[CentOS] CentOS5 running very slowly on a core 2 duo with 4 GB RAM

[John R Pierce]

israel.garcia at cimex.com.cu wrote:
>
> Hi, I’ve installed CentOS5.2 on an INTEL Core 2 Duo (Intel(R) 
> Core(TM)2 Duo CPU E6550 @ 2.33GHz), 4 GB RAM (MemTotal: 4072176 kB) 
> and my system gets sevarel minutes to startup, specially on udev 
> daemon. Once the system is UP, every command I run gets 100% CPU and 
> every is very slowly at the point yum –y update never ends. The system 
> installed by default this kernel 2.6.18-53.el5PAE. I would like to 
> know what’s wrong with my server. Do I have to install another kernel? 
> Can you help me?
>
> More details of my server:
>

additional useful info might be ...

# dmesg
# lspci
#vmstat 5 5
# iostat -x 5 5

the last 2 will take about 30 seconds each to run (oh, iostat is part of 
package `sysstat` which may not be installed by default, `yum install 
sysstat`)

and if the dmesg output doesn't start with
Linux version 2.6.18-92.1.6.el5 (mockbuild at builder16.centos.org) (gcc 
version 4.1.2 20071124 (Red Hat 4.1.2-42)) #1 SMP Wed Jun 25 1
3:49:24 EDT 2008

(or similar) that means the dmesg buffer likely overflowed, so cat 
/var/log/dmesg to get the snapshot output of it right after the system 
booted