[Samba] Samba + Clipper too slow

[Jose Carlos Estrada Jimenez]

Hi everybody!

We've a legacy application based on Clipper, very important
for the company. 
And we want to share the database and program files through
a samba server with Gentoo Linux.
But, when the users mapping the resource with a Windows 98, 2K
or XP client, the application run VERY VERY slow.
This application has been shared with Windows 98, 2K or XP
and run too much faster than Samba.
We tried tuning the smb.conf modifying parameters:
oplock, lock spin time, etc...
We have read the documentation about SAMBA in:
http://www.oreilly.com/catalog/samba/chapter/book/appb_02.html
http://www.drouillard.ca/Tips&Tricks/Samba/Oplocks.htm

We've tried with different schemas:
Filesystems: ext3, reiserfs, xfs, vfat with and without LVM2

and tried again, but with the same result: the application run
VERY slow.

Any clues on what could be the problem? and how to solve them?

Beforehand thanks!

The hardware in the server is:
Processor Intel Pentium 4 HT @ 2.80GHz
RAM 512MB DDR
HDD 80GB SATA
NIC Broadcom NetXtreme BCM5751 Gigabit Ethernet

samba version: 3.0.10
Gentoo version: 2005.0
kernel version: 2.6.11

and the last smb.conf version:

# Global Settings ==============================================================
[global]

  # Server Naming Options
  workgroup = WORLD
  netbios name = myserver
  server string = This is my Server in Linux %v

  # Messaging Options
  # message command = sh -c '/usr/local/bin/wmpopup samba %s %f;rm %s' &
  # message command = echo "%f %m %s" |/usr/bin/smbclient -M anymachine
  # message command = cat %s |/usr/bin/smbclient -M anymachine
  # preexec = echo "Welcome %u to MyServer" |/usr/bin/smbclient -M %m
        
  # Logging Options
  log file = /var/log/samba/%m.log
  max log size = 50
  log level = 1

  # Performance Options
  getwd cache = yes
  use sendfile = no
  # lock spin time = 15
  # lock spin time = 30 # Netperf - 5s
  # lock spin time = 45 # Netperf - 4s
  # lock spin time = 60 # Netperf - 4s
  lock spin time = 45
  lock spin count = 10
  dos filetimes = yes
  oplocks = no
  level2 oplocks = no
  change notify timeout = 300
  lpq cache time = 30
  # max xmit = 32768 # more than 5:55
  # read raw = yes
  # write raw = yes
  # max xmit = 65535
  # dead time = 60
  # shared mem size = 6291456 # No se reconoce
  # read prediction = no # No se reconoce
                
  # Security and Domain Membership Options
  security = user
  encrypt passwords = yes
  smb passwd file = /etc/samba/smbpasswd
  #hosts allow = 192.168.1.0/255.255.255.0

  # Networking Options
  interfaces = eth0 lo
  bind interfaces only = yes
  socket options = TCP_NODELAY SO_SNDBUF=65536 SO_RCVBUF=65536 IPTOS_LOWDELAY
                                    
  # Browser Option
  domain master = no
  preferred master = no
  os level = 64
  local master = no
  remote browse sync = 192.168.1.255
  dns proxy = no
  wins proxy = no
  wins server = 192.168.1.10
  name resolve order = lmhosts hosts wins bcast
                                                  
  # Administration Options
  admin users = admin
  map to guest = bad user
  
# Share Definitions ==========================================================
[homes]
  comment = Home Directories
  browseable = no
  writable = yes
  create mask = 0644
  directory mask = 0775
            
# [netlogon]
  #  comment = Network Logon Service
  #  path = /var/lib/samba/netlogon
  #  guest ok = yes
  #  writable = no
            
# [Profiles]
  #  path = /var/lib/samba/profiles
  #  browseable = no
  #  guest ok = yes
            
[MyClipperApp]
  comment = The Clipper App
  path = /home/clipper
  writable = yes
  browseable = yes
                        
  # Security
  valid users = clipper @users
  write list = clipper @users
  admin users = clipadm
  create mask = 0664
  directory mask = 0775
  delete readonly = yes
  force user = clipper
  force group = users
  
  # Tuning
  oplocks = no
  level2 oplocks = no