Dlouhy vypocet v PHP

function flushsql(&$sql,&$sqlvalues)
{
  $sql .= ";";
  $result = mysql_query ($sql, $GLOBALS["link"]);
  $sql = "INSERT INTO `dbdb`.`".$_SESSION["a"]['tbname']."` (`sec`, `us`, `amp`, `len`) VALUES ";
  $sqlvalues=0;          
}
 
 // ....

  // generujeme hity do db
  $hittime = new uTime;
  $sql = "INSERT INTO `dbdb`.`".$_SESSION["a"]['tbname']."` (`sec`, `us`, `amp`, `len`) VALUES ";
  $sqlvalues=0;
  $printed = 0;
  // vyrabime hity a ukladame je do db
  for ($i=0;$i<$_SESSION["aesrc"]['itvcnt'];$i++)
  {
    // pro kazdy interval
    $a = &$_SESSION["a"]['itv'][$i];
    for($t=$a["start"]->sec; $t<$a["end"]->sec; $t++)
    {
      // jdeme sekundu po sekunde
      $c = (float)(getfv($a, $t) + getfv($a, $t+1))/2.0;  // cetnost jako prumer funkcni hodnoty na zacatku a konci periody
      while ($c>=1.0)
      {
        $hittime->sec = $t;
        $hittime->us = (integer)((random_0_1()*1000000) + ($a["tvar"]*(random_0_1()-0.5))); //pridame neurcitost casu
        $hittime->Normalize();  // us musi byt v intrvalu <0,1000000)
        $amp = random_0_1()* ($a["ampmax"] - $a["ampmin"]) + $a["ampmin"]; // amp nahodne v zadanem intervalu
        if ($hittime->sec > $a["start"]->sec && $hittime->sec < $a["end"]->sec)  // hity ktere padnou mimo zadany interval ignorujeme
        {
          if ($sqlvalues>0) $sql .= ", ";
          $sql .= "(FROM_UNIXTIME(".$hittime->sec."), '".$hittime->us."', '".$amp."', '".(integer)($amp*100)."')";
          $sqlvalues++;
          if ($sqlvalues>100)
            flushsql($sql,$sqlvalues);
        }
        $c -= 1.0;
      }
      if (random_0_1()<$c) // mene nez jedna za sekundu
      {
        $hittime->sec = $t;
        $hittime->us = (integer)(random_0_1()*1000000 + ($a["tvar"]*(random_0_1()-0.5))); //pridame neurcitost casu
        $amp = random_0_1()* ($a["ampmax"] - $a["ampmin"]) + $a["ampmin"];
        if ($hittime->sec>$a["start"]->sec && $hittime->sec<$a["end"]->sec)
        {
          if ($sqlvalues>0) $sql .= ", ";
          $sql .= "(FROM_UNIXTIME(".$hittime->sec."), '".$hittime->us."', '".$amp."', '".(integer)($amp*100)."')";
          $sqlvalues++;
          if ($sqlvalues>100)
            flushsql($sql,$sqlvalues);
        }
      }
      if (time() >= $printed + 3) 
      { // aktualizace počítadla nejdříve za tři vteřiny
        echo "<script type='text/javascript'>document.getElementById('counter').innerHTML = 'Interval:".$i.", Cas:".$t."';</script><noscript>.</noscript>\n";
        ob_flush();
        flush();
        $printed = time();
      }
    }
    if ($sqlvalues>0)
      flushsql($sql,$sqlvalues);
  }
  // tady by mela byt db naplnena