Overusing 1 CPU

From: Mozzi <mozzi(dot)glug(at)gmail(dot)com>
To: pgsql-performance(at)postgresql(dot)org
Subject: Overusing 1 CPU
Date: 2010-06-02 11:12:40
Message-ID: 1275477160.1818.48.camel@stefaans-laptop
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Hallo all

I have a strange problem here.
I have a pgsql database running on Intel hardware here, it has 8 cores
hyperthreaded so you see 16 cpu's.

This box is basically adle @ the moment as it is still in testing yet
top shows high usage on just 1 of the cores.
mpstat gives the below.
As you can see only cpu 1 is verey bussy, the rest are idle.

Thanx

Mozzi

13:02:19 CPU %usr %nice %sys %iowait %irq %soft %steal
%guest %idle
13:02:21 all 4.70 0.00 0.41 1.57 0.00 0.00 0.00
0.00 93.32
13:02:21 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 100.00
13:02:21 1 72.68 0.00 5.37 21.46 0.00 0.49 0.00
0.00 0.00
13:02:21 2 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 100.00
13:02:21 3 0.00 0.00 0.51 0.00 0.00 0.00 0.00
0.00 99.49
13:02:21 4 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 100.00
13:02:21 5 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 100.00
13:02:21 6 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 100.00
13:02:21 7 0.00 0.00 0.36 0.00 0.00 0.00 0.00
0.00 99.64
13:02:21 8 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 100.00
13:02:21 9 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 100.00
13:02:21 10 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 100.00
13:02:21 11 0.00 0.00 0.00 1.00 0.00 0.00 0.00
0.00 99.00
13:02:21 12 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 100.00
13:02:21 13 0.00 0.00 0.00 2.00 0.00 0.00 0.00
0.00 98.00
13:02:21 14 0.00 0.00 0.51 0.00 0.00 0.00 0.00
0.00 99.49
13:02:21 15 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 100.00

Average: CPU %usr %nice %sys %iowait %irq %soft %steal
%guest %idle
Average: all 4.66 0.00 0.43 1.46 0.00 0.04 0.00
0.00 93.41
Average: 0 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 100.00
Average: 1 72.27 0.00 5.47 21.58 0.00 0.59 0.00
0.00 0.10
Average: 2 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 100.00
Average: 3 0.10 0.00 0.50 0.00 0.00 0.00 0.00
0.00 99.40
Average: 4 0.10 0.00 0.10 0.00 0.00 0.00 0.00
0.00 99.80
Average: 5 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 100.00
Average: 6 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 100.00
Average: 7 0.00 0.00 0.10 0.60 0.00 0.00 0.00
0.00 99.30
Average: 8 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 100.00
Average: 9 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 100.00
Average: 10 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 100.00
Average: 11 0.00 0.00 0.00 0.20 0.00 0.00 0.00
0.00 99.80
Average: 12 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 100.00
Average: 13 0.00 0.00 0.10 0.40 0.00 0.00 0.00
0.00 99.50
Average: 14 0.00 0.00 0.50 0.00 0.00 0.00 0.00
0.00 99.50
Average: 15 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0.00 100.00

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