Winbindd limited by select

[Esh, Andrew]

Better yet: Have winbindd fork the same way smbd does, on a per-client
basis.

Someone should probably figure out what quality of the example network
caused winbindd to consume so many sockets. Are there really that many
requests being queued up at once? Shifting to a forking model would simply
consume the same number and more processes. They are limited too.

We also need to be sure all the requests are making progress. If one gets
hung, the client program would probably repeat the request, expending
another instance of everything. Are there really 2048 users actively trying
to make winbindd requests at the same time?

Perhaps this is the result of a very network-common failed NIS request,
which falls through the passwd list in /etc/nsswitch.conf, and winds up
asking winbindd about the same non-existent user. What is the content of the
requests, and is there some way to fix the system so the users don't cause
them to be issued at such a high rate? Should they even be forwarded to
winbindd at all?

Maybe winbindd is piling up requests as it searches for a domain controller
at the head of its "password server" list which is no longer working, or is
no longer in DNS. Reorder that list, and winbindd might begin to process
requests fast enough to stay ahead of the influx rate.

> -----Original Message-----
> From: Martin Pool [mailto:mbp at samba.org]
> Sent: Wednesday, February 12, 2003 5:56 PM
> To: Michael Steffens
> Cc: Ken Cross; 'Multiple recipients of list SAMBA-TECHNICAL'
> Subject: Re: Winbindd limited by select
> 
> 
> On 12 Feb 2003, Michael Steffens <michael.steffens at hp.com> wrote:
> 
> > It's 60 by default after installation, but is tunable (with reboot).
> 
> Maybe hp should sell per-fd licences :-/
> 
> > The solution (and this should also work on other platforms) was to
> > have winbindd housekeep its client connections by shutting down
> > idle connections, and have clients reconnect when required:
> > 
> >   
> http://lists.samba.org/pipermail/samba-technical/2003-February
/042210.html
> 
> The threshold was chosen to be 100 active connections, which keeps
> winbindd well below 300 FDs. Below 140, actually, including network
> sockets and open database and log files.

I wonder how well it would work to have one winbindd process per n
clients, in addition to shutting down idle clients...

-- 
Martin