samba - Feb 2014 - Where do I get detailed information about oplock-types and possible errors?

Hello,

     I would like to know, what the oplock 'EXCLUSIVE+BATCH' exactly 
means. Does anybody know a good manual about samba's oplocks?

     Could it possibly cause oplock-trouble and even disconnections, if 
a user is constantly logged in on one AD-workstations and also 
frequently accesses network files from a WinXP+SP2 workstation (that is 
not part of the AD-Domain) via credentials?

Nice regards, bbb




Background-Information:

One of our AD-users is having severe problems with frequent 
disconnections from the AD-Domain. I've noticed that the user has quite 
a lot error messages, that look like this:

[2013/10/21 08:53:15.854203,  0] 
../source3/smbd/oplock.c:333(oplock_timeout_handler)
   Oplock break failed for file 
user_x/Anwendungsdaten/Thunderbird/Profiles/pfo6pijp.default/panacea.dat 
-- replying anyway

There's also something strage about the users locked files in smbstatus 
output: when any other user would use the oplock 'BATCH', the user with 
the problems always uses 'EXCLUSIVE+BATCH'

15306        3000035    DENY_NONE  0x2019f     RDWR EXCLUSIVE+BATCH  
/home/samba 
user_x/Anwendungsdaten/Thunderbird/Profiles/pfo6pijp.default/panacea.dat 
Wed Feb 12 14:56:34 2014
15311        3000038    DENY_NONE  0x12019f    RDWR BATCH            
/home/samba 
user_ok/Anwendungsdaten/Thunderbird/Profiles/i8g18axs.default/panacea.dat Wed 
Feb 12 09:09:46 2014

The user with the disconnection-problems is constantly working on two 
different workstations at the same time... unfortunately we have to use 
an additional WinXP+SP2 workstation for a special software, we need. I'm 
currently setting up a second account for this users - perhaps it will 
help. This is not a support-request, just a question/discussion.

Can anybody recommend a page, where I can find further details on the 
information in 'Chapter 17. File and Record Locking'?

I can't figure out, why one user uses the 'EXCLUSIVE+BATCH' oplock
for
it's thunderbird profile-data, while all the other users use the
'BATCH'
oplock for the same kind of files on the same share.

Nice regards, bbb