From nobody Fri Sep 30 11:34:45 2022 X-Original-To: freebsd-hackers@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 4Mf7T708pKz4df6Y for ; Fri, 30 Sep 2022 11:35:39 +0000 (UTC) (envelope-from darius@dons.net.au) Received: from midget.dons.net.au (2403-5800-5200-4700-225-90ff-fe47-39b4.ip6.aussiebb.net [IPv6:2403:5800:5200:4700:225:90ff:fe47:39b4]) (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 ECDSA (P-384) client-digest SHA384) (Client CN "dons.net.au", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4Mf7T453NXz3TNM for ; Fri, 30 Sep 2022 11:35:35 +0000 (UTC) (envelope-from darius@dons.net.au) Received: from midget.dons.net.au (localhost [127.0.0.1]) by midget.dons.net.au (8.17.1/8.16.1) with ESMTPS id 28UBZ0Wf087110 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO) for ; Fri, 30 Sep 2022 21:05:00 +0930 (ACST) (envelope-from darius@dons.net.au) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=dons.net.au; s=default; t=1664537705; bh=rLQes1qiKEKJg0NSA2hpudN11Aej+xapuFugyjgENLM=; h=Subject:From:In-Reply-To:Date:Cc:References:To; b=BtVt7aYhZZmLoyJJo058cN5JCv/CDNE8PMTiaOaOUcpUIBs2z/FdWoXyCg+tMcUIc lC26DLJtpkGPbk4H+eFhp0/7XArB2rGEtdwjp487BEwR5zE5K9UmNVZ+TODBxtRYha WX28vG/70tNRwy5pge+N3HNUA/3/ALvA5KQ+imYo= Received: (from mailnull@localhost) by midget.dons.net.au (8.17.1/8.16.1/Submit) id 28UBYrw2087080 for ; Fri, 30 Sep 2022 21:04:53 +0930 (ACST) (envelope-from darius@dons.net.au) X-MIMEDefang-Relay-a1a524833438212bf543e143edafb27bc4d2c346: 2403:5800:5200:4700:3928:39c3:614e:a9b Received: from smtpclient.apple ([IPv6:2403:5800:5200:4700:3928:39c3:614e:a9b] [2403:5800:5200:4700:3928:39c3:614e:a9b]) by 2403-5800-5200-4700-225-90ff-fe47-39b4.ip6.aussiebb.net (envelope-sender ) (MIMEDefang) with ESMTP id 28UBYra3087071; Fri, 30 Sep 2022 21:04:53 +0930 Content-Type: text/plain; charset=us-ascii List-Id: Technical discussions relating to FreeBSD List-Archive: https://lists.freebsd.org/archives/freebsd-hackers List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-hackers@freebsd.org Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3696.120.41.1.1\)) Subject: Re: Block sizes for dd(1) to USB memory sticks (flash drives) for installers for FreeBSD From: "Daniel O'Connor" In-Reply-To: <1cede94a-c114-17fa-a81c-bb58c2b5879c@freebsd.org> Date: Fri, 30 Sep 2022 21:04:45 +0930 Cc: freebsd-hackers@freebsd.org Content-Transfer-Encoding: quoted-printable Message-Id: <4C0C2819-439C-448F-A576-A63AEBD45F5F@dons.net.au> References: <1cede94a-c114-17fa-a81c-bb58c2b5879c@freebsd.org> To: Graham Perrin X-Mailer: Apple Mail (2.3696.120.41.1.1) X-Spam-Score: 1.3 (*) No, score=1.3 required=5.0 tests=RDNS_NONE,SPF_HELO_NONE, T_SPF_PERMERROR autolearn=no autolearn_force=no version=3.4.5 X-Scanned-By: MIMEDefang 2.84 on 10.0.2.1 X-Rspamd-Queue-Id: 4Mf7T453NXz3TNM X-Spamd-Bar: --- Authentication-Results: mx1.freebsd.org; dkim=pass header.d=dons.net.au header.s=default header.b=BtVt7aYh; dmarc=pass (policy=quarantine) header.from=dons.net.au; spf=pass (mx1.freebsd.org: domain of darius@dons.net.au designates 2403:5800:5200:4700:225:90ff:fe47:39b4 as permitted sender) smtp.mailfrom=darius@dons.net.au X-Spamd-Result: default: False [-3.50 / 15.00]; NEURAL_HAM_MEDIUM(-1.00)[-1.000]; NEURAL_HAM_LONG(-1.00)[-1.000]; NEURAL_HAM_SHORT(-1.00)[-1.000]; DMARC_POLICY_ALLOW(-0.50)[dons.net.au,quarantine]; MV_CASE(0.50)[]; R_SPF_ALLOW(-0.20)[+mx]; R_DKIM_ALLOW(-0.20)[dons.net.au:s=default]; MIME_GOOD(-0.10)[text/plain]; MLMMJ_DEST(0.00)[freebsd-hackers@freebsd.org]; ARC_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; FROM_EQ_ENVFROM(0.00)[]; RCVD_TLS_LAST(0.00)[]; RCPT_COUNT_TWO(0.00)[2]; RCVD_COUNT_THREE(0.00)[4]; TO_MATCH_ENVRCPT_SOME(0.00)[]; FROM_HAS_DN(0.00)[]; DKIM_TRACE(0.00)[dons.net.au:+]; TO_DN_SOME(0.00)[]; ASN(0.00)[asn:4764, ipnet:2403:5800::/32, country:AU]; PREVIOUSLY_DELIVERED(0.00)[freebsd-hackers@freebsd.org]; MID_RHS_MATCH_FROM(0.00)[] X-ThisMailContainsUnwantedMimeParts: N > On 30 Sep 2022, at 16:56, Graham Perrin = wrote: > and = elsewhere: >=20 > bs=3D1m >=20 > Why so small? >=20 > I find things much faster with a larger block size. Is this my = imagination? 1m seems large and I wouldn't have expected much improvement past, say.. = 128k. What sort of improvements do you see? ISTR when I have looked before it wasn't much better than 16k. Since it's conv=3Dsync I think you can crank up the size as much as you = like without a problem though (unless your destination device is close = to the image size in which case the padding might make it appear to = fail) -- Daniel O'Connor "The nice thing about standards is that there are so many of them to choose from." -- Andrew Tanenbaum