Mysql Problem: all query become slow for some sec...

[kamyweb]

Hi, I have a problem on our primary db server.
This server manage the portal db, forums, other sites and a real time application (mmoprg server).
Our db server is a dual xeon 2.8Ghz with 2GB ram, SCSI disks with mysql 5.0.32 (on gentoo system).
Every 10-20 minutes all db server stop for some seconds and I can't understand why... the stop appear also on MySql Administration Console and produce some slow query as u can see on this images http://img301.imageshack.us/my.php?image=mysqladmin2ff3.jpg http://img405.imageshack.us/my.php?image=mysqladminwu1.jpg

make.conf
CFLAGS="-O2 -march=pentium4 -pipe -fomit-frame-pointer"
CXXFLAGS="${CFLAGS}"
CHOST="i686-pc-linux-gnu"
MAKEOPTS="-j5"

cpuinfo
vendor_id : GenuineIntel
cpu family : 15
model : 2
model name : Intel(R) Xeon(TM) CPU 2.80GHz
stepping : 9
cpu MHz : 2791.352
cache size : 512 KB
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe cid xtpr
bogomips : 5591.75

emerge -pv mysql (~x86)
[ebuild R ] dev-db/mysql-5.0.32 USE="berkdb latin1 max-idx-128 perl ssl -big-tables -cluster -debug -embedded -extraengine -minimal (-selinux) -static"

my.cnf
basedir = /usr
datadir = /db
skip-locking
key_buffer = 384M
max_allowed_packet = 2M
table_cache = 4000
sort_buffer_size = 32M
net_buffer_length = 32K
read_buffer_size = 2M
read_rnd_buffer_size = 3M
tmp_table_size = 64M
myisam_sort_buffer_size = 32M
thread_concurrency = 8
thread_cache_size = 16
max_connections = 600
max_user_connections = 600
query_alloc_block_size = 8192
query_cache_limit = 1M
query_cache_min_res_unit = 4096
query_cache_type = 1
query_cache_size = 256M
log_slow_queries = /var/log/mysql/mysqld.slow.log
language = /usr/share/mysql/english
bind-address = 0.0.0.0
server-id = 1
tmpdir = /tmp/
innodb_buffer_pool_size = 16M
innodb_additional_mem_pool_size = 2M
innodb_data_file_path = ibdata1:10M:autoextend:max:128M
innodb_log_file_size = 5M
innodb_log_buffer_size = 8M
set-variable = innodb_log_files_in_group=2
innodb_flush_log_at_trx_commit = 1
innodb_lock_wait_timeout = 50

System memory usage:
Mem: 2075084k total, 1676528k used, 398556k free, 0k buffers
Swap: 987988k total, 2476k used, 985512k free, 1228080k cached

System processor usage:
Tasks: 63 total, 2 running, 61 sleeping, 0 stopped, 0 zombie
Cpu0 : 3.9% us, 5.9% sy, 1.0% ni, 89.2% id, 0.0% wa, 0.0% hi, 0.0% si
Cpu1 : 1.0% us, 5.0% sy, 17.0% ni, 77.0% id, 0.0% wa, 0.0% hi, 0.0% si
Cpu2 : 0.0% us, 1.0% sy, 7.0% ni, 92.0% id, 0.0% wa, 0.0% hi, 0.0% si
Cpu3 : 0.0% us, 7.1% sy, 60.6% ni, 32.3% id, 0.0% wa, 0.0% hi, 0.0% si

Some DB Stats:
Traffic per hour
Received 86 MB
Sent 165 MB
Total 250 MB

Connections
max. concurrent connections 234
Failed attempts 0
Aborted 362
Total 11 k
Query statistics: Since its startup, 912,949 queries have been sent to the server.
Total 913 k
ø per hour 504.93 k
ø per minute 8.42 k
ø per second 140.26


I need an help to remove that "lag" problem or some suggestion where can research the problem....

Verty Thx 4 any help
Luca Camillo