Printing to CUPS via SAMBA shared printer slow

We have a Debian print server running CUPS. In CUPS we have a Raw print queue configured that connects to our networked printer via IPP. I've also shared this printer to our Windows users via a Samba printer share, using pretty stock standard smb.conf options and CUPS as the backend. When printing directly to the CUPS queue from Windows using IPP (eg. http://cups-server:631/printers/printer-name) , the printer responds quickly and prints almost instantly. However, when printing to the print queue via the shared Samba printer on Windows, the printer takes over 15 seconds to open the Printer Properties window, and the same amount of time to print a test page. Whilst trying to deduce the cause, I've been able to reproduce the issue on two completely separate networks with two different print servers and printers, and numerous different Windows clients, so I am confident it is not specific to my individual installs. Using both IP addresses and host names results in the same behavior. Are there any options or settings that need to be tweaked to speed up printing from Samba shared printers? I am running CUPS 2.2.1 and Samba 4.5.12. I can also reproduce the same behavior on an older server running CUPS 1.7.5 and Samba 4.2.14. My smb.conf follows. Everything is the defaults from the stock Debian smb.conf except for the first 4 options under the Printing heading.
*I've removed all the large blocks of unrelated comments from the default smb.conf* [global] ## Printing ## # Enable the spoolssd Service rpc_server:spoolss = external rpc_daemon:spoolssd = fork # Set minimum spoolssd pool spoolssd:prefork_min_children = 2 # Set printing backend to CUPS printing = CUPS ## Browsing/Identification ### # Change this to the workgroup/NT-domain name your Samba server will part of workgroup = WORKGROUP # Windows Internet Name Serving Support Section: # WINS Support - Tells the NMBD component of Samba to enable its 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 # This will prevent nmbd to search for NetBIOS names through DNS. dns proxy = no #### Debugging/Accounting #### # This tells Samba to use a separate log file for each machine # that connects log file = /var/log/samba/log.%m # Cap the size of the individual log files (in KiB). max log size = 1000 # We want Samba to log a minimum amount of information to syslog. Everything # should go to /var/log/samba/log.{smbd,nmbd} instead. If you want to log # through syslog you should set the following parameter to something higher. syslog = 0 # Do something sensible when Samba crashes: mail the admin a backtrace panic action = /usr/share/samba/panic-action %d ####### Authentication ####### # Server role. Defines in which mode Samba will operate. Possible # values are "standalone server", "member server", "classic primary # domain controller", "classic backup domain controller", "active # directory domain controller". # # Most people will want "standalone sever" or "member server". # Running as "active directory domain controller" will require first # running "samba-tool domain provision" to wipe databases and create a # new domain. server role = standalone server # If you are using encrypted passwords, Samba will need to know what # password database type you are using. passdb backend = tdbsam obey pam restrictions = yes # This boolean parameter controls whether Samba attempts to sync the Unix # password with the SMB password when the encrypted SMB password in the # passdb is changed. unix password sync = yes # For Unix password sync to work on a Debian GNU/Linux system, the following # parameters must be set (thanks to Ian Kahan for # sending the correct chat script for the passwd program in Debian Sarge). passwd program = /usr/bin/passwd %u passwd chat = *Enter\snew\s*\spassword:* %n\n *Retype\snew\s*\spassword:* %n\n *password\supdated\ssuccessfully* . # This boolean controls whether PAM will be used for password changes # when requested by an SMB client instead of the program listed in # 'passwd program'. The default is 'no'. pam password change = yes # This option controls how unsuccessful authentication attempts are mapped # to anonymous connections map to guest = bad user # Allow users who've been granted usershare privileges to create # public shares, not just authenticated ones usershare allow guests = yes #======================= Share Definitions ======================= [homes] comment = Home Directories browseable = no # By default, the home directories are exported read-only. Change the # next parameter to 'no' if you want to be able to write to them. read only = yes # File creation mask is set to 0700 for security reasons. If you want to # create files with group=rw permissions, set next parameter to 0775. create mask = 0700 # Directory creation mask is set to 0700 for security reasons. If you want to # create dirs. with group=rw permissions, set next parameter to 0775. directory mask = 0700 # By default, \\server\username shares can be connected to by anyone # with access to the samba server. # The following parameter makes sure that only "username" can connect # to \\server\username # This might need tweaking when using external authentication schemes valid users = %S # Un-comment the following and create the netlogon directory for Domain Logons # (you need to configure Samba to act as a domain controller too.) ;[netlogon] ; comment = Network Logon Service ; path = /home/samba/netlogon ; guest ok = yes ; read only = yes # Un-comment the following and create the profiles directory to store # users profiles (see the "logon path" option above) # (you need to configure Samba to act as a domain controller too.) # The path below should be writable by all users so that their # profile directory may be created the first time they log on ;[profiles] ; comment = Users profiles ; path = /home/samba/profiles ; guest ok = no ; browseable = no ; create mask = 0600 ; directory mask = 0700 [printers] path = /var/spool/samba printable = yes # Windows clients look for this share name as a source of downloadable # printer drivers [print$] comment = Printer Drivers path = /var/lib/samba/printers browseable = yes read only = yes guest ok = no # Uncomment to allow remote administration of Windows print drivers. # You may need to replace 'lpadmin' with the name of the group your # admin users are members of. # Please note that you also need to set appropriate Unix permissions # to the drivers directory for these users to have write rights in it ; write list = root, @lpadmin Here are relevant printing defaults being set by Samba:
_testparm -sv | grep -Ei --color '(print|drive|spool|devmode)'_ Processing section "[homes]" Processing section "[printers]" Processing section "[print$]" Loaded services file OK. Server role: ROLE_STANDALONE load printers = Yes printcap cache time = 750 printcap name = iprint server = disable spoolss = No addprinter command = deleteprinter command = show add printer wizard = Yes os2 driver map = logon drive = dcerpc endpoint servers = epmapper, wkssvc, rpcecho, samr, netlogon, lsarpc, spoolss, drsuapi, dssetup, unixinfo, browser, eventlog6, backupkey, dnsserver spoolssd:prefork_min_children = 2 rpc_daemon:spoolssd = fork rpc_server:spoolss = external min print space = 0 max reported print jobs = 0 max print jobs = 1000 printable = No print notify backchannel = No print ok = No printing = cups print command = printer name = use client driver = No default devmode = Yes force printername = No printjob username = %U [printers] path = /var/spool/samba printable = Yes print ok = Yes [print$] comment = Printer Drivers path = /var/lib/samba/printers