samba - Oct 2023 - Is it possible to reduce the number of workers for rpcd_winreg?

Dear Samba Group,

I recently updates our samba addc's to 4.18.6 (from 4.7.7). We use roaming
profile and a login script which queries active shares and printers on the logon
servers. Since the update i see a lot of
rpcd_winreg processes if an user logs on. It are around 40 of these processes
each consuming around 60MB. The servers have 1-2GB of ram assigned so they start
swapping everytime an user logs on. The
processes disappear after 1-2 Minutes and the free memory goes back from 50MB to
~1.2GB (on an 2GB server).
Is there a way to limit the number of workers so i can avoid swapping?
So far i found "prefork backoff increment", "prefork
children" and "prefork maximum backoff" variables which are
related to the workers but these are not helpful in my case.

The operating system is debian bookworm.

smb.conf

[global]
??????? workgroup = DOMAIN
??????? realm = domain.loc
??????? netbios name = SERVER

??????? logging = syslog
??????? log level = 0

??????? usershare path 
??????? interfaces = 192.168.0.1 127.0.0.1
??????? bind interfaces only = yes

??????? server role = active directory domain controller
??????? dns forwarder = 192.168.0.200

??????? idmap_ldb:use rfc2307 = yes
??????? idmap config * : range = 3000000-4000000
??????? ldap server require strong auth = no
??????? kccsrv:samba_kcc = no
??????? deadtime = 10

.......


Thanks in advance,
Achim~

As recommended by Volker Lendecke I added the option.

rpcd_winreg:idle_seconds = 5 Now on 2GB Servers swapping is avoided and on 1Gb
Servers the server goes back to normal in ~5 seconds after the logon process has
finished.

Am 10.10.2023 um 13:58 schrieb Achim Gottinger via samba:
> Dear Samba Group,
>
> I recently updates our samba addc's to 4.18.6 (from 4.7.7). We use
roaming profile and a login script which queries active shares and printers on
the logon servers. Since the update i see a lot of
> rpcd_winreg processes if an user logs on. It are around 40 of these
processes each consuming around 60MB. The servers have 1-2GB of ram assigned so
they start swapping everytime an user logs on. The
> processes disappear after 1-2 Minutes and the free memory goes back from
50MB to ~1.2GB (on an 2GB server).
> Is there a way to limit the number of workers so i can avoid swapping?
> So far i found "prefork backoff increment", "prefork
children" and "prefork maximum backoff" variables which are
related to the workers but these are not helpful in my case.
>
> The operating system is debian bookworm.
>
> smb.conf
>
> [global]
> ??????? workgroup = DOMAIN
> ??????? realm = domain.loc
> ??????? netbios name = SERVER
>
> ??????? logging = syslog
> ??????? log level = 0
>
> ??????? usershare path >
> ??????? interfaces = 192.168.0.1 127.0.0.1
> ??????? bind interfaces only = yes
>
> ??????? server role = active directory domain controller
> ??????? dns forwarder = 192.168.0.200
>
> ??????? idmap_ldb:use rfc2307 = yes
> ??????? idmap config * : range = 3000000-4000000
> ??????? ldap server require strong auth = no
> ??????? kccsrv:samba_kcc = no
> ??????? deadtime = 10
>
> .......
>
>
> Thanks in advance,
> Achim~
>
>