Extremely high CPU usage when building tables - Mailing list pgsql-performance

From Deborah Fuentes
Subject Extremely high CPU usage when building tables
Date
Msg-id 306A7ABFF569E847BC99BA08C183EFF3ED95@WINEX1.eldocomp.com
Whole thread Raw
Responses Re: Extremely high CPU usage when building tables
List pgsql-performance
Hello,

When I run an SQL to create new tables and indexes is when Postgres consumes all CPU and impacts other users on the
server.

We are running Postgres 8.3.7 on a Sun M5000 with 2 x quad core CPUs (16 threads) running Solaris 10.

I've attached the sar data at the time of the run- here's a snip-it below.

Any ideas would be greatly appreciated.

Thanks!
Deb

****************************************************

Here, note the run queue, the left column. That is the number of processes waiting to run. 97 processes waiting to run
atany time with only eight CPU cores looks very busy.  

root@core2 # sar -q 5 500

SunOS core2 5.10 Generic_142900-11 sun4u    06/17/2010

12:01:50 runq-sz %runocc swpq-sz %swpocc
12:01:55     1.8      80     0.0       0
12:02:00     1.0      20     0.0       0
12:02:05     1.0      20     0.0       0
12:02:10     0.0       0     0.0       0
12:02:15     0.0       0     0.0       0
12:02:21     3.3      50     0.0       0
12:02:26     1.0      20     0.0       0
12:02:31     1.0      60     0.0       0
12:02:36     1.0      20     0.0       0
12:02:42    27.0      50     0.0       0
12:02:49    32.8      83     0.0       0
12:02:55    76.0     100     0.0       0
12:03:01    66.1     100     0.0       0
12:03:07    43.8     100     0.0       0
12:03:13    52.0     100     0.0       0
12:03:19    91.2     100     0.0       0
12:03:26    97.8      83     0.0       0
12:03:33    63.7     100     0.0       0
12:03:39    67.4     100     0.0       0
12:03:47    41.5     100     0.0       0
12:03:53    82.0      83     0.0       0
12:03:59    88.7     100     0.0       0
12:04:06    87.7      50     0.0       0
12:04:12    41.3     100     0.0       0
12:04:17    94.3      50     0.0       0
12:04:22     1.0      20     0.0       0
12:04:27     3.3      60     0.0       0
12:04:32     1.0      20     0.0       0
12:04:38     0.0       0     0.0       0


pgsql-performance by date:

Previous
From: Greg Smith
Date:
Subject: Re: PostgreSQL as a local in-memory cache
Next
From: Rajesh Kumar Mallah
Date:
Subject: how to (temporarily) disable/minimize benefits of disk block cache or postgresql shared buffer