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Date: Sun, 5 Nov 2000 12:21:54 -0800 (PST)
From: dean gaudet <dean-list-linux-kernel@arctic.org>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
cc: Linus Torvalds <torvalds@transmeta.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Re: Negative scalability by removal of
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the numbers didn't look that bad for the small numbers of concurrent
clients on 2.2... a few % slower without the serialisation.  compared to
orders of magnitude slower with large numbers of concurrent client.

oh, someone reminded me of the other reason sysvsems suck:  a cgi can grab
the semaphore and hold it, causing a DoS.  of course folks could, and
should use suexec/cgiwrap to avoid this.

-dean

On Sat, 4 Nov 2000, Alan Cox wrote:

> > Even 2.2.x can be fixed to do the wake-one for accept(), if required. 
> 
> Do we really want to retrofit wake_one to 2.2. I know Im not terribly keen to
> try and backport all the mechanism. I think for 2.2 using the semaphore is a 
> good approach. Its a hack to fix an old OS kernel. For 2.4 its not needed
> -
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