From owner-svn-src-all@freebsd.org Fri Jan 17 11:21:55 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 CA24022B37C for ; Fri, 17 Jan 2020 11:21:55 +0000 (UTC) (envelope-from slw@zxy.spb.ru) Received: from zxy.spb.ru (zxy.spb.ru [195.70.199.98]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 47zdtp7415z4Njr; Fri, 17 Jan 2020 11:21:54 +0000 (UTC) (envelope-from slw@zxy.spb.ru) Received: from slw by zxy.spb.ru with local (Exim 4.86 (FreeBSD)) (envelope-from ) id 1isPhH-0003w8-6w; Fri, 17 Jan 2020 14:21:51 +0300 Date: Fri, 17 Jan 2020 14:21:51 +0300 From: Slawa Olhovchenkov To: Eugene Grosbein Cc: Ed Maste , "svn-src-all@freebsd.org" , Oliver Pinter , Nathan Whitehorn , Ben Woods , Warner Losh Subject: Re: svn commit: r356758 - in head/usr.sbin/bsdinstall: . scripts Message-ID: <20200117112151.GJ38096@zxy.spb.ru> References: <202001150747.00F7lqiG071097@repo.freebsd.org> <20200117000333.GI38096@zxy.spb.ru> <3b4b4bda-75a3-3019-bc02-ecd6acacd77f@grosbein.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3b4b4bda-75a3-3019-bc02-ecd6acacd77f@grosbein.net> User-Agent: Mutt/1.5.24 (2015-08-30) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: slw@zxy.spb.ru X-SA-Exim-Scanned: No (on zxy.spb.ru); SAEximRunCond expanded to false X-Rspamd-Queue-Id: 47zdtp7415z4Njr X-Spamd-Bar: ++ Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=none; spf=none (mx1.freebsd.org: domain of slw@zxy.spb.ru has no SPF policy when checking 195.70.199.98) smtp.mailfrom=slw@zxy.spb.ru X-Spamd-Result: default: False [2.63 / 15.00]; ARC_NA(0.00)[]; TO_DN_EQ_ADDR_SOME(0.00)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; IP_SCORE(0.09)[asn: 5495(0.42), country: RU(0.01)]; TAGGED_RCPT(0.00)[]; MIME_GOOD(-0.10)[text/plain]; DMARC_NA(0.00)[zxy.spb.ru]; AUTH_NA(1.00)[]; NEURAL_SPAM_MEDIUM(0.66)[0.662,0]; TO_MATCH_ENVRCPT_SOME(0.00)[]; NEURAL_SPAM_LONG(0.98)[0.978,0]; RCPT_COUNT_SEVEN(0.00)[7]; R_SPF_NA(0.00)[]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:5495, ipnet:195.70.192.0/19, country:RU]; MID_RHS_MATCH_FROM(0.00)[]; RCVD_TLS_LAST(0.00)[]; RCVD_COUNT_TWO(0.00)[2] 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, 17 Jan 2020 11:21:55 -0000 On Fri, Jan 17, 2020 at 12:12:22PM +0700, Eugene Grosbein wrote: > 17.01.2020 7:03, Slawa Olhovchenkov write: > > >>>> There are multiple scenarios there ZFS may be sub-optimal at least: small i386 virtual guests > >>>> or 32-bit only hardware like AMD Geode, or big amd64 SSD-only systems with bhyve and multiple guests > >>>> that need lots of memory and should not fight with ZFS for RAM etc. > >>> > >>> That may well be the case, but our defaults should represent the > >>> configuration that's desirable to the largest set of users, and IMO > >>> that's ZFS in most cases today. > >>> > >>> It might be that we should default to UFS on i386 and ZFS on amd64? > >> > >> UFS may be better for any virtual guest having RAM less or equal to 4GB. > > > > Why? > > Considering /usr/ports, /usr/src and /usr/obj and amount of RAM > needed to keep metadata in ZFS ARC /usr/ports, /usr/src and /usr/obj don't need be exist on low-RAM install -- use poudriere and release build on dedicated build host and applay binary update. > plus standard daily periodic scripts traveling filesystems, low-RAM virtual machine utilizing its RAM to full amount > can work reliably with UFS and hang at nights due to extra ZFS overhead in default install (not tuned). Just need fix ZFS ARC pressure and UMA zone reclaim. ZFS ARC overhead about 10-20MB (IMHO) on low-RAM install. This is negligible from 512MB.