From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sonic305-20.consmr.mail.ir2.yahoo.com (sonic305-20.consmr.mail.ir2.yahoo.com [77.238.177.82]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 6D0333BA8E for ; Mon, 9 Oct 2017 09:10:04 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.fr; s=s2048; t=1507554603; bh=IGVfE1VACVzO7yxUh3JbQVP1Q1njnpM7fsu6SScMuKU=; h=Subject:To:References:From:Date:In-Reply-To:From:Subject; b=md0rILkP/QeBCvG6p4lNepAVc0uJPGwWblgt8+BUwjQmOeyFVTX9d6m5HDxj5/o6X/zWdqmdKzOWDV4ZARiVNLjDMql1NSo5jXXTH9WVoImaLxyOTYObGP6ncUutTtbKi9DFxF8vMhucYSkiD36uQBNJj78BnEQdbgCmDns60BQf6g6WCRVYup+G6uGj9ezS5oZO94g2qjiNQWOClYwaHg3/CmfCdkr2EZ5w9A5gAmc04OWL+49wKpIFJADrQqp3NMa0PAnYrn8Y0DcZ0V7SoPYDDSi9/pjR36U5Go49zmkRS8TtB4d6XcrPd6rJA2xwVArCgw7n5A7Oj2kQbDWOyQ== X-YMail-OSG: J1agPSsVM1l_772n1D4fmTI.ObmH9Qa6vdAVYEdh3aFUrm_JK3NDDCU5JuLNbfq WRzXgAvUrWMauW7MwcSt2vLzkkw8YUb8W_7Yl8CgC76exkkk15FgJGViSExXXTm_XWHjdBwporQg qMeu14tEqOBSbZY6VznhlbGMYuPzntdbM8MApji3RvdWZ2G7z2E_e.FXwqGTIRMsrr4Wwb0zPtdm ucNPoH_bbf93.Go4J3XHkDaAzm4rkE1eFr7tRc_TC98NlLWi_KhqGhJhrWaZWxWy2LKLrT4su7cR ngrCLRjYoxtVTUS1jEns34AQdtMxfqTM_4Ln83HCqYKDb_K3IiSLJEWwWWZeWXg4mjthG8s08pz. yfHNuzWEYGCZSeQkJBxKznUJTDCImaMkrvPevyAFEXRMSYFPg6DmeJ3F_o3ru.zcfJFGLPZgWHPM wr3VJFDkOooOVlKBw8Mx0fz5tVoodi9vDHtqQhBn7QaxksJkfrkrse9OAxB3AR0mbbrn1gRYA2b. MOCAwpgGx Received: from sonic.gate.mail.ne1.yahoo.com by sonic305.consmr.mail.ir2.yahoo.com with HTTP; Mon, 9 Oct 2017 13:10:03 +0000 Received: from [127.0.0.1] by smtp117.mail.ir2.yahoo.com with NNFMP; 09 Oct 2017 13:09:59 -0000 X-Yahoo-Newman-Id: 454378.73069.bm@smtp117.mail.ir2.yahoo.com X-Yahoo-Newman-Property: ymail-3 X-YMail-OSG: J1agPSsVM1l_772n1D4fmTI.ObmH9Qa6vdAVYEdh3aFUrm_ JK3NDDCU5JuLNbfqWRzXgAvUrWMauW7MwcSt2vLzkkw8YUb8W_7Yl8CgC76e xkkk15FgJGViSExXXTm_XWHjdBwporQgqMeu14tEqOBSbZY6VznhlbGMYuPz ntdbM8MApji3RvdWZ2G7z2E_e.FXwqGTIRMsrr4Wwb0zPtdmucNPoH_bbf93 .Go4J3XHkDaAzm4rkE1eFr7tRc_TC98NlLWi_KhqGhJhrWaZWxWy2LKLrT4s u7cRngrCLRjYoxtVTUS1jEns34AQdtMxfqTM_4Ln83HCqYKDb_K3IiSLJEWw WWZeWXg4mjthG8s08pz.yfHNuzWEYGCZSeQkJBxKznUJTDCImaMkrvPevyAF EXRMSYFPg6DmeJ3F_o3ru.zcfJFGLPZgWHPMwr3VJFDkOooOVlKBw8Mx0fz5 tVoodi9vDHtqQhBn7QaxksJkfrkrse9OAxB3AR0mbbrn1gRYA2b.MOCAwpgG x X-Yahoo-SMTP: R8REcOaswBA8tpUVQfvLNOMJ0vXRwYHSeLQ- To: bloat@lists.bufferbloat.net References: From: Y Message-ID: <1545372c-86df-2c03-72c1-d7f146ae6b16@yahoo.fr> Date: Mon, 9 Oct 2017 22:09:55 +0900 User-Agent: Mozilla/5.0 (X11; Linux i686; rv:52.0) Gecko/20100101 Thunderbird/52.3.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Subject: Re: [Bloat] emulating non-duplex media in linux qdiscs X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 09 Oct 2017 13:10:04 -0000 Interesting :) On 2017年10月09日 10:54, Dave Taht wrote: > I have been hacking away at netem for a while now in the hope that > eventually - with a great deal more hacking - it could be used to more > accurately emulate shared media like wifi and lte. > > (Some people try to describe these as simplex (which is not true > because you can have multiple destinations), and they certainly are > not duplex, so I tend to say non-duplex and still hope some better > word emerges) > > So... one sticking point for me has been wanting to emulate the fact > that on shared media, that you cannot transmit and receive at the same > time; that these are "coupled" events, and what I'd like to be able to > express might be something like: > > tc qdisc add dev eth0 root netem rate 100mbit coupled some_identifier > ... some tc mirred magic for ifb here ... > tc qdisc add dev ifb0 root netem rate 10mbit coupled the_same_identifier > > "some_identifier" would be a mutex of some sort, and I confess to > not having much grip on the kernel outside of the net/sched directory. > > What facility would be best to try and leverage? It would be created > (globally) on first use, ref-counted (thus destroyed when it goes to > zero), atomically updated... posix shared memory seems too heavyweight > to use.... >