Mysql running slow on Mandrake Linux 10.0 for AMD 64

[Scott]

Hi,

I'm having a problem with a new machine running Mysql version 4.0.18
on the AMD64 version of Mandrake 10.0. The new machine has got 64bit
AMD processor and 2GB of RAM.

Nearly all queries(updates are especially slow) are running 20/30 or
more times slower than on an inferior(32 bit processor, 1.5GB RAM)
machine runnning Mysql 3.23.56 on mandrake 9.0.

As far as I can tell mysql is configured correctly for the power of
the machine.
The my.cnf file looks like this:

# This is for large system with memory of 1G-2G where the system runs
mainly
# MySQL.
#
# You can copy this file to
# /etc/my.cnf to set global options,
# mysql-data-dir/my.cnf to set server-specific options (in this
# installation this directory is /var/lib/mysql) or
# ~/.my.cnf to set user-specific options.
#
# One can in this file use all long options that the program supports.
# If you want to know which options a program support, run the program
# with --help option.

# The following options will be passed to all MySQL clients
[client]
#password = your_password
port = 3306
socket = /var/lib/mysql/mysql.sock

# Here follows entries for some specific programs

# The MySQL server
[mysqld]
#turn off ability to use InnoDB tables
skip-innodb
port = 3306
socket = /var/lib/mysql/mysql.sock
skip-locking
key_buffer = 384M
max_allowed_pac ket = 1M
table_cache = 512
sort_buffer_siz e = 2M
read_buffer_siz e = 2M
read_rnd_buffer _size = 2M
myisam_sort_buf fer_size = 64M
thread_cache = 8
query_cache_siz e = 32M
tmp_table_size = 64M
# Try number of CPU's*2 for thread_concurre ncy
thread_concurre ncy = 8
# Replication Master Server (default)
# binary logging is required for replication
log-bin

# required unique id between 1 and 2^32 - 1
# defaults to 1 if master-host is not set
# but will not function as a master if omitted
server-id = 1
# Point the following paths to different dedicated disks
#tmpdir = /tmp/
tmpdir=/home/mysqltemp
#log-update = /path-to-dedicated-directory/hostname

# Uncomment the following if you are using BDB tables
#bdb_cache_size = 384M
#bdb_max_lock = 100000

# Uncomment the following if you are using InnoDB tables
#innodb_data_ho me_dir = /var/lib/mysql/
#innodb_data_fi le_path = ibdata1:2000M;i bdata2:10M:auto extend
#innodb_log_gro up_home_dir = /var/lib/mysql/
#innodb_log_arc h_dir = /var/lib/mysql/
# You can set .._buffer_pool_ size up to 50 - 80 %
# of RAM but beware of setting memory usage too high
#innodb_buffer_ pool_size = 384M
#innodb_additio nal_mem_pool_si ze = 20M
# Set .._log_file_siz e to 25 % of buffer pool size
#innodb_log_fil e_size = 100M
#innodb_log_buf fer_size = 8M
#innodb_flush_l og_at_trx_commi t = 1
#innodb_lock_wa it_timeout = 50

[mysqldump]
quick
max_allowed_pac ket = 16M

[mysql]
no-auto-rehash
# Remove the next comment character if you are not familiar with SQL
#safe-updates

[isamchk]
key_buffer = 256M
sort_buffer_siz e = 256M
read_buffer = 2M
write_buffer = 2M

[myisamchk]
key_buffer = 256M
sort_buffer_siz e = 256M
read_buffer = 2M
write_buffer = 2M

[mysqlhotcopy]
interactive-timeout
Does anyone know any reason why the new machine is so rubbish??

Thanks in advance
Scott