[Samba] Degraded performance using a Linux to Windows Samba/CIFS share

[Wagner, Brian]

We have been having some performance issues that come and go with our Samba share.  At the bottom you will see the smb.conf(I have removed all extra information)

Summary:

We have a windows share that we access via windows and a couple Linux servers.  The place we are seeing the most pain, probably because it is where the most IO happens is from the Linux servers.  The main thing the Linux servers are doing, are scanning the file system for files and checking to see what needs to process next (file monitor).  These scans will go from taking seconds to hours when we see the issues.  Please note these shares are comprised of both a lot of directories and a lot of files.  Most of the directories are small and only have a few files, but there are some large directories, and especially when we get behind there are even more with a lot of files.  When we have noticed this slowdown we have involved our systems, storage, networking, and application teams, and no one is able to put their thumb on what is causing it.  We have noticed that restarting the Linux(client) servers at least temporarily resolves the slowness and things speed up for a time.  The majority of the time we are processing without incident but have more frequently been getting been getting into this state.  There is more data being added to this, but no recent large jumps.  We have been running this same architecture for many years now.

It seems that there is either some locking, or caching that is happening that is causing it to drag to halt.  Not all clients go bad at the same time, but it seems that eventually when we get in this state all clients will eventually slow down.  Storage teams have reported everything looks good from a disk perspective.  Networking has reported the same.  The only thing the systems teams have noticed and haven't been able to explain is high load when we get in a bad state.

Please provide any input, suggestions, or configuration updates you may have.

#======================= Global Settings =====================================
[global]
# ----------------------- Network Related Options -------------------------
   workgroup = TSH
   server string = Samba Server Version %v
   password server = xx.xx.xx.211 xx.xx.xxx.212
   realm = xxx.COM
   security = ads
   username map = /etc/samba/smbusers
   smb passwd file = /etc/samba/smbpasswd
   idmap uid = 16777216-33554431
   idmap gid = 16777216-33554431
   template shell = /bin/sh
   winbind use default domain = yes
   winbind offline logon = false
   unix password sync = yes
   passwd program = /usr/bin/passwd %u
   passwd chat = *New*password* %n *Retype*new*password* %n *passwd:*all*authentication*token*updated*successfully*
   pam password change = yes
   obey pam restrictions = yes
   passdb backend = tdbsam
   log file = /var/log/samba/%m.log
   private dir = /var/
   encrypt passwords = yes
   netbios name = xxxxxP1
# --------------------------- Logging Options -----------------------------

# ----------------------- Domain Controller Options ------------------------

# ----------------------- Browser Control Options ----------------------------

#----------------------------- Name Resolution -------------------------------

# --------------------------- Printing Options -----------------------------
        load printers = yes
        cups options = raw
# --------------------------- Filesystem Options ---------------------------
        map hidden = no
        map read only = no
        store dos attributes = yes
        dos charset = CP850
        unix charset = UTF-8
        display charset = LOCALE
        mangling char = ~
        create mask = 0775
        directory mask = 0775
        acl check permissions = true
        acl compatibility = win2k
        inherit permissions = yes
#============================ Share Definitions ==============================
[denshr]
        comment = Den Share for windows
        path = /opt/share/denshr
        browseable = yes
        writable = yes
        create mode = 0775
        valid users = xyz TSH\xyz
[test]
        comment = Den Share for windows
        path = /opt/tibco-tm
        browseable = yes
        writable = yes
        create mode = 0775
        valid users = xyz TSH\xyz


Brian