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Date:      Wed, 5 Nov 1997 12:11:32 -0800
From:      Joe McGuckin <joe@via.net>
To:        hackers@freebsd.org
Subject:   'sys' is consuming %50 of cpu
Message-ID:  <199711052011.MAA27359@monk.via.net>

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I've got a web server that was just upgraded to a 300Mhz Pentium II.

Now the load average is down to a more manageable '20'.

This machine has around 3K tcp connections to it according to netstat.
Here they are listed by type:

CLOSE_WAIT                5
LAST_ACK                 25
ESTABLISHED             443
SYN_RCVD                 59
FIN_WAIT_1              341
LISTEN                    1
TIME_WAIT               723
FIN_WAIT_2             1716
CLOSING                  29

One thing I've noticed is that vmstat reports that the kernel
is using over 50% of the cpu:

 procs   memory     page                    disks   faults      cpu
 r b w   avm   fre  flt  re  pi  po  fr  sr s0 s1   in   sy  cs us sy id
63 1 0469488 46096  303   0   0   0 260 110  3 46 1339 4284 2445 16 54 30
31 1 0470192 45084  370   0   0   0 253   0  0 23 1572 5277 3150 13 87  0
60 1 0469216 43668  530   0   0   0 380   0  2 32 1574 5162 2172 17 83  0
50 7 0468076 41548  465   0   0   0 348   0 12 73 1561 5172 2203 15 85  0
5535 0472800 39856  384   0   0   0 203   0  0 163 1588 4749 1836 13 87  0
7511 0476216 38988  776   0   0   0 514   0  0 96 1595 5835 2150 24 74  2
 5 1 0479988 39852  596   0   0   0 598   0  0 33 1731 6267 3114 20 80  0

----------------------------------------------------------------------------------

    2 users    Load 18.18 12.81 13.37                  Wed Nov  5 11:53
 
Mem:KB 3112    1108   464516     1316   41264         VN PAGER  SWAP PAGER
      54716    1976  3927692     8464    Free         in  out     in  out
Act  111568    1108   466136     1316   49780 count    86
All  247736    1980  3942260     8556         pages   163         358
    75     3420      3024  485 5417 1359  198  346  59600 cow    Interrupts
Proc:r  p  d  s  w    Csw  Trp  Sys  Int  Sof  Flt  49884 zfod   1336 total
64.5%Sys  17.3%Intr 16.44  509 4984 1336 1.99  374  59180 wire    092 clk0 irq0
                                                   139168 act      38 rtc0 irq8
68.0%Sys  16.4%Intr 14.=========+++++++++>>>>>>>     2096 inact  1082 pci irq10
|    |    |    |    |    |    |    |    |    |      40704 cache    26 pci irq11
==================================++++++++>>>>>>     9245 free        fdc0 irq6
                                                          daefr       sc0 irq1
    20669    14385   70       35    0                 213 prcfr
    Calls     hits    %     hits    %                     react
    16645    12251   74       32    0                     pdwake
             38                                         1 pdpgs
Discs  sd    38                                           intrn
seeks    1  254                                      8345 buf
xfers        26
 blks    1  193
 msps

------------------------------------------------------------------------------------

Is there anything I can do to reduce the amount of cpu the kernel is using?
With this many network connections, would I gain anything by making the TCBHASHSIZE
larger?

What about turning off FAILSAFE? Would that make a noticable difference?

Also, the ethernet card I'm using is a 100mb 3COM (VX driver). I notice that
the man page for the vx driver implies that this card is a poor performer.
Is that still true? What card should I get?

Thanks!

Joe



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