From owner-freebsd-hackers@FreeBSD.ORG  Wed Nov 12 22:31:54 2014
Return-Path: <owner-freebsd-hackers@FreeBSD.ORG>
Delivered-To: freebsd-hackers@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115])
 (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits))
 (No client certificate requested)
 by hub.freebsd.org (Postfix) with ESMTPS id ABF06BB1;
 Wed, 12 Nov 2014 22:31:54 +0000 (UTC)
Received: from mail-yk0-x22e.google.com (mail-yk0-x22e.google.com
 [IPv6:2607:f8b0:4002:c07::22e])
 (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits))
 (Client CN "smtp.gmail.com",
 Issuer "Google Internet Authority G2" (verified OK))
 by mx1.freebsd.org (Postfix) with ESMTPS id 692B32FD;
 Wed, 12 Nov 2014 22:31:54 +0000 (UTC)
Received: by mail-yk0-f174.google.com with SMTP id q9so1497709ykb.5
 for <multiple recipients>; Wed, 12 Nov 2014 14:31:53 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113;
 h=mime-version:sender:in-reply-to:references:date:message-id:subject
 :from:to:cc:content-type;
 bh=pQpbvL1Y2Ghy+mFNY45f+N7SgDZqRLSnPeBxdZWSJEk=;
 b=Az5uJEvrTbY9Gpqs+029AtZMR5vbngvGkyo26Rfix34SGyJwFESIZoloUm06mxa6/h
 d3tISkWN/oSk1+JRKfzo85kvUa5Q16xRsSl07xRWXzH05GLzPNJLlxyYuVR0XiXIrfL+
 m1+UM/4/pz5h2IsNrZHuPeH1+NpQGLVhKut1IoqR+3pj3rI3+aqFodAe587wugnfj6Sq
 ydb2c7LztjOUW8tkUrO58CJEr4scmoUC6GHUFvGSeRVRZqBWGNKR3t9EORgZbZWs9fPG
 dpQl920YSK7v3fylmzV3sIa8yQWNJet+6rbMmHbIhXN74OaXyBheGdj8y775eIeyHDtQ
 iZxQ==
MIME-Version: 1.0
X-Received: by 10.170.122.203 with SMTP id o194mr25648651ykb.10.1415831513005; 
 Wed, 12 Nov 2014 14:31:53 -0800 (PST)
Sender: kmacybsd@gmail.com
Received: by 10.170.82.197 with HTTP; Wed, 12 Nov 2014 14:31:52 -0800 (PST)
In-Reply-To: <CABXB=RTsktT7U1r5yzmwWVpJoiNFJBeT-in30r9rdo-tT-rfhQ@mail.gmail.com>
References: <CABXB=RQWxu-d30raZ+FcrnrGsr5gG2Za_=cx8-jCnLSgJDSF=Q@mail.gmail.com>
 <20141110071353.GO24601@funkthat.com>
 <CABXB=RStLz6J9L3--KsM308-0h0N5ZeZZvw1GbDi+ZvKO4U64g@mail.gmail.com>
 <20141112084909.GV24601@funkthat.com>
 <CAHM0Q_MJjH=Cq0AKTn64RkzgwPBMoKnDVu-GvcX6qBcFYDMpOg@mail.gmail.com>
 <CABXB=RTsktT7U1r5yzmwWVpJoiNFJBeT-in30r9rdo-tT-rfhQ@mail.gmail.com>
Date: Wed, 12 Nov 2014 14:31:52 -0800
X-Google-Sender-Auth: foF3vQSJz3-SspixqtjQYZEhPbQ
Message-ID: <CAHM0Q_OXUf5FDX485L0osdfsoYj7bgPCr==h0=_tuaq7RGnP7g@mail.gmail.com>
Subject: Re: How thread-friendly is kevent?
From: "K. Macy" <kmacy@freebsd.org>
To: J David <j.david.lists@gmail.com>
Content-Type: text/plain; charset=UTF-8
Cc: "freebsd-hackers@freebsd.org" <freebsd-hackers@freebsd.org>,
 "freebsd-questions@freebsd.org" <freebsd-questions@freebsd.org>
X-BeenThere: freebsd-hackers@freebsd.org
X-Mailman-Version: 2.1.18-1
Precedence: list
List-Id: Technical Discussions relating to FreeBSD
 <freebsd-hackers.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/options/freebsd-hackers>, 
 <mailto:freebsd-hackers-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-hackers/>
List-Post: <mailto:freebsd-hackers@freebsd.org>
List-Help: <mailto:freebsd-hackers-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hackers>,
 <mailto:freebsd-hackers-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Wed, 12 Nov 2014 22:31:54 -0000

Well, this was 8 cores with 45 or so processes. I'm not saying it
won't scale smoothly, but it did not in the past for lighttpd. Perhaps
it would have with some changes.

-K

On Wed, Nov 12, 2014 at 2:29 PM, J David <j.david.lists@gmail.com> wrote:
> On Wed, Nov 12, 2014 at 5:14 PM, K. Macy <kmacy@freebsd.org> wrote:
>> This may not be related, but it's interesting: a client I worked for
>> many years ago switched from kqueue to poll for their web server
>> because kqueue did not distribute the workload evenly. I imagine this
>> is unchanged.
>
> It looks pretty good in testing:
>
> $ ./kqtest server
>
> Server thread ends after 2630979 events.
>
> Server thread ends after 2600452 events.
>
> Server thread ends after 2525542 events.
>
> Server thread ends after 2418386 events.
>
> Server thread ends after 2524895 events.
>
> $
>
>
> That's a small-scale test on a VM with two CPU's running five threads,
> but the results appear to hold.  (This is using the _DISPATCH model.)
>
> Thanks!