From owner-freebsd-arm@freebsd.org Mon Jan 23 08:02:47 2017 Return-Path: Delivered-To: freebsd-arm@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id A137CCBCCCE for ; Mon, 23 Jan 2017 08:02:47 +0000 (UTC) (envelope-from wlosh@bsdimp.com) Received: from mail-io0-x236.google.com (mail-io0-x236.google.com [IPv6:2607:f8b0:4001:c06::236]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 6B38F7D9 for ; Mon, 23 Jan 2017 08:02:47 +0000 (UTC) (envelope-from wlosh@bsdimp.com) Received: by mail-io0-x236.google.com with SMTP id l66so104650762ioi.1 for ; Mon, 23 Jan 2017 00:02:47 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bsdimp-com.20150623.gappssmtp.com; s=20150623; h=mime-version:sender:in-reply-to:references:from:date:message-id :subject:to:cc; bh=R1ZiBVhAub02oqo/+JI4A1uXv160hG0pcOEVuDr3oFc=; b=tnAEfJKEqtUExvi7mA9+up3hwNZBEysDrtcPSuq0o9BOU9Ub3bctlZBeLu7QU3p7wF W/RP+pNY9oZotZpvCxyxB6zN84mUM0CHAwTS1IPTYN792lYb+qrfnD6ljS/GPlWcxFDp s342bwAoLVHx8qdVyhwO0x407ZaamJaMJ/GqaiICX9YvBnSA/ttUpIHiGJz4Y4gWjggV 126a3qfRNqh57dobAXbhQ39ugvMawB5qgXH2QWiDIKyOhSlg///yFR2spmxbrxVuaYtC 6x3hHr7uCCu5Fkhtklg1L7G5z6rYeYK+r7pJXLQdhuGbDHhU8l3A6PjoIjYyg6MmbMnJ 4y8Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:sender:in-reply-to:references:from :date:message-id:subject:to:cc; bh=R1ZiBVhAub02oqo/+JI4A1uXv160hG0pcOEVuDr3oFc=; b=PB4xGQAXgJkdCJzfR8/xwfOOtaRmVVVYarB+sChbIMDmIFQclHQanb/Q+u2YE43su+ 1b8Pnu2Wu70PDOdje1/nu9f+gg+YyWFXvyp8QMRxShtbYcZtqSLReq2MzoG3NWnhQByh mdiw1H2BwGDe0QKmykmm86nCLt+0PpFCIOH1ZWmfybWaHDdE3q0mg3PqCXxa9HhaGXSW zo9KZxH/PxD29xKAyn43SYoVmD+GP/2f3wY+CPrToeuGJVCrqo3XN/wF6W7TqsnGuYGx hgq9pC5TGDyGuYNGl+OPcrKRcNEf7ZLifZckju9mnrZaniF8x6RbMwsg1wnsK0fODETr vkUA== X-Gm-Message-State: AIkVDXKDB+fHxWcRsum/lsqn/i0p6/twNb3CLZms8gDYTaWZ6VPRVuZr9WnypAIKTxokG0Z0mshf8/1zB5ozSw== X-Received: by 10.107.139.131 with SMTP id n125mr25509754iod.166.1485158566778; Mon, 23 Jan 2017 00:02:46 -0800 (PST) MIME-Version: 1.0 Sender: wlosh@bsdimp.com Received: by 10.79.145.217 with HTTP; Mon, 23 Jan 2017 00:02:46 -0800 (PST) X-Originating-IP: [69.53.245.200] In-Reply-To: References: <201701220253.v0M2rkrl095913@pdx.rh.CN85.dnsmgr.net> From: Warner Losh Date: Mon, 23 Jan 2017 01:02:46 -0700 X-Google-Sender-Auth: T8orVe8R0hNqchMKL19L8bjYB98 Message-ID: Subject: Re: how to measure microsd wear To: tech-lists Cc: "freebsd-arm@freebsd.org" Content-Type: text/plain; charset=UTF-8 X-BeenThere: freebsd-arm@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: "Porting FreeBSD to ARM processors." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 23 Jan 2017 08:02:47 -0000 On Sun, Jan 22, 2017 at 4:55 AM, tech-lists wrote: > On 22/01/2017 02:53, Rodney W. Grimes wrote: >> In either case the manufactures of flash devices have made it very >> clear that these things DO have a write cycle life time, and that >> your going to see a failure eventually if you write enough data to >> them. > > Hi, > > Is there a way one can see how many (or an average) number of write > cycles the cluster or device has had? In order to get a handle on when > it's likely to fail. Or to see what's been remapped and how many more it > can remap? If not on freebsd then on any OS? > > Maybe something that tests # remappable and warns when there's nothing left? > > I mean it's all fair and well the manufacturers saying it will fail on > average after so many writes, but that uncontextualised information is > useless if one cannot establish how many writes have already happened. There's no standard way to get this data. There's several ways to get this data, but it's a terribly gerrymandered, poorly documented landscape at best. Warner