[Samba] strange performance some times

[kazabe]

Hi

I have a samba server (3.4.3-2 lenny version).  This server is a PDC
with roaming profiles.

was migrated from an old woody server.

Some times, all the users report me low performance when run an app
shared on a public folder.  The app is an access database.   Some
times work very fast, some times work very slow.

how can i detect the reason of the low performance?   the cpu, memory
process and swap usage is always minimal.  Never show heavy process.

This is a virtualized server (i use Xen).  The virtualization can
affect the samba performance?  the virtual server has four times more
resources than the old server.



thanks and regards.

This is my smb.conf

PDC:# cat /etc/samba/smb.conf
[global]
	netbios name = PDC
	netbios aliases = SRV
	ldap ssl = no
	passwd chat debug = yes
	name resolve order = wins bcast hosts
	idmap gid = 15000-20000
	passwd chat = *Enter\snew\sUNIX\spassword:* %n\n
*Retype\snew\sUNIX\spassword:* %n\n *password\supdated\ssuccessfully*
.
	veto files = *.mpg
	passwd program = /usr/bin/passwd %u
	use client driver = Yes
	dns proxy = No
	printing = cups
	idmap uid = 17000-30000
	logon script = logon.bat
	local master = yes
	workgroup = COMPANY
	os level = 99
	printcap name = /etc/printcap
	security = user
	add machine script = /usr/sbin/useradd -s /bin/false/ -d /var/lib/nobody %u
	getwd cache = yes
	delete user script = /usr/sbin/userdel -r %u
	max log size = 1000
	log level = 3
	log file = /var/log/samba/log.%m
	read raw = yes
	add group script = /usr/sbin/groupadd %g
	smb ports = 139 445
	delete group script = /usr/sbin/groupdel %g
	socket options = SO_KEEPALIVE IPTOS_LOWDELAY TCP_NODELAY
SO_SNDBUF=8192 SO_RCVBUF=8192
	add user to group script = /usr/sbin/usernod -G %g %u
	logon drive = P:
	domain master = yes
	username map = /etc/samba/smbusers
	interfaces = eth0 192.168.2.1
	encrypt passwords = yes
	passdb backend = tdbsam
	logon home = \\pdc\%U
	template shell = /bin/false
	wins support = yes
	server string = PDC Server
	enhanced browsing = yes
	unix password sync = yes
	logon path = \\pdc\profiles\%U
	add user script = /usr/sbin/useradd -m %u -g users -G users
	hide special files = Yes
	utmp = Yes
	preferred master = true
	domain logons = yes

	admin users = @sysadmin



[netlogon]
	comment = Samba Network Logon Service
	path = /home/share/netlogon
	case sensitive = no
	guest ok = yes
	locking = no
	writable = no
	public = no
	browseable = yes

[%U]
	comment = %u Home
	read only = no
	create mask = 0660
	directory mask = 0770
	browseable = no
	path = /home/%U/Archivos

[main]
	comment = main shared
	path = /opt/pdc/main
	read only = no
	force group = users
	valid users = @users
	create mask = 0660
	directory mask = 0770
	hide files = /data/templates/
	oplocks = yes



[public]
	comment = Public Dir
	path = /opt/pdc/pub
	read only = no
	force group = users
	valid users = @users
	create mask = 0666
	directory mask = 0777
	writable = yes

[profiles]
	path        = /opt/pdc/profiles
	writeable   = yes
	create mask = 0700
	directory mask = 0700
	;browseable   = no
	guest ok    = no