Re: High CPU Utilization

Here is vmstat 1 30. We are under peak load right now so I can gather
information from the real deal :)

Had an almost complete lockup a moment ago, number of non-idle
postgres connections was 637. Going to drop our JDBC pool sizes a bit
and bounce everything.

procs -----------memory---------- ---swap-- -----io---- -system-- ----
cpu----
r b swpd free buff cache si so bi bo in cs us sy
id wa
12 35 95056 11102380 56856 14954948 3 4 669 541 1 2
23 3 54 19
12 39 95056 11092484 56876 14963204 0 0 6740 1204 10066
13277 91 5 0 4
8 42 95056 11081712 56888 14972244 0 0 8620 1168 10659 17020
78 6 0 15
10 30 95052 11069768 56904 14982628 0 0 8944 976 9809 15109
81 6 1 12
4 27 95048 11059576 56916 14991296 0 0 8852 440 7652 13294
63 4 2 32
5 42 95048 11052524 56932 14996496 0 0 4700 384 6383 11249
64 4 4 28
5 33 95048 11047492 56956 15001428 0 0 3852 572 6029 14010
36 4 5 56
7 35 95048 11041184 56960 15005480 0 0 3964 136 5042 10802
40 3 1 56
1 33 95048 11037988 56968 15009240 0 0 3892 168 3384 6479
26 1 3 69
3 28 95048 11029332 56980 15015744 0 0 6724 152 4964 12844
11 2 8 79
0 34 95048 11025880 56988 15020168 0 0 3852 160 3616 8614
11 1 6 82
3 25 95048 10996356 57044 15044796 0 0 7892 456 3126 7115
4 3 8 85
1 26 95048 10991692 57052 15050100 0 0 5188 176 2566 5976
3 2 12 83
0 29 95048 10985408 57060 15054968 0 0 4200 80 2586 6582
4 1 12 83
1 29 95048 10980828 57064 15058992 0 0 4560 64 2966 7557
7 2 6 85
2 28 95048 10977192 57072 15063176 0 0 3860 72 2695 6742
11 1 7 81
2 29 95048 10969120 57088 15067808 0 0 5084 84 3296 8067
14 1 0 84
0 25 95048 10962096 57104 15072984 0 0 4440 500 2721 6263
12 1 6 80
0 23 95044 10955320 57108 15079260 0 0 5712 232 2678 5990
6 1 6 87
2 25 95044 10948644 57120 15084524 0 0 5120 184 3499 8143
20 3 9 69
3 21 95044 10939744 57128 15090644 0 0 5756 264 4724 10272
32 3 5 60
1 19 95040 10933196 57144 15095024 12 0 4440 180 2585 5244
13 2 15 70
0 21 95040 10927596 57148 15098684 0 0 3248 136 2973 7292
8 1 9 81
1 20 95040 10920708 57164 15104244 0 0 5192 360 1865 4547
3 1 9 87
1 24 95040 10914552 57172 15105856 0 0 2308 16 1948 4450
6 1 1 93
0 24 95036 10909148 57176 15110240 0 0 3824 152 1330 2632
3 1 6 90
1 21 95036 10900628 57192 15116332 0 0 5680 180 1898 3986
4 1 11 84
0 19 95036 10888356 57200 15121736 0 0 5952 120 2252 3991
12 1 8 79
2 22 95036 10874336 57204 15128252 0 0 6320 112 2831 6755
5 2 8 85
3 26 95036 10857592 57220 15134020 0 0 5124 216 3067 5296
32 6 3 59

Alan, my apologies if you get this twice. Didn't reply back to the
list on first try.

On Mar 16, 2009, at 3:52 PM, Alan Hodgson wrote:

> On Monday 16 March 2009, Joe Uhl <joeuhl(at)gmail(dot)com> wrote:
>> Right now (not under peak load) this server is running at 68% CPU
>> utilization and its SATA raid 10 is doing about 2MB/s writes and
>> 11MB/
>> s reads. When I run dd I can hit 200+MB/s writes and 230+ MB/s
>> reads,
>> so we are barely using the available IO. Further when I run dd the
>> CPU utilization of that process only approaches 20%-30% of one core.
>
> What does vmstat say when it's slow? The output of "vmstat 1 30"
> would be
> informative.
>
> note: dd is sequential I/O. Normal database usage is random I/O.
>
> --
> Even a sixth-grader can figure out that you can’t borrow money to
> pay off
> your debt
>
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