From owner-freebsd-hackers@freebsd.org Sat Dec 1 00:36:38 2018 Return-Path: Delivered-To: freebsd-hackers@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 21D771154B34 for ; Sat, 1 Dec 2018 00:36:38 +0000 (UTC) (envelope-from eugen@grosbein.net) Received: from mailman.ysv.freebsd.org (mailman.ysv.freebsd.org [IPv6:2001:1900:2254:206a::50:5]) by mx1.freebsd.org (Postfix) with ESMTP id 9183D7E9A2 for ; Sat, 1 Dec 2018 00:36:37 +0000 (UTC) (envelope-from eugen@grosbein.net) Received: by mailman.ysv.freebsd.org (Postfix) id 519E81154B31; Sat, 1 Dec 2018 00:36:37 +0000 (UTC) Delivered-To: hackers@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 3FDE01154B30 for ; Sat, 1 Dec 2018 00:36:37 +0000 (UTC) (envelope-from eugen@grosbein.net) Received: from hz.grosbein.net (hz.grosbein.net [IPv6:2a01:4f8:d12:604::2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "hz.grosbein.net", Issuer "hz.grosbein.net" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 3E64D7E998; Sat, 1 Dec 2018 00:36:26 +0000 (UTC) (envelope-from eugen@grosbein.net) Received: from eg.sd.rdtc.ru (eg.sd.rdtc.ru [IPv6:2a03:3100:c:13:0:0:0:5]) by hz.grosbein.net (8.15.2/8.15.2) with ESMTPS id wB10aEs1031429 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sat, 1 Dec 2018 01:36:15 +0100 (CET) (envelope-from eugen@grosbein.net) X-Envelope-From: eugen@grosbein.net X-Envelope-To: ian@freebsd.org Received: from [10.58.0.4] ([10.58.0.4]) by eg.sd.rdtc.ru (8.15.2/8.15.2) with ESMTPS id wB10aDgd009985 (version=TLSv1.2 cipher=DHE-RSA-AES128-SHA bits=128 verify=NOT); Sat, 1 Dec 2018 07:36:13 +0700 (+07) (envelope-from eugen@grosbein.net) Subject: Re: How to use trim command ? To: Ian Lepore , Masachika ISHIZUKA , hackers@freebsd.org References: <20181201.011411.2100982142219259108.ish@amail.plala.or.jp> <7e69211c-6ffb-6155-b17a-a845c0b3586d@grosbein.net> <1543622218.1860.169.camel@freebsd.org> From: Eugene Grosbein Message-ID: Date: Sat, 1 Dec 2018 07:36:01 +0700 User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <1543622218.1860.169.camel@freebsd.org> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=0.3 required=5.0 tests=BAYES_00,LOCAL_FROM,SPF_PASS autolearn=no autolearn_force=no version=3.4.2 X-Spam-Report: * -2.3 BAYES_00 BODY: Bayes spam probability is 0 to 1% * [score: 0.0000] * -0.0 SPF_PASS SPF: sender matches SPF record * 2.6 LOCAL_FROM From my domains X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on hz.grosbein.net X-Rspamd-Queue-Id: 9183D7E9A2 X-Spamd-Result: default: False [-5.29 / 15.00]; ARC_NA(0.00)[]; FORGED_RECIPIENTS_FORWARDING(0.00)[]; RCVD_COUNT_FIVE(0.00)[6]; MX_INVALID(0.50)[cached]; FROM_HAS_DN(0.00)[]; FORWARDED(0.00)[hackers@mailman.ysv.freebsd.org]; TO_DN_SOME(0.00)[]; RCPT_COUNT_THREE(0.00)[3]; MIME_GOOD(-0.10)[text/plain]; DMARC_NA(0.00)[grosbein.net]; NEURAL_HAM_LONG(-1.00)[-1.000,0]; IP_SCORE(-3.60)[ip: (-9.87), ipnet: 2001:1900:2254::/48(-4.63), asn: 10310(-3.43), country: US(-0.09)]; R_SPF_PERMFAIL(0.00)[]; RCVD_IN_DNSWL_MED(-0.20)[5.0.0.0.0.5.0.0.0.0.0.0.0.0.0.0.a.6.0.2.4.5.2.2.0.0.9.1.1.0.0.2.list.dnswl.org : 127.0.9.2]; NEURAL_HAM_SHORT(-0.99)[-0.987,0]; NEURAL_HAM_MEDIUM(-1.00)[-1.000,0]; RCVD_NO_TLS_LAST(0.10)[]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; SUBJECT_ENDS_QUESTION(1.00)[]; ASN(0.00)[asn:10310, ipnet:2001:1900:2254::/48, country:US]; FORGED_RECIPIENTS(0.00)[ian@freebsd.org ..,freebsd-hackers@freebsd.org]; MID_RHS_MATCH_FROM(0.00)[] X-Rspamd-Server: mx1.freebsd.org X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 01 Dec 2018 00:36:38 -0000 01.12.2018 6:56, Ian Lepore wrote: > And therein lies yet another reason why trim is such a horrible name > for this tool: nothing about the word trim implies destroying live > useful information. In idiomatic English, the word drips with overtones > of removing only the unneeded excess from something. That's because it defaults to dry run and its manual pages emphasizes data imminent destruction several times, in bold. newfs destroys data too, cat > /dev/da0 does this too, add the name "dd" itself does not imply data destruction. Can you invent better name? > Truly, dd (with its 30+ years of association of being THE tool that > operates on disk devices or specified sub-ranges of blocks within them) > is the place for such functionality. In fact, I like both. Sometimes it's handy to use dd while dealing with zero blocks inside an image (or /dev/zero) written to single device file. And sometimes it may be useful to be able to "trim /dev/da0 /dev/ada0" with one call.