Re^3: MySQL Query Time DBI

[zebedee]

Illuminatus is correct - the time comes from the mysql command client.

Not that it helps the OP, but I was interested in finding out about this (and one of the key points of Open Source is that you CAN look at the source!)

(Based on MySQL 5.0.51a, OpenBSD port)

client/mysql.cc

(around line 2049)

static int
com_go(String *buffer,char *line __attribute__((unused)))
{
  char          buff[200], time_buff[32], *pos;

(line 2092)  timer=start_timer();

(line 2137)      mysql_end_timer(timer,time_buff);

(line 2170 - the "n rows in set" message)

        sprintf(buff,"%ld %s in set",
                (long) mysql_num_rows(result),
                (long) mysql_num_rows(result) == 1 ? "row" : "rows");

(line 2195)     strmov(pos, time_buff);

So, what does mysql_end_timer put in time_buff?

(line 3726, same file, builds the "(" and ")", calling nice_time for the seconds display)

static void end_timer(ulong start_time,char *buff)
{
  nice_time((double) (start_timer() - start_time) /
            CLOCKS_PER_SEC,buff,1);
}
       
       
static void mysql_end_timer(ulong start_time,char *buff)
{
  buff[0]=' ';
  buff[1]='(';
  end_timer(start_time,buff+2);
  strmov(strend(buff),")");
}

(line 3695 - builds the "n sec" part)

static void nice_time(double sec,char *buff,bool part_second)
{
  ulong tmp;
  if (sec >= 3600.0*24)
  {
    tmp=(ulong) floor(sec/(3600.0*24));
    sec-=3600.0*24*tmp;
    buff=int10_to_str((long) tmp, buff, 10);
    buff=strmov(buff,tmp > 1 ? " days " : " day ");
  }
  if (sec >= 3600.0)
  {
    tmp=(ulong) floor(sec/3600.0);
    sec-=3600.0*tmp;
    buff=int10_to_str((long) tmp, buff, 10);
    buff=strmov(buff,tmp > 1 ? " hours " : " hour ");
  }
  if (sec >= 60.0)
  {
    tmp=(ulong) floor(sec/60.0);
    sec-=60.0*tmp;
    buff=int10_to_str((long) tmp, buff, 10);
    buff=strmov(buff," min ");
  }
  if (part_second)
    sprintf(buff,"%.2f sec",sec);
  else
    sprintf(buff,"%d sec",(int) sec);
}

And, so, finally, what does start_timer() do? (line 3684)

static ulong start_timer(void)
{
#if defined( __WIN__) || defined( OS2) || defined(__NETWARE__)
 return clock();
#else
  struct tms tms_tmp;
  return times(&tms_tmp);
#endif
}

Assuming we are not running on WIN/OS2/NETWARE, we can see what times does:

http://www.openbsd.org/cgi-bin/man.cgi?query=times&apropos=0&sektion=0&manpath=OpenBSD+Current&arch=i386&format=html

BUT converting this into Perl is for another day!