From owner-freebsd-net@freebsd.org Tue Sep 24 22:19:36 2019 Return-Path: Delivered-To: freebsd-net@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id B0E1FF36DB for ; Tue, 24 Sep 2019 22:19:36 +0000 (UTC) (envelope-from freebsd-rwg@gndrsh.dnsmgr.net) Received: from gndrsh.dnsmgr.net (br1.CN84in.dnsmgr.net [69.59.192.140]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 46dFwl5zW8z46g6; Tue, 24 Sep 2019 22:19:35 +0000 (UTC) (envelope-from freebsd-rwg@gndrsh.dnsmgr.net) Received: from gndrsh.dnsmgr.net (localhost [127.0.0.1]) by gndrsh.dnsmgr.net (8.13.3/8.13.3) with ESMTP id x8OMJP9N013499; Tue, 24 Sep 2019 15:19:25 -0700 (PDT) (envelope-from freebsd-rwg@gndrsh.dnsmgr.net) Received: (from freebsd-rwg@localhost) by gndrsh.dnsmgr.net (8.13.3/8.13.3/Submit) id x8OMJP3P013498; Tue, 24 Sep 2019 15:19:25 -0700 (PDT) (envelope-from freebsd-rwg) From: "Rodney W. Grimes" Message-Id: <201909242219.x8OMJP3P013498@gndrsh.dnsmgr.net> Subject: Re: dummynet: bandwidth is limited to 2 Gbit/s ? In-Reply-To: <5D8A3D35.5050303@grosbein.net> To: Eugene Grosbein Date: Tue, 24 Sep 2019 15:19:25 -0700 (PDT) CC: Andriy Gapon , freebsd-net X-Mailer: ELM [version 2.4ME+ PL121h (25)] MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII X-Rspamd-Queue-Id: 46dFwl5zW8z46g6 X-Spamd-Bar: +++ Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=none; spf=none (mx1.freebsd.org: domain of freebsd-rwg@gndrsh.dnsmgr.net has no SPF policy when checking 69.59.192.140) smtp.mailfrom=freebsd-rwg@gndrsh.dnsmgr.net X-Spamd-Result: default: False [3.64 / 15.00]; ARC_NA(0.00)[]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_THREE(0.00)[3]; IP_SCORE(0.04)[ip: (0.15), ipnet: 69.59.192.0/19(0.07), asn: 13868(0.04), country: US(-0.05)]; MIME_GOOD(-0.10)[text/plain]; MIME_TRACE(0.00)[0:+]; DMARC_NA(0.00)[dnsmgr.net]; AUTH_NA(1.00)[]; NEURAL_SPAM_MEDIUM(0.91)[0.914,0]; TO_MATCH_ENVRCPT_SOME(0.00)[]; TO_DN_ALL(0.00)[]; NEURAL_SPAM_LONG(0.78)[0.783,0]; R_SPF_NA(0.00)[]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; SUBJECT_ENDS_QUESTION(1.00)[]; ASN(0.00)[asn:13868, ipnet:69.59.192.0/19, country:US]; MID_RHS_MATCH_FROM(0.00)[]; RCVD_TLS_LAST(0.00)[]; RCVD_COUNT_TWO(0.00)[2] X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 24 Sep 2019 22:19:36 -0000 > On 24.09.2019 12:42, Andriy Gapon wrote: > > > It seems that the userland component of ipfw/dummynet uses int for the bandwidth > > represented in bit/s. Also, int is used for passing that value from the > > userland to the kernel. > > > > What would be the best way to extend this? > > Just use a larger type? > > Or maybe add another field to try to preserve KBI backward compatibility? > > > > Thank you. > > AFAIK, we never had any public ABI or stable KBI interface announced to userland or in-kernel consumers > and had no consumers of dummynet other than ipfw(8) binary. Just increase type. Any attempt to mfc this would break KABI/userland and that is never a good thing to do. It may not be a public ABI, but it is an ABI, and stability of that and backwards compatibility are always a good thing to strive for. -- Rod Grimes rgrimes@freebsd.org