Re: CPU load high

On Thu, 23 Aug 2007 12:24:32 +0400, Hannes Dorbath
<light@theendofthetunnel.de> wrote:

> On 23.08.2007 11:04, Max Zorloff wrote:
>> When one postgres process waits for lock to release does it use any cpu?
>> And also, when apache waits for query to finish, does it use cpu?
>
> No, but are you sure what you see is not i/o wait? What values does top
> display in the %wa columns in the CPU rows? What does iostat -dm 1 say
> say under load?
>
>

Well, vmstat 1 says this on 64 users (last column is the same wa) :

procs -----------memory---------- ---swap-- -----io---- --system--
----cpu----
  r  b   swpd   free   buff  cache   si   so    bi    bo   in    cs us sy
id wa
  1  0  12336 289880 331224 3473804    0    4     8   259    1     0 31 13
54  3
13  0  12336 288012 331224 3473872    0    0     0   288 1054  3237 59 17
24  0
  3  0  12336 284044 331224 3473872    0    0     0   480  908  3922 71 18
11  0
  4  0  12336 291500 331224 3473872    0    0     0   248  654  2913 63 13
23  0
  6  0  12336 297220 331224 3473940    0    0     0   240  678  3232 44 12
44  0
  6  0  12336 304312 331224 3473940    0    0     0  1708 1166  3303 50 17
17 16
  9  0  12336 304080 331224 3473940    0    0     0   480  779  4856 61 13
25  0
10  0  12336 309172 331224 3474008    0    0     0   304  697  3094 62 16
21  0
  2  0  12336 308180 331224 3474008    0    0     0   272  681  3370 56 12
32  0
  0  0  12336 307684 331224 3474076    0    0     0   112  689  3212 44 11
44  0
  0  1  12336 312280 331224 3474076    0    0     0  1472  863  3121 51 13
29  7
  7  0  12336 310544 331224 3474076    0    0     0   916 1023  3383 59 14
18  9
  3  0  12336 309428 331224 3474076    0    0     0   224  731  2974 55 14
30  0
  6  0  12336 306444 331224 3474144    0    0     0   392  796  3513 60 14
25  0