From owner-freebsd-fs@freebsd.org Sat Sep 8 08:36:41 2018 Return-Path: Delivered-To: freebsd-fs@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 6BB97FECE6C for ; Sat, 8 Sep 2018 08:36:41 +0000 (UTC) (envelope-from marklmi@yahoo.com) Received: from sonic317-22.consmr.mail.gq1.yahoo.com (sonic317-22.consmr.mail.gq1.yahoo.com [98.137.66.148]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id D144E8BE1B for ; Sat, 8 Sep 2018 08:36:40 +0000 (UTC) (envelope-from marklmi@yahoo.com) X-YMail-OSG: 5a72AzQVM1mY1EHh47knjCkETWPxu4vojb.IdwOblaYEBoqRvE24OZW9d3OhUnK q5yw0f4iKGvFPhW49zOe_7OCsxv24xZl0jLUEE3F1P9irfveYxgDGSQPWVuS_LSSi33F1PmvYNrz UoNvmAJCGYNN90u4WEz4o8KQlHD.AtGKLNkt0Qv3CUYOgvBJDX3YQT_o_alSuqQ9gABKrK2GXAWJ ydFoci707ktKjZPEM3PXAGp0kd85Eqait7LTi5E.TJnXUy1yAyQw4EMR7v6Tf_giy0WOdb3FEqO. TiizWx7b.p7pp89c5uIGlKW0HglHCjpDGtlfHdl3uI4H_PaBf8y3tE1HLKdT1RFHcCmpRaMrwAch c.Neuosa7p3fPmEdvX3re0mnP0uFGYLcYQ84xy75BusEpo5weJI4Tb7PC6d9HsIVMp5vptbGz5hY oCuDtfi1YF5.AtW9LIGgmYUFsfYRCW88TckSPYxoZwddXKEiyxa14oGxBPuhGmJPz1zPqAuFv_qZ 8CzJD8jXVAl65ojCtak9UfuDcrrdgKCLa_qasDF2DNK3enL5.fi3JHNtmi40n6e0pwll0pD_yNtW 2M9adOR25doP__OYhwEi9aJzrvKbFZNgWxEMJzxUsGVhXXUMkRazz0NxR_xqZE0IVUCVV6v7b42. QzGycvZzNANVEdjhBe8lascMEvpr8Jyf7Igne0nCr2bcRC.as291Zgzw94Px3yWF7Vqacm7IObcd 31rCM47RT.mgpG4Aim0394jFP7evz_bZZ1V0qfXC2lphsa3pMPaAIwoM1IZumhoVwiH6KIPlVsuK QGJv2_rRKy6uRwDIn6YxBo9J1E5pYNBnZAWsC2WNwKkiIoygEYJeq2Ew7_OVvCDaJwx09YLFxwmT LCFI39DLrhFapa8uonLMYuYIY7_xT04SatpcjbPwhFKEO9ZZLhQ44H4UR5U1eDlkyPjBVjgDe0zA A2t3rHNQIH_Vi.R6G4ptI1saU2EanCTXmtzvVExEo1fvlFgrSrktNcAKf1GIQJSbOkKDmgQ.hoyu b.mM23kQs Received: from sonic.gate.mail.ne1.yahoo.com by sonic317.consmr.mail.gq1.yahoo.com with HTTP; Sat, 8 Sep 2018 08:36:32 +0000 Received: from ip70-189-131-151.lv.lv.cox.net (EHLO [192.168.0.105]) ([70.189.131.151]) by smtp432.mail.gq1.yahoo.com (Oath Hermes SMTP Server) with ESMTPA ID 4d42ee13eaaca40bf2a446cbb7ff4597; Sat, 08 Sep 2018 08:36:30 +0000 (UTC) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 11.5 \(3445.9.1\)) Subject: Re: CFT: TRIM Consolodation on UFS/FFS filesystems From: Mark Millard In-Reply-To: Date: Sat, 8 Sep 2018 01:36:29 -0700 Cc: bob prohaska , FreeBSD Filesystems Content-Transfer-Encoding: 7bit Message-Id: References: <201809062330.w86NUphJ027262@chez.mckusick.com> To: Kirk McKusick X-Mailer: Apple Mail (2.3445.9.1) X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.27 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 08 Sep 2018 08:36:41 -0000 Just an FYI. I figured out a hack that allows the e.MMC on a microsd card adapter to be used to boot and operate the Pine64+ 2GB, in DDR52 mode at that. (And so shows what was missing in the FreeBSD operation even if the code change is not the proper form of an official fix.) But in the process I discovered that FreeBSD is using (for e.MMC in this tested context): mmc0: REQUEST: CMD38 arg 0x1 flags 0x1d That "0x1" means: TRIM that forces reads of zeros: the true Data Removal command for mmc protocol, a form of erase. 0x3 would be DISCARD, the "performance command" that does not guarantee what would be read afterwards: no erase required. TRIM is older (added in e/MCC 4.4). DISCARD is newer (added in e.MMC 4.5). Each is mandatory when the version has the function at all. Does FreeBSD have a policy of preferring erasure when there is also the option to not require it? === Mark Millard marklmi at yahoo.com ( dsl-only.net went away in early 2018-Mar)