Does named use multithreading?

[David R. Conrad]

Just to be clear, BIND version 8 is event driven using a select() loop and 
BIND version 9 is event driven with multiple threads (each thread handling 
a queue of events).  On a single processor system, the result is 
essentially the same (some argue that the threading overhead make the 
multi-thread model less efficient, but I haven't seen any evidence of this 
in practice).

The difference isn't particularly relevant to answering queries.  Where the 
BINDv9 model definitely wins in when is when it is reloading zones.  BINDv8 
goes deaf.  BINDv9 continues to answer queries.

Rgds,
-drc

At 08:10 PM 11/16/2000 +0100, Christophe Deleuze wrote:
>Joseph S D Yao <jsdy at cospo.osis.gov> writes:
>
> > On Thu, Nov 16, 2000 at 09:54:24AM -0800, Kathy Musson wrote:
> > > I am trying to understand how named handles multiple
> > > simultaneous requests.  Does it handle each request
> > > sequentially, or does it fork threads to handle each request
> > > somewhat simultaneously?  It seems like it should have to
> > > do some sort of multithreading to be able to handle a large
> > > volume of requests...
> >
> > BIND 9 does, I believe.  BIND 8 does not, hence some of the delay in
> > responses.
>
>Bind9 is multi-threaded, bind8 is not.  Multi-threading can help handle a
>large rate of requests if the machine has several processors.  On a single
>CPU machine, I don't think it can impact performance significantly.
>
>--
>Dr. Christophe Deleuze          Christophe.Deleuze at ActiVia.net
>ActiVia Networks                http://www.activia.net