From owner-freebsd-current@FreeBSD.ORG Thu May 29 04:45:34 2014 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id C75D6D3D for ; Thu, 29 May 2014 04:45:34 +0000 (UTC) Received: from mail-qg0-x231.google.com (mail-qg0-x231.google.com [IPv6:2607:f8b0:400d:c04::231]) (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 86DFE29A5 for ; Thu, 29 May 2014 04:45:34 +0000 (UTC) Received: by mail-qg0-f49.google.com with SMTP id a108so20544810qge.22 for ; Wed, 28 May 2014 21:45:33 -0700 (PDT) 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=xnDY2qVuvT0LLJkbD82FJIsuWFg7qPCMd8R1Xb05LNw=; b=LU7zIdKw6t0JNW3NQYuL7p2MPJrANil3ISGNvQwiGFtaDFiMtQ3Jfr5KViFHPRdBVp M6o+p7VEl8Jri6x27AMe6qQ3lda9SiKtBR4+poQeYIGl9DSi5n8DwChMAK/ZvxR+Lfrk ISeb7mnoR74RuSwo9Kp1x03TGMw8xkhlfYuufyBwH+kYybZL0Ext5F58havyDZKbFW65 ge1dnyTHWtFjG+mbTLCBTS5jnRXLeFX0L3ZUe/KUaKTPD7aEeF0K6nzSaOoLXzEUXTA8 7iJBEBiUQOm594XdLGhppdoYsdMSgNz3vOB3IvQhWiM/Z+66iABPC9GCFlnhmexd6U3+ OzGA== MIME-Version: 1.0 X-Received: by 10.224.37.10 with SMTP id v10mr6062989qad.98.1401338733522; Wed, 28 May 2014 21:45:33 -0700 (PDT) Sender: adrian.chadd@gmail.com Received: by 10.224.191.201 with HTTP; Wed, 28 May 2014 21:45:33 -0700 (PDT) In-Reply-To: References: <00c301cf7aee$b00caea0$10260be0$@rlwinm.de> Date: Wed, 28 May 2014 21:45:33 -0700 X-Google-Sender-Auth: G7vdOhngP5KzCBAYDJpuNyJDnpw Message-ID: Subject: Re: KQueue vs Select (NetMap) From: Adrian Chadd To: Fred Pedrisa Content-Type: text/plain; charset=UTF-8 Cc: freebsd-current , Jan Bramkamp X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 29 May 2014 04:45:35 -0000 The advantage is being able to include it in the rest of a kqueue IO loop where it's doing other things. -a On 28 May 2014 20:53, Fred Pedrisa wrote: > Hello, > > Yes, but kqueue support was added in recent commits as it says in the netmap > changelog, is there any advantage ? > > -----Mensagem original----- > De: owner-freebsd-current@freebsd.org > [mailto:owner-freebsd-current@freebsd.org] Em nome de Jan Bramkamp > Enviada em: quinta-feira, 29 de maio de 2014 00:30 > Para: freebsd-current@freebsd.org > Assunto: Re: KQueue vs Select (NetMap) > > > On 29.05.2014 03:04, Fred Pedrisa wrote: >> Hey Guys, >> >> >> >> How does kQueue performs over select with netmap ? > You are asking for a comparison between apples and oranges. Netmap is an API > for high performance access to the low-level features of modern NICs. It > works on batches of frames in hardware queues. > > The kqueue() and kevent() system calls are an event notification API. It is > mostly used by application dealing with a large amount of non-blocking > sockets (or other file descriptors). It reduces overhead inherent in > select() and poll() by preserving state between calls. It also supports > multiple types of events (read ready, write ready, timer expired, async i/o, > etc.). > > Afaik the netmap pseudo-device supports only select() and poll(). This is no > performance problem because every thread will only deal with a small number > of file descriptors to netmap devices. > > Netmap is designed to bypass the FreeBSD IP stack (for most frames). > Kqueue is designed to scale to many sockets per process within the FreeBSD > IP stack. > _______________________________________________ > freebsd-current@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-current > To unsubscribe, send any mail to "freebsd-current-unsubscribe@freebsd.org" > > _______________________________________________ > freebsd-current@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-current > To unsubscribe, send any mail to "freebsd-current-unsubscribe@freebsd.org"