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RE: OT : kernel using 75% of CPU

From: Christopher Spence <cspence_at_FuelSpot.com>
Date: Tue, 28 Aug 2001 13:01:31 -0700
Message-ID: <F001.0037A5F6.20010828132411@fatcity.com>

That
depends on the OS. 
 
There
is no simple answer, but basically if your using an OS like solaris which I believe you mentioned, then Pi/Po is swaping, paging, as well as file io.
Your
best bet is looking at the SR (scan rate), but if you enable priority paging, the scan rate will be higher than normal (below 20 or so). <SPAN
class=753411420-28082001> 
I like
to use the DE column, forget what it stands for, but it basically means how much memory the system thinks it is lacking at that instance.  Used with the SR, Pi, Po, I can ussually get a good grasp of if there is a memory problem.  Also the monitor the page faults. <SPAN
class=753411420-28082001> 
I
would almost always completely ignore free column, you will almost always be 1-10% free depending on your kernel parameters.  If
your OS does not use the paging process to handle file buffering, then SR is your best measure of how aggressively the box is trying to find memory.
<SPAN
class=753411420-28082001> 
"Do not criticize someone until you walked a mile in their shoes, that way when you criticize them, you are a mile a way and have their shoes."
Christopher R. Spence <FONT

face="Comic Sans MS" size=2>Oracle DBA <FONT face="Comic Sans MS" 
size=2>Phone: (978) 322-5744 <FONT face="Comic Sans MS" 
size=2>Fax:    (707) 885-2275 

Fuelspot <FONT
face="Comic Sans MS" size=2>73 Princeton Street <FONT 
face="Comic Sans MS" size=2>North, Chelmsford 01863 <FONT 
face="Comic Sans MS" size=2>  

  

  <FONT
  face=Tahoma size=2>-----Original Message-----From: Jerry C   [mailto:usidba_at_yahoo.com] Sent: Tuesday, August 28, 2001 4:01   PMTo: Multiple recipients of list ORACLE-LSubject: Re:   OT : kernel using 75% of CPU
  Thanks for the reply, Chris.
 

  I'm a bit ashamed, being as old as I am,   that I don't have a better grasp on swapping. I initially thought maybe it was   a swap problem also, but top shows 0.0% swap. I thought I had also checked   vmstat earlier, but yikes:
 

  csuaor46> csuaor46> vmstat 15

  20 procs     
  memory            
  page            
  disk          
  faults      cpu r b w   swap  
  free  re  mf pi po fr de sr s6 s1 s1 s5   in   
  sy   cs us sy id 2 0 0  15352 14472  68 1513 14   227 953 56488 260 0 2 2 0 638 78  933 25 24 50 11 0 0 6240696   63336 105 1759 41 246 1754 62760 545 0 8 8 0 1130 4956 773 22 76 1 11   0 0 6243360 62864 42 2594 82 236 2357 62760 757 0 7 6 0 1239 6960 987 40 60   1 8 0 0 6238120 62368 48 1746 25 260 3767 56488 1198 0 7 6 0 1052   4837 762 36 63 1 8 0 0 6239640 65200 33 1772 229 262 2092 62760 619 0   16 16 0 1232 5776 871 28 70 2 5 1 0 6247656 62440 57 2078 162 497   4025 62760 1308 0 15 15 0 1216 5808 815 21 75 4 5 0 0 6247776 63456   26 2445 149 285 2716 62760 2188 0 11 13 0 1164 6593 903 17 79 4 10 1   0 6240680 62648 80 3008 266 523 4527 62760 9226 0 25 25 0 1127 6725 884 22 76   2 6 0 0 6218216 68664 33 2251 66 105 1086 62760 377 0 6 6 0 847 20782   744 31 67 2 5 0 0 6201240 62840  9 1799 72 350 2490 62760 415 0   9 9 0 1207 8889 781 15 80 5 5 0 0 6199336 62760  6 1935 40 923   3564 62760 636 0 9 9 0 1373 5193 1082 21 69 10 10 0 0 6189552 63840   11 1476 33 722 3089 62760 548 0 9 8 0 1364 4530 957 21 77 2 10 0 0   6174304 70704 25 2705 86 759 6441 62760 1003 0 10 10 0 1258 5551 836 29 67   4 8 0 0 6186512 63824 51 1728 44 227 1413 56488 188 0 9 7 0 1319 4485   676 31 68 0 7 0 0 6196448 63064 49 1635 44 235 1179 62760 167 0 4 4 0   1207 4968 694 39 61 1 9 0 0 6188656 63872 11 1915 112 433 2065 62760   308 0 13 12 0 1140 4835 828 37 62 1
 

  Do the pi (page in) and po (page out)   statistics represent swapping?!
 
 

  Thanks again,
 

  Jerry
  <BLOCKQUOTE dir=ltr
  style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">

    Sent: Tuesday, August 28, 2001 1:30     PM
    Subject: RE: OT : kernel using 75% of     CPU          <FONT face=Arial color=#0000ff
    size=2>paging and swapping is the first thing that comes to mind, look at     vmstat.
     
    I
    think your question is completely on topic.      
    "Do not criticize someone until you walked a     mile in their shoes, that way when you criticize them, you are a mile a way     and have their shoes."
    Christopher R. Spence <FONT

    face="Comic Sans MS" size=2>Oracle DBA <FONT face="Comic Sans MS" 
    size=2>Phone: (978) 322-5744 <FONT face="Comic Sans MS" 
    size=2>Fax:    (707) 885-2275 

    Fuelspot <FONT
    face="Comic Sans MS" size=2>73 Princeton Street <FONT 
    face="Comic Sans MS" size=2>North, Chelmsford 01863 <FONT 
    face="Comic Sans MS" size=2>  
    
      
      <FONT 
      face=Tahoma size=2>-----Original Message-----From: Jerry C 
      [mailto:usidba_at_yahoo.com] Sent: Tuesday, August 28, 2001 11:20 
      AMTo: Multiple recipients of list ORACLE-LSubject: 
      OT : kernel using 75% of CPU
      Hi there,
       
      I have a Sun e4500, running Solaris 
      2.7 and Oracle 8.1.7.1.0. Everything looks normal from a database 
      perspective, but when I run "top" it show the kernel being very 
      hog-like:
       
      load averages: 14.38, 15.18, 
      15.18                                     
      07:16:21126 processes: 118 sleeping, 4 running, 4 on cpuCPU 
      states:  0.6% idle, 26.6% user, 72.8% kernel,  0.0% 
      iowait,  0.0% swapMemory: 4096M real, 63M free, 216M swap in use, 
      5310M swap free
       
        PID USERNAME THR PRI 
      NICE  SIZE   RES STATE   TIME    
      CPU COMMAND 2286 oracle     1   
      0    0 1844M 1814M run     9:44 13.90% 
      oracle11068 oracle     1   
      0    0 2056K 1536K cpu0    0:02  1.53% 
      top11333 oracle     1   
      0    0 1150M 1124M cpu1    0:01  1.39% 
      oracle 5944 oracle     1  
      40    0 1820M 1789M sleep  14:40  1.36% 
      oracle 4797 root       1  
      50    0 2112K 1248K sleep   6:01  1.36% 
      top11346 oracle     1   
      0    0  110M   92M cpu0    
      0:01  1.26% oracle11114 oracle     
      1   0    0 1009M  984M 
      cpu1    0:00  0.66% oracle11157 
      oracle     1   0    0 
      1009M  984M run     0:00  0.63% 
      oracle11368 oracle     1  
      33    0 1794M 1765M sleep   0:00  0.29% 
      oracle19558 oracle     1  
      60    0 1797M 1751M sleep  78:28  0.28% 
      oracle19554 oracle     1  
      60    0 1794M 1751M sleep  38:05  0.20% 
      oracle11366 oracle     1  
      55    0 1793M 1763M sleep   0:00  0.19% 
      oracle11292 oracle     1  
      26    2 2008K 1424K run     0:00  
      0.19% dsql
       
      Any ideas on what I, as a lowly DBA, 
      would be able to check? It's a bit out of my area and I'm 
      stumped...
       
       
      Thanks!
       
      <FONT face="Courier New" 

  size=2>Jerry Received on Tue Aug 28 2001 - 15:01:31 CDT

Original text of this message

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