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Subject: RE: [PATCH] Apache 2.2.x: Implicit creation of new proxy_workers
Date: Mon, 17 Sep 2007 11:33:16 +0200
Message-ID: <C73DD414A1D3C847976D7E181BF4360C022AF8C0@exchange2k304.gaia.fr>
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Thread-Topic: [PATCH] Apache 2.2.x: Implicit creation of new proxy_workers
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From: =?iso-8859-1?Q?Axel-St=E9phane__SMORGRAV?=
 <Axel-Stephane.SMORGRAV@europe.adp.com>
To: <dev@httpd.apache.org>

-----Message d'origine-----
>De : Pl=FCm, R=FCdiger, VF-Group [mailto:ruediger.pluem@vodafone.com]=20
>Envoy=E9 : lundi 10 septembre 2007 12:02
>=C0 : dev@httpd.apache.org
>Objet : Re: [PATCH] Apache 2.2.x: Implicit creation of new =
proxy_workers
>
>> -----Urspr=FCngliche Nachricht-----
>> Von: Nick Kew
>> Gesendet: Montag, 10. September 2007 11:29
>> An: dev@httpd.apache.org
>> Betreff: Re: [PATCH] Apache 2.2.x: Implicit creation of new =
proxy_workers
>>=20
>> Does this open the way to a DoS?  If a rewriterule[P] enables =
backends=20
>> to be derived from the request URI, then you're creating unlimited=20
>> numbers of workers, which may never be used.  Where are the limits on =

>> that?
>
>Also the scoreboard is a limiting factor for this. The number of =
available=20
>scoreboard entries is determined during the configuration phase of the =
startup=20
>(it cannot even be changed during graceful starts, this is why we add =
some=20
>additional entries to the number of workers we have counted in the =
configuration).
>
>To be honest I am still not convinced that the dynamic creation of =
workers is a good idea at all.
>

I believe I have addressed your concerns in a new patch posted for =
PR#43308 in which I introduce a new configuration directive that limits =
the number of dynamically created workers. During configuration I also =
increment proxy_lb_workers by the value of ProxyMaxAddtlWorkers in order =
(at least I hope) for additional scoreboard entries to be allocated...

BR
-ascs