From nobody Wed Feb 09 12:08:17 2022 X-Original-To: freebsd-net@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id C11A619B0A01; Wed, 9 Feb 2022 12:08:36 +0000 (UTC) (envelope-from hps@selasky.org) Received: from mail.turbocat.net (turbocat.net [IPv6:2a01:4f8:c17:6c4b::2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4JtzDg6Phlz3FZ1; Wed, 9 Feb 2022 12:08:35 +0000 (UTC) (envelope-from hps@selasky.org) Received: from [10.36.2.165] (unknown [178.17.145.105]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mail.turbocat.net (Postfix) with ESMTPSA id 796342600D1; Wed, 9 Feb 2022 13:08:28 +0100 (CET) Message-ID: <3e74ef6a-723c-3ce3-10fb-352faf83ed7a@selasky.org> Date: Wed, 9 Feb 2022 13:08:17 +0100 List-Id: Networking and TCP/IP with FreeBSD List-Archive: https://lists.freebsd.org/archives/freebsd-net List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-net@freebsd.org MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:91.0) Gecko/20100101 Thunderbird/91.5.1 Subject: Re: Receive Side Coalescing(RSC) and LRO Content-Language: en-US To: Wei Hu , "freebsd-hackers@FreeBSD.org" Cc: "freebsd-net@FreeBSD.org" References: <78fb51be-523d-55dd-9648-1ee4431e3861@selasky.org> From: Hans Petter Selasky In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 4JtzDg6Phlz3FZ1 X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=none; spf=pass (mx1.freebsd.org: domain of hps@selasky.org designates 2a01:4f8:c17:6c4b::2 as permitted sender) smtp.mailfrom=hps@selasky.org X-Spamd-Result: default: False [-2.07 / 15.00]; TO_DN_EQ_ADDR_SOME(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; MID_RHS_MATCH_FROM(0.00)[]; RCPT_COUNT_THREE(0.00)[3]; TO_DN_SOME(0.00)[]; R_SPF_ALLOW(-0.20)[+a:mail.turbocat.net]; FROM_HAS_DN(0.00)[]; MIME_GOOD(-0.10)[text/plain]; DMARC_NA(0.00)[selasky.org]; ARC_NA(0.00)[]; NEURAL_SPAM_SHORT(0.23)[0.233]; NEURAL_HAM_LONG(-1.00)[-1.000]; TO_MATCH_ENVRCPT_SOME(0.00)[]; NEURAL_HAM_MEDIUM(-1.00)[-1.000]; MLMMJ_DEST(0.00)[freebsd-hackers,freebsd-net]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:24940, ipnet:2a01:4f8::/32, country:DE]; RCVD_COUNT_TWO(0.00)[2]; RCVD_TLS_ALL(0.00)[] X-ThisMailContainsUnwantedMimeParts: N On 2/9/22 10:28, Wei Hu wrote: > But maybe it is the way to go as FreeBSD lacks system wide support to differentiate hardware and software LRO. Hi Wei, Software LRO has been found superior to hardware LRO, especially when hundreds of connections are involved. The hardware is simply not able keep up. For few connections, hardware LRO may give some performance benefits, but I would rather recommend RoCE/Infiniband for such use-cases, because at the high rates involved, even a single packet loss will cause terrible performance degradation. Personally, I don't see a need for hardware LRO. BTW: kib@ is working on adding more capability bits for ifconfig via nv lists. You might be interested in that: https://reviews.freebsd.org/D32551 --HPS