[Samba] High CPU While Loading RSAT Active Directory Users and Computers

[Andrew Bartlett]

On Fri, 2017-11-17 at 10:46 -0400, Dale Renton via samba wrote:
> Hello,
> 
> I'm trying to figure out a problem with our AD DC with the FSMO roles, name
> DC1.  When starting the Windows RSAT Active Directory Users and Computers
> program against DC1 it takes about 90 seconds to load.  A samba process on
> the server is at 100% CPU while waiting for it to load.  Once loaded the
> CPU goes back to normal.  When connecting the Active Directory Users and
> Computers program against DC2 though it loads in a couple of seconds.  DC1
> and DC2 are on two different identical physical servers with the same
> config.  When running strace on the 100% CPU process, most of the time is
> spent on the fcntl syscall.


> CentOS 7
> Samba 4.5.10
> 

I can't explain the difference but we did a lot of work for Samba 4.7
to address this issue, which is due to a locking bug. 

Andrew Bartlett
-- 
Andrew Bartlett                       http://samba.org/~abartlet/
Authentication Developer, Samba Team  http://samba.org
Samba Developer, Catalyst IT          http://catalyst.net.nz/services/samba