From owner-svn-src-all@freebsd.org Fri Jan 24 03:32:47 2020 Return-Path: Delivered-To: svn-src-all@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 0700A22CAE7; Fri, 24 Jan 2020 03:32:47 +0000 (UTC) (envelope-from glebius@freebsd.org) Received: from cell.glebi.us (glebi.us [162.251.186.162]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "cell.glebi.us", Issuer "cell.glebi.us" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 483l8G2mM0z4RXd; Fri, 24 Jan 2020 03:32:45 +0000 (UTC) (envelope-from glebius@freebsd.org) Received: from cell.glebi.us (localhost [127.0.0.1]) by cell.glebi.us (8.15.2/8.15.2) with ESMTPS id 00O3WhIG009720 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO); Thu, 23 Jan 2020 19:32:43 -0800 (PST) (envelope-from glebius@freebsd.org) Received: (from glebius@localhost) by cell.glebi.us (8.15.2/8.15.2/Submit) id 00O3Whic009719; Thu, 23 Jan 2020 19:32:43 -0800 (PST) (envelope-from glebius@freebsd.org) X-Authentication-Warning: cell.glebi.us: glebius set sender to glebius@freebsd.org using -f Date: Thu, 23 Jan 2020 19:32:43 -0800 From: Gleb Smirnoff To: Jeff Roberson Cc: Ryan Stone , src-committers , svn-src-all , svn-src-head Subject: Re: svn commit: r357051 - head/sys/dev/bge Message-ID: <20200124033243.GL1268@FreeBSD.org> References: <202001231636.00NGawrr080128@repo.freebsd.org> <20200123230546.GG1268@FreeBSD.org> <20200124012458.GI1268@FreeBSD.org> <20200124024356.GK1268@FreeBSD.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.12.2 (2019-09-21) X-Rspamd-Queue-Id: 483l8G2mM0z4RXd X-Spamd-Bar: - Authentication-Results: mx1.freebsd.org; none X-Spamd-Result: default: False [-1.00 / 15.00]; local_wl_from(0.00)[freebsd.org]; NEURAL_HAM_MEDIUM(-0.87)[-0.865,0]; NEURAL_HAM_LONG(-0.14)[-0.137,0]; ASN(0.00)[asn:27348, ipnet:162.251.186.0/24, country:US] X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 24 Jan 2020 03:32:47 -0000 On Thu, Jan 23, 2020 at 05:09:14PM -1000, Jeff Roberson wrote: J> While we don't have a policy strictly requiring reviews it is the norm to J> have substantial changes socialized and reviewed. I appreciate the work J> that you are doing but it likely should've been discussed somewhere J> more publicly. I apologized if I missed it but I don't see reference to J> anything. That was https://reviews.freebsd.org/D23242 J> Architecturally I am more concerned with the coarseness of net_epoch and J> the duration of hold becoming a resource utilization problem in high J> turn-over workloads. Like short connection tcp. Has anyone done J> substantial testing here? epoch as it is today will hold every free J> callback for a minimum of several clock ticks and a maximum of 2x the J> duration of the longest epoch section time. With preemption, etc. this J> could be 100s of ms of PCBs held. We also are concerned about that theoretically. Haven't yet seen effect in practice, but our sessions are mostly longer living. First we have the tunable to limit batching. Second, there are some ideas on how to improve the garbage collector performance if it becomes an issue. -- Gleb Smirnoff