Re: [PATCH] Naive approach to HTTP-timeouts (Final?)

Hi Slava,

On Friday 28 November 2003 08:16, Vjacheslav Chekushin wrote:
> Hi, Alexander.
> First of all, test shows that _YAT_ approach works faster:
> THREAD-VERSION : Time taken for tests:   4.688475 seconds
> WITHOUT THREADS: Time taken for tests:   243.150797 seconds
> But, to be honest, I don't beleive in it.

Test doesn't show anything interesting, since it's simply inaccurate or wrong.
Have you notice this w/o YAT?:
Failed requests:        570
   (Connect: 0, Length: 570, Exceptions: 0)

Here is something wrong...

> The only choice for it: patch occasionaly remove some bug or
> perfomance bottleneck from sources.
>
> And can you explain about expected perfomance degradation in YAT aproach.
> Do you mean thread's swithing once at 20 seconds? I don't think so.
> IMHO kernel switches between threads _realy_ fast, because threads
> share the same address space, stack, code, etc.

I agree with you that thread start time is very small (and is to be 
neglected), but the more threads are running the more expensive is the 
scheduling (ok, I know, Linux 2.6 has O(1) scheduler ;))...
But the really question is: can we reach the same performance w/o YAT?
and if we can't then yes I am ++1 for YAT! But we should try/test it first...

>
> I remember the time when kannel created new thread for every outgoing http
> request. And even this worked pretty fast.
>
> Alexander Malysh wrote:
> > hey, factor 50???? I want see a patch w/o YAT!!!
> > It can't be soooo bad...
> >
> > On Thursday 27 November 2003 17:24, David Schmitz wrote:
> >>Hi,
> >>
> >>your YAT-hatred ;) is well known and understood. See the attachment for
> >>some naive benchmarks. Please draw your own conclusions.
> >>
> >>Regards,
> >>David
> >>
> >>Alexander Malysh schrieb:
> >>>Hi David/Slava,
> >>>
> >>>as you know, I do not like "yet another thread" (YAT) approach...
> >>>Would you please try get some benchmark results w/ and w/o YAT, so we
> >>> can see how is performance w/o YAT affected?
> >>>
> >>>Thanks in advance...
> >>>
> >>>On Thursday 27 November 2003 15:02, David Schmitz wrote:
> >>>>Hi list,
> >>>>
> >>>>attached is the IMHO final version of the timeout-patch.  I took the
> >>>>thread-approach as discussed with Slava (thanks for your input and help
> >>>>
> >>>>:)). If there are no objections/corrections I would like to commit the
> >>>>
> >>>>patch.
> >>>>
> >>>>Note: configuration of the timeout-values is done in http.h.
> >>>>
> >>>>Best regards,
> >>>>David

-- 
Best regards / Mit besten Grüßen aus Düsseldorf

Dipl.-Ing.
Alexander Malysh
___________________________________________

Centrium GmbH
Vogelsanger Weg 80
40470 Düsseldorf

Fon: +49 (0211) 74 84 51 80
Fax: +49 (0211) 277 49 109

email: [email protected]
web: www.centrium.de
msn: [email protected]
icq: 98063111
___________________________________________

Please avoid sending me Word, Excel or PowerPoint attachments.
See http://www.fsf.org/philosophy/no-word-attachments.html