[Samba] dcesrv process purpose

[Andrew Bartlett]

On Mon, 2018-09-03 at 09:10 +0200, Francesco Malvezzi via samba wrote:
> hi all,
> 
> after investigating a bit more about my performance problems, the task
> that spins at 100% cpu (once in a while) appears to be consistently dcesrv.
> 
> What is the dcesrv role's purpose?
> 
> Which is the samba log facility that captures dcesrv activities?
> 
> thank you,

Can you be a bit more specific about the exact process name causing you
trouble?  

DCE/RPC is at the core of Samba's capability as an AD DC, covering
important protocols like NETLOGON (NTLM auth), LSA (name/SID lookups,
trust handling), SAMR (user administration) and DRSUAPI (replication).

Additionally, there is the similarly named dreplsrv sub-process which
handles the 'client' side of replication, pulling and pushing changes
as required to other DCs.

Finally, I would say that 50k users is not a mid-sided domain for Samba
as an AD DC, indeed it is one of the largest I've heard of.  If so, it
is quite likely that you are hitting some scaling issues.

We continue to improve Samba's AD DC performance at this scale, but
while we have also identified a number of potential improvements we
haven't had the opportunity to action those yet[1].

Thanks,

Andrew Bartlett

[1] Help financing Samba at scale most welcome. 

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