Re: [libmicrohttpd] Performance problem under Windows

[Martin Bisson]

On 09/02/2011 8:55 AM, Christian Grothoff wrote:
> > I find the "little more than 1 second per request" a little suspicious.
> > I looked at the code in daemon.c and both the select() and the poll()
> > calls use a 1 second timeout...  I was wondering if there might be a
> > problem with that under Windows...?  Or is the 1 second per request an
> > expected latency for libmicrohttpd with client&  server on the same
> > computer?
> Well, I don't know how the 1s timeout in select relates to your performance
> issue (have you tried changing it to 10s and seeing if performance goes down
> accordingly), but what I can say is that MHD has no expected latency -- it
> should be "instant" (as far as your OS/hardware can deliver).
>
> Now, 0.4.5 is of course ancient and various issues have been introduced and
> fixed since (see ChangeLog), so I don't know if you're possibly hitting one of
> those.

Ok.  I rebuilt libmicrohttpd-0.9.6 and tried, still the same problem.  I 
changed the poll & select timeouts to 10 ms, no change.  I tried my 
python script with a local Apache server, and I get low latency.

But still, with libmicrohttpd, I get latencies that are slightly above 1 
s.  So I really feel, like something is still waiting for 1 s 
somewhere.  I identified that the waiting is after my request is sent 
and before my request-handling callback is called by libmicrohttpd, but 
I don't really how to identify the problem...

Any idea what to do next to get libmicrohttpd to respond faster?

Thanks in advance,

Martin