[Samba] 2.2.7a slowness on AIX 5.1-ML03

[William Jojo]

I have an open PMR with IBM regarding a slowness issue when more than 450
smbds are trying to login and download roaming profiles.


The system is a 6H1 with 6 RS64-III 668MHz cpus and 6 GB memory w/Gb
ethernet. We have over 10,000 student accounts with roaming profiles and
800 XP-SP1 workstations for them to choose from.

I've compiled 2.2.7a in 64 bit and 32 bit modes. Run it on both the 32 bit
and 64 bit kernels. IBM has determined that the smbds (from the snap
data) seem to be working until a certain threshold and then can't seem to
get any work done and is unrelated to any resource issues. They have
actually rubber stamped my tunings saying "they're right on the line".

It's so wierd, I thought for sure it must be IBM's problem. But they
insist the system is waiting to service the smbd's if they can just tell
the system what to do.

I'm going to get a log level 10 when this occurs again on Monday as we do
not have sufficient load on Friday (EST).

What I do know is this. We implemented 2.2.5 last semester 32 bit compile
and 32 bit kernel. We've had as many as 650 smbds (equates to active
workstations) without so much as a peep from our students.

Now that we're at 2.2.7a, any one of the possible 4 compile/kernel size
combinations yields the same results. I am using the IBM Visual Age C
compiler version 5.0.2.6.

This symptom is about 40-50% kernel with 40-50% idle. It's as though
something is waiting on an event that can't be seen because of all the
other people waiting to be serviced.

I have no oplocks whatsoever turned on and am using no special features.

Although I do not have complete log information, is there anything you all
could think of that would attribute to this?

I've attached my smb.conf for review.

I know that we were at 2.2.6/7 for a brief period last semester, but
problems with 98 machines and software on samba shares (which i posted
here) caused unresolved illegal operation errors and forced me back to
2.2.5. I still have one DC using 2.2.5 as it serves software to 98 boxes
and they do not like 2.2.6/7/7a at all... :(

I can only assume that some how these are related....

I'm going to gather lots of traces, but I'll need to know who to give them
to.

I'll do the 98 traces and the XP trace against 2.2.7a.


I'm being long winded....I know....


Thanks!

Bill
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# This is the main Samba configuration file. You should read the
# smb.conf(5) manual page in order to understand the options listed
# here. Samba has a huge number of configurable options (perhaps too
# many!) most of which are not shown in this example
#
# Any line which starts with a ; (semi-colon) or a # (hash) 
# is a comment and is ignored. In this example we will use a #
# for commentry and a ; for parts of the config file that you
# may wish to enable
#
# NOTE: Whenever you modify this file you should run the command "testparm"
# to check that you have not many any basic syntactic errors. 
#
#======================= Global Settings =====================================
[global]

# workgroup = NT-Domain-Name or Workgroup-Name, eg: REDHAT4
   workgroup = WINXP

# server string is the equivalent of the NT Description field
#   server string = Samba %v 

# This option is important for security. It allows you to restrict
# connections to machines which are on your local network. The
# following example restricts access to two C class networks and
# the "loopback" interface. For more examples of the syntax see
# the smb.conf man page
   hosts allow = 151.103. 127.

# If you want to automatically load your printer list rather
# than setting them up individually then you'll need this
   load printers = yes

# you may wish to override the location of the printcap file
   printcap name = /etc/printcap

# on SystemV system setting printcap name to lpstat should allow
# you to automatically obtain a printer list from the SystemV spool
# system
;   printcap name = lpstat

# It should not be necessary to specify the print system type unless
# it is non-standard. Currently supported print systems include:
# bsd, sysv, plp, lprng, aix, hpux, qnx
   printing = aix

# Uncomment this if you want a guest account, you must add this to /etc/passwd
# otherwise the user "nobody" is used
;  guest account = pcguest

# this tells Samba to use a separate log file for each machine
# that connects
#   log file = /samba/2.2.6/var/log.%m

# Put a capping on the size of the log files (in Kb).
   max log size = 10000
   log level = 1

# Security mode. Most people will want user level security. See
# security_level.txt for details.
   security = user
#   security = server
#   password server = support
# Use password server option only with security = server
;   password server = <NT-Server-Name>

# You may wish to use password encryption. Please read
# ENCRYPTION.txt, Win95.txt and WinNT.txt in the Samba documentation.
# Do not enable this option unless you have read those documents
  encrypt passwords = yes

# Using the following line enables you to customise your configuration
# on a per machine basis. The %m gets replaced with the netbios name
# of the machine that is connecting
;   include = /usr/local/samba/lib/smb.conf.%m

# Most people will find that this option gives better performance.
# See speed.txt and the manual pages for details
#   socket options = TCP_NODELAY SO_SNDBUF=65536 SO_RCVBUF=65536
#   socket options = TCP_NODELAY IPTOS_LOWDELAY SO_SNDBUF=131072 SO_RCVBUF=131072
   socket options = TCP_NODELAY SO_SNDBUF=131072 SO_RCVBUF=131072

# Configure Samba to use multiple interfaces
# If you have multiple network interfaces then you must list them
# here. See the man page for details.
   interfaces = 151.103.16.156/20

# Browser Control Options:
# set local master to no if you don't want Samba to become a master
# browser on your network. Otherwise the normal election rules apply
   local master = yes

# OS Level determines the precedence of this server in master browser
# elections. The default value should be reasonable
   os level = 60

# Domain Master specifies Samba to be the Domain Master Browser. This
# allows Samba to collate browse lists between subnets. Don't use this
# if you already have a Windows NT domain controller doing this job
   domain master = yes 

# Preferred Master causes Samba to force a local browser election on startup
# and gives it a slightly higher chance of winning the election
   preferred master = yes

# Use only if you have an NT server on your network that has been
# configured at install time to be a primary domain controller.
;   domain controller = <NT-Domain-Controller-SMBName>

# Enable this if you want Samba to be a domain logon server for 
# Windows95 workstations. 
   domain logons = yes

# if you enable domain logons then you may want a per-machine or
# per user logon script
# run a specific logon batch file per workstation (machine)
;   logon script = cet.bat
   logon script = %m.bat
# run a specific logon batch file per username
;   logon script = %U.bat

# Where to store roving profiles (only for Win95 and WinNT)
#        %L substitutes for this servers netbios name, %U is username
#        You must uncomment the [Profiles] share below
;   logon path = \\%L\Profiles\%U

# Windows Internet Name Serving Support Section:
# WINS Support - Tells the NMBD component of Samba to enable it's WINS Server
   wins support = no

# WINS Server - Tells the NMBD components of Samba to be a WINS Client
#	Note: Samba can be either a WINS Server, or a WINS Client, but NOT both
;   wins server = w.x.y.z

# WINS Proxy - Tells Samba to answer name resolution queries on
# behalf of a non WINS capable client, for this to work there must be
# at least one	WINS Server on the network. The default is NO.
;   wins proxy = yes

# DNS Proxy - tells Samba whether or not to try to resolve NetBIOS names
# via DNS nslookups. The built-in default for versions 1.9.17 is yes,
# this has been changed in version 1.9.18 to no.
   dns proxy = no

# HVCC specific settings:
#   domain admin users = root

#   netbios aliases = staff

   oplocks = no
   level2 oplocks = no

;   nt status support = no

#   shared mem size = 4194304
#   write cache size = 2097152

   large readwrite = yes
   kernel oplocks = no
   max open files = 5000
   wide links = no
   lpq command = touch /dev/null
#   ole locking compatibility = yes
   max disk size = 0
   read raw = yes
   write raw = yes
   read size = 65536
   max xmit = 65536
   getwd cache = yes
   time server = true
   logon drive = h:
;   logon path = \\%N\%U\profile
   netbios name = storage
   unix password sync = false
;   passwd program = /usr/bin/passwd %u
;   passwd chat = "*password:*" %o\n "*password:*" %n\n "*password:*" %n\n "*NIS passwd changed*"
   deadtime = 0
   short preserve case = no

#============================ Share Definitions ==============================
[homes]
   comment = Home Directories
   browseable = no
   writeable = yes
   path = %H
   locking = yes
#   oplocks = yes
   guest ok = no
#   level2 oplocks = yes
   write cache size = 262144
#   write cache size = 2097152
   force create mode = 0644
   force directory mode = 0755

# Un-comment the following and create the netlogon directory for Domain Logons
[netlogon]
  comment = Network Logon Service
  path = /netlogon
  guest ok = no
  writeable = no
  browseable = no
#   valid users = @web @ops @staff @system billtest tr100655 robotest
  root preexec = echo User %U-%u LOGGED IN %M-%m-%I via %h-%S at %T >>/etc/%L.log
  root postexec = echo User %U-%u LOGGED OUT %M-%m-%I via %h-%S at %T >>/etc/%L.log


[forms]
  comment = Banner Forms Share
  path = /forms
  writeable = no
  guest ok = no
  browseable = no

[common]
  comment = common area
  path = /common
  writeable = yes
  guest ok = no
  browseable = no
#  root preexec = /usr/local/bin/notice.ksh %m &
  root preexec = /usr/local/bin/smbquota.ksh %U %m &
#  root preexec = /usr/local/bin/writelog %U %m LOGIN &
#  root postexec = /usr/local/bin/writelog %U %m LOGOUT &
#   valid users = @web @ops @staff @system billtest tr100655 robotest
  admin users = billtest

[toplevel]
  comment = Production Share
  path = /staff
  writeable = yes
  guest ok = yes
  valid users = @staff billtest glaudsuz
  browseable = no

# NOTE: If you have a BSD-style print system there is no need to 
# specifically define each individual printer
[printers]
   comment = All Printers
   path = /var/spool/samba
   browseable = no
# Set public = yes to allow user 'guest account' to print
   guest ok = no
   writeable = no
   printable = yes

# The following two entries demonstrate how to share a directory so that two
# users can place files there that will be owned by the specific users. In this
# setup, the directory should be writable by both users and should have the
# sticky bit set on it to prevent abuse. Obviously this could be extended to
# as many users as required.
;[myshare]
;   comment = Mary's and Fred's stuff
;   path = /usr/somewhere/shared
;   valid users = mary fred
;   public = no
;   writable = yes
;   printable = no
;   create mask = 0765