On Thu, 23 Aug 2007 12:24:32 +0400, Hannes Dorbath
<light@xxxxxxxxxxxxxxxxxxxx> 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
---------------------------(end of broadcast)---------------------------
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