From owner-freebsd-questions@freebsd.org Tue Apr 21 15:18:08 2020 Return-Path: Delivered-To: freebsd-questions@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 20C1B2A87E5 for ; Tue, 21 Apr 2020 15:18:08 +0000 (UTC) (envelope-from tundra@tundraware.com) Received: from oceanview.tundraware.com (oceanview.tundraware.com [45.55.60.57]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "mailman.tundraware.com", Issuer "mailman.tundraware.com" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 4966dV3w3Gz4Rbd for ; Tue, 21 Apr 2020 15:18:06 +0000 (UTC) (envelope-from tundra@tundraware.com) Received: from [192.168.0.2] (ozzie.tundraware.com [75.145.138.73]) (authenticated bits=0) by oceanview.tundraware.com (8.15.2/8.15.2) with ESMTPSA id 03LFHxdL054244 (version=TLSv1.2 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO) for ; Tue, 21 Apr 2020 10:17:59 -0500 (CDT) (envelope-from tundra@tundraware.com) Subject: Re: More On FreeBSD Network Speed (Was: Changes To nat-ing Behaviour?) From: Tim Daneliuk To: FreeBSD Mailing List References: <8fb087fc-4548-ddbd-ba22-684678c58df8@tundraware.com> Message-ID: Date: Tue, 21 Apr 2020 10:17:54 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: <8fb087fc-4548-ddbd-ba22-684678c58df8@tundraware.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.6.2 (oceanview.tundraware.com [45.55.60.57]); Tue, 21 Apr 2020 10:18:00 -0500 (CDT) X-TundraWare-MailScanner-Information: Please contact the ISP for more information X-TundraWare-MailScanner-ID: 03LFHxdL054244 X-TundraWare-MailScanner: Found to be clean X-TundraWare-MailScanner-SpamCheck: not spam (whitelisted), SpamAssassin (not cached, score=-2.079, required 1, autolearn=not spam, ALL_TRUSTED -1.00, AWL 0.82, BAYES_00 -1.90) X-TundraWare-MailScanner-From: tundra@tundraware.com X-Spam-Status: No X-Rspamd-Queue-Id: 4966dV3w3Gz4Rbd X-Spamd-Bar: - Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=none; spf=pass (mx1.freebsd.org: domain of tundra@tundraware.com designates 45.55.60.57 as permitted sender) smtp.mailfrom=tundra@tundraware.com X-Spamd-Result: default: False [-1.66 / 15.00]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; RCVD_TLS_ALL(0.00)[]; FROM_HAS_DN(0.00)[]; R_SPF_ALLOW(-0.20)[+a]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_GOOD(-0.10)[text/plain]; PREVIOUSLY_DELIVERED(0.00)[freebsd-questions@freebsd.org]; DMARC_NA(0.00)[tundraware.com]; RCPT_COUNT_ONE(0.00)[1]; NEURAL_HAM_LONG(-0.94)[-0.942,0]; IP_SCORE(0.50)[ip: (-1.53), ipnet: 45.55.32.0/19(2.84), asn: 14061(1.24), country: US(-0.05)]; TO_DN_ALL(0.00)[]; NEURAL_HAM_MEDIUM(-0.92)[-0.920,0]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:14061, ipnet:45.55.32.0/19, country:US]; MID_RHS_MATCH_FROM(0.00)[]; SUBJECT_HAS_QUESTION(0.00)[]; RCVD_COUNT_TWO(0.00)[2] X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 21 Apr 2020 15:18:08 -0000 On 4/21/20 8:15 AM, Tim Daneliuk wrote: > On 4/20/20 3:00 PM, Tim Daneliuk wrote: >> Linux and FreeBSD have superframe MTUs of 9000 set MacOS MTU is set to 1500. > > > For anyone else that may run into this: For reasons unclear to me, > FreeBSD hated that the Linux box was forcing an MTU of 9000, even though > FreeBSD had the same thing set. The fix was to tell Linux to use > automatic MTU negotiation and all was well. Interestingly, when I did > this, Linux decide 1500 was the right size and performance came back. > > Go figure... This seems to be a Debian thing only. If I set the MTU to 9000 on a CentOS7 box, it works just fine with FBSD. But two different Debians (raspbian and linuxmint) show severely degraded network performance against FBSD (and only FBSD) when their MTUs are set to 9000. At this point, the problem is fixed, but I would just love for an IP internals expert to explain why this might be happening only viz FreeBSD. -- ---------------------------------------------------------------------------- Tim Daneliuk tundra@tundraware.com PGP Key: http://www.tundraware.com/PGP/