[SE] ½Ã½ºÅÛ ºÎÆà ½Ã°¢¹× ½Ã°£ ¾Ë¾Æº¸±â

 - ÀÛ¼ºÀÚ : ±èÄ¥ºÀ <san2(at)linuxchannel.net>
 - ÀÛ¼ºÀÏ : 2002.11.09
 - ºÐ ·ù  : ½Ã½ºÅÛ°ü¸®(SE)
 - ¼ö ÁØ  : Ãʺ¸
 - ³» ¿ë  : ½Ã½ºÅÛ ºÎÆà ½Ã°¢(½ÃÁ¡)°ú ½Ã°£À» ¾Ë¾Æº¸´Â ¹æ¹ý
 - Å°¿öµå : uptime, last, /proc/uptime, /proc/stat, perl, PHP

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ÀÌ ¹®¼­¿¡ ´ëÇÑ ÃֽŠ³»¿ëÀº ¾Æ·¡ URL¿¡¼­ È®ÀÎÇÒ ¼ö ÀÖ½À´Ï´Ù.

http://www.linuxchannel.net/docs/sys-uptime.txt


[¹æ¹ý1] uptime ¸í·É¾î

°¡Àå °£´ÜÇÑ ¹æ¹ýÀÔ´Ï´Ù.

# uptime
  9:01pm  up  2:12,  1 user,  load average: 0.00, 0.00, 0.00
#

ÇöÀç Á¦ ½Ã½ºÅÛÀº ºÎÆÃÈÄ 2½Ã°£ 12ºÐ Áö³µ±º¿ä.. À§ÀÇ ¿ÀÈÄ 9½Ã 01ºÐºÎÅÍ ¿ªÀ¸·Î °Å½½·¯
¿Ã¶ó°¡¸é ºÎÆà ½Ã°¢À» ¾Ë ¼ö ÀÖ°ÚÁÒ.... (°è»êÇÏÁö ¸¶¼¼¿ä. T.T)


[¹æ¹ý2] last ¸í·É¾î

# last | grep boot | head -n 1
reboot   system boot  2.4.19-R2   Sat Nov  9 18:50   (02:12)
#

Á¦ÀÏ ¸¶Áö¸·ÀÇ (02:12) °ªÀÌ ½Ã½ºÅÛ uptime ÀÔ´Ï´Ù. Áï 2½Ã°£ 12ºÐ Áö³µ´Ù´Â ÀǹÌÀÔ´Ï´Ù.
±×¸®°í 'Sat Nov  9 18:50'Àº ½Ã½ºÅÛ boot time ÀÔ´Ï´Ù.


[¹æ¹ý3] /proc/uptime ÀÌ¿ë

# cat /proc/uptime
7979.84 7961.31
#

ù¹ø° °ªÀº ½Ã½ºÅÛÀÌ ºÎÆÃÈÄ ÇöÀç ½Ã°¢±îÁöÀÇ ºÎÆà ½Ã°£À» ÃÊ´ÜÀ§·Î Ç¥½ÃÇÑ sytem uptime
°ªÀÔ´Ï´Ù. µÎ¹ø° °ªÀº 'idle uptime' ÀÔ´Ï´Ù.
(reference : /usr/src/linux/fs/proc/proc_misc.c)

À§ÀÇ 7979 Ãʸ¦ °è»êÇÏ´Ï ½Ã½ºÅÛÀÌ ºÎÆõÈÁö ¾à 2½Ã°£ 13ºÐÀ̵Ǿú±º¿ä.
(uptime ¸í·É¾î·Î È®ÀÎÇÏ¸é °ÅÀÇ °°Àº °ªÀÓ)

±×·³ Á»´õ Á¤È®ÇÏ°Ô ºÎÆà ½Ã°¢À» °è»êÇØ º¾½Ã´Ù.
ºÎÆÃÈÄ ±¸µ¿ ½Ã°£ÀÌ 7979ÃÊÀ̹ǷΠÇöÀç UNIX timestamp °ª¿¡¼­ 7979Ãʸ¦ »©¸é
ºÎÆýÃÁ¡ÀÇ Unix timestamp °ªÀÌ °è»êµÇÁÒ.. ÀÌ °ªÀ» perlÀÇ gmdate()À̳ª PHPÀÇ data()
ÇÔ¼ö¸¦ ÀÌ¿ëÇÏ¸é ½±°Ô ºÎÆýÃÁ¡ÀÇ ½Ã°¢À» ¾Ë ¼ö ÀÖ½À´Ï´Ù(C´Â »ý·«).

-- uptime.pl -------------------------------------------------------
#!/usr/bin/perl
#
#
open(UPTIME, '/proc/uptime') or die "Can't open /proc/uptime\n";
while(<UPTIME>) {
  @uptime = $_; ## to array
}
close(UPTIME);

$btime = time() - int $uptime[0];
$btime = gmtime($btime + (3600*9)); ## GMT+9

print "boot time : $btime\n";

exit 0;
-------------------------------------------------------------------

(½ÇÇà °á°ú)
# perl uptime.pl
boot time : Sat Nov  9 18:49:55 2002
#

-- uptime.php ------------------------------------------------------
<?php
$uptime = file('/proc/uptime');
$btime = time() - (int)$uptime[0];

echo 'boot time: ' . date('Y.m.d H:i:s',$btime);
?>
-------------------------------------------------------------------

<ÆÁ> ½Ç½Ã°£(1ÃÊ°£°Ý)À¸·Î uptime º¸±â
# watch -n 1 cat /proc/uptime
Á¾·á´Â 'Ctrl + C'
</ÆÁ>

<Âü°í> PHP sysinfo(http://ftp.linuxchannel.net/devel/sysinfo.tar)
ÃÖ±Ù ¹öÀü¿¡´Â boot timeÀ» Ãß°¡µÇ¾ú½À´Ï´Ù.
</Âü°í>


[¹æ¹ý4] /proc/stat ÀÌ¿ë

# cat /proc/stat
cpu  1221 0 639 767372
cpu0 1221 0 639 767372
page 36710 5580
swap 1 0
intr 785185 769232 9 0 0 0 1 3 0 0 7363 8173 0 356 0 0 48
disk_io: (8,0):(3697,2449,73190,1248,11048) 
ctxt 177800
btime 1036835394
processes 753
#

8¹ø° Ç׸ñÀÇ btime °ª(1036835394)ÀÌ ¹Ù·Î ºÎÆýÃÀÇ UNIX timestamp °ªÀÔ´Ï´Ù.
ÀÌ °ªÀº [¹æ¹ý3]¿¡¼­ °è»êÇÑ $btime °ª°ú °°½À´Ï´Ù(¿ÀÂ÷1ÃÊ).
¹Ù²Ù¾î ¸»Çϸé ÇöÀç UNIX timestamp °ª¿¡¼­ ÀÌ btime °ªÀ» »©¸é ½Ã½ºÅÛ uptime °ªÀÌ
³ª¿É´Ï´Ù. ÀÌ uptime °ªÀº [¹æ¹ý3]¿¡¼­ ¾òÀº $uptime[0] °ª°ú °°½À´Ï´Ù.

À̹ø¿¡´Â ÀÌ btime °ªÀ» ¾ò¾î¼­ boot timeÀ» Ãâ·ÂÇÏ°í uptime °ªÀ» °è»êÇÏ¿© Àбâ
ÆíÇÏ°Ô Ãâ·ÂÇØ º¾½Ã´Ù.

-- uptime2.pl -------------------------------------------------------
#!/usr/bin/perl
#
# reference : http://www.blackplasma.net/scripts/load
#
open(STAT, '/proc/stat') or "Can't open /proc/stat\n";
$i = 0;
while(<STAT>) {
  $stat[$i] = $_;
  $i++;
}
close(STAT);

$stat[7] =~ s/[^\d]+//g; ## change boot time(UNIX timestamp)
$btime = gmtime($stat[7] + (3600*9));
$term = time() - $stat[7];
$uptime = &runtime($term);

print "boot time\t: $btime\n";
print "system uptime\t: $uptime\n";

sub runtime
{
  my($term) = @_;

  $days  = int($term / 86400);
  $secs  = int($term % 86400);
  $hours = int($secs / 3600);
  $secs  = int($secs % 3600);
  $mins  = int($secs / 60);
  $secs  = int($secs % 60);

  $days = $days ? "${days}days" : '';
  $hours = $hours ? " ${hours}hours" : '';
  $mins = $mins ? " ${mins}minutes " : '';
  $secs .= 'seconds';

  return "$days$hours$mins$secs";
}

exit 0
-------------------------------------------------------------------
(Çé... perlÀº ¿ª½Ã ¾î·Æ±º¿ä... T.T)

(½ÇÇà °á°ú)
# perl uptime2.pl
boot time       : Sat Nov  9 18:49:54 2002
system uptime   :  2hours 25minutes 29seconds
#

-- uptime2.php ------------------------------------------------------
<?php
$stat = file('/proc/stat');                                                                                                                 
$stat[7] = preg_replace('/[^\d]+/','',$stat[7]);                                                                                            

$btime = date('Y.m.d H:i:s',$stat[7]);                                                                                                      
$uptime = runtime(time()-$stat[7]);                                                                                                        

echo <<<_EOF_
boot time\t: $btime<BR>                                                                                                                     
system uptime\t: $uptime<BR>                                                                                                                
_EOF_;

function runtime($term, $lang='kr')
{
  $l[kr] = $l[ko] = array('ÃÊ','ºÐ','½Ã°£','ÀÏ','´Þ');
  $l[en] = array('seconds','minutes','hours','days','mon');
  
  $days  = (int)($term / 86400);
  $secs  = (int)($term % 86400);
  $hours = (int)($secs / 3600); 
  $secs  = (int)($secs % 3600); 
  $mins  = (int)($secs / 60);  
  $secs  = (int)($secs % 60);  
  
  $days = $days ? $days.$l[$lang][3] : '';
  $hours = $hours ? " $hours".$l[$lang][2] : '';
  $mins = $mins ? " $mins".$l[$lang][1].' ' : '';
  $secs .= $l[$lang][0];
  
  return "$days$hours$mins$secs";
}
?>
-------------------------------------------------------------------


[¹æ¹ý5] ±× ¿Ü¿¡ ºÎÆýà »ý¼º/°»½ÅµÇ´Â ·Î±× ÆÄÀÏÀÇ È®ÀÎ

# ls -l --full-time /var/log/dmesg
-rw-r--r--  1 root   root   6867 Sat Nov 09 18:50:17 2002 /var/log/dmesg
#


EOF