From nobody Wed Jan 12 19:35:19 2022 X-Original-To: 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 B619F1947E6B for ; Wed, 12 Jan 2022 19:35:22 +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) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 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 4JYyT56XqVz4sJP for ; Wed, 12 Jan 2022 19:35:21 +0000 (UTC) (envelope-from glebius@freebsd.org) Received: from cell.glebi.us (localhost [127.0.0.1]) by cell.glebi.us (8.16.1/8.16.1) with ESMTPS id 20CJZJNe068381 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO) for ; Wed, 12 Jan 2022 11:35:20 -0800 (PST) (envelope-from glebius@freebsd.org) Received: (from glebius@localhost) by cell.glebi.us (8.16.1/8.16.1/Submit) id 20CJZJlf068380 for net@freebsd.org; Wed, 12 Jan 2022 11:35:19 -0800 (PST) (envelope-from glebius@freebsd.org) X-Authentication-Warning: cell.glebi.us: glebius set sender to glebius@freebsd.org using -f Date: Wed, 12 Jan 2022 11:35:19 -0800 From: Gleb Smirnoff To: net@freebsd.org Subject: Re: compressed TIME-WAIT to be decomissioned Message-ID: References: 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 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: 4JYyT56XqVz4sJP X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=none; spf=softfail (mx1.freebsd.org: 162.251.186.162 is neither permitted nor denied by domain of glebius@freebsd.org) smtp.mailfrom=glebius@freebsd.org X-Spamd-Result: default: False [-2.33 / 15.00]; HAS_XAW(0.00)[]; TO_DN_NONE(0.00)[]; R_SPF_SOFTFAIL(0.00)[~all]; NEURAL_HAM_SHORT(-0.24)[-0.237]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:27348, ipnet:162.251.186.0/24, country:US]; MID_RHS_MATCH_FROM(0.00)[]; TO_DOM_EQ_FROM_DOM(0.00)[]; ARC_NA(0.00)[]; NEURAL_HAM_MEDIUM(-1.00)[-0.996]; FREEFALL_USER(0.00)[glebius]; FROM_HAS_DN(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; NEURAL_HAM_LONG(-1.00)[-0.997]; MIME_GOOD(-0.10)[text/plain]; PREVIOUSLY_DELIVERED(0.00)[net@freebsd.org]; DMARC_NA(0.00)[freebsd.org]; RCPT_COUNT_ONE(0.00)[1]; RCVD_COUNT_TWO(0.00)[2]; RCVD_TLS_ALL(0.00)[] X-ThisMailContainsUnwantedMimeParts: N On Wed, Jan 12, 2022 at 10:48:59AM -0800, Gleb Smirnoff wrote: T> * Many of HTTP connections were made by older browsers, which were not able T> to use persistent HTTP connections. Those browsers that could, would T> recycle connections more often, then today. Default timeouts in Apache T> for persistent connections were short. So, the ratio of connections T> in TIME-WAIT compared to live connections was much bigger than today. T> Here is sample data from 2008 provided to me by Igor Sysoev: T> T> ITEM SIZE LIMIT USED FREE REQUESTS FAILURES T> tcpcb: 728, 163840, 22938, 72722, 13029632, 0 T> tcptw: 88, 163842, 10253, 72949, 2447928, 0 T> T> We see that TIME-WAITs are ~ 50% of live connections. T> T> Today I see that TIME-WAITs are ~ 1% of connections. My data is biased T> here, since I'm looking at servers that do mostly video streaming. I'd T> be grateful if anybody replies to this email with some other modern data T> on ratio between tcpcb and tcptw allocations. Yes, my data was quite biased. I found evidence that for smaller assets served by HTTP the ratio of tcptw/tcpcb can be up to 35% these days. -- Gleb Smirnoff