (double)1000000;
}
void do_memcpy(long long len, int prefault)
{
void *src, *dst;
struct timeval tv_start, tv_end, tv_diff;
double res;
src = calloc(1, len);
dst = calloc(1, len);
if (prefault)
memcpy(dst, src, len);
gettimeofday(&tv_start, NULL);
memcpy(dst, src, len);
gettimeofday(&tv_end, NULL);
timersub(&tv_end, &tv_start, &tv_diff);
free(src);
free(dst);
res = (double)((double)len / timeval2double(&tv_diff));
print_bps(res);
if (prefault)
printf("\t(with prefault)");
printf("\n");
}
int main(int argc, char *argv[])
{
long long len = -1;
char ch;
int prefault = 0;
while( (ch=getopt(argc, argv, "l:") ) != -1 )
{
switch(ch)
{
case 'l':
len = local_atoll(optarg);
if (len < 0) {
printf("Invalid size\n");
return 0;
} else
printf("# Copying %s Byte ...\n", optarg);
break;
default:
return;
}
}
do_memcpy(len, 1);
return 0;
}