From owner-freebsd-hackers@FreeBSD.ORG Fri Jan 16 21:56:26 2015 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 193DDAB5 for ; Fri, 16 Jan 2015 21:56:26 +0000 (UTC) Received: from mail-ie0-x234.google.com (mail-ie0-x234.google.com [IPv6:2607:f8b0:4001:c03::234]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id D3F135E7 for ; Fri, 16 Jan 2015 21:56:25 +0000 (UTC) Received: by mail-ie0-f180.google.com with SMTP id rp18so23082942iec.11 for ; Fri, 16 Jan 2015 13:56:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:from:date:message-id :subject:to:cc:content-type; bh=2JPjvhLVuwgV6wCPhwFJdN6o2uDuHYYA1VrYNcpnD1k=; b=O7pw78SsA6RIvcI/KSLA2O432eQQlnwD8LC9HF9MbpLJj3FG4bZFm/ncGkjq/z5rdT dkOtqWV3tbgOvulVX9On56TPomXscGnePeRtRs16FsnuwORVf5i/SigNP44uX1myxPu9 zrSIJxOwKPcj4pafiMRu4xVhtVskr8vooGnFAj6FHz5H1SgYmFju1Aq6LTWFvfQYL4oz LYDECbL6pZDPJcsU6qPEM/8PzH/3HV8XBpIwWuzbVusXbPYCXhOlv5pcgLsjat6iF/aP b9yAqCtk5LXLxO5z0qwzhM1R68oX8ybVE/Wv96sISzg0E0N9MqZY0XjO+dDesaiy24s8 jzAw== X-Received: by 10.50.102.4 with SMTP id fk4mr6100561igb.28.1421445385387; Fri, 16 Jan 2015 13:56:25 -0800 (PST) MIME-Version: 1.0 Sender: carpeddiem@gmail.com Received: by 10.107.0.85 with HTTP; Fri, 16 Jan 2015 13:56:04 -0800 (PST) In-Reply-To: <54B927F9.1010401@astart.com> References: <54B7656D.9000704@freebsd.org> <54B927F9.1010401@astart.com> From: Ed Maste Date: Fri, 16 Jan 2015 16:56:04 -0500 X-Google-Sender-Auth: DG1xELFGmMroRTN9ij_sMAFaYH4 Message-ID: Subject: Re: [PATCH] Display progress during getmemsize() so the kernel doesn't look like it hanged To: papowell@astart.com Content-Type: text/plain; charset=UTF-8 Cc: "freebsd-hackers@freebsd.org" X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 16 Jan 2015 21:56:26 -0000 On 16 January 2015 at 10:02, Patrick Powell wrote: > On 01/14/15 22:59, Allan Jude wrote: >> >> Glad to see this, thanks for doing the work Ravi. Also, I agree with jhb@, >> we should disable the test by default in stable/10 (i think it is off by >> default only for VMs currently). > > > Please please do not disable memory tests by default. If you do, when > trying to boot from a CD/Memory Stick > image on a system with bad memory (which would be found by the tests) then > it gets quite difficult to find this > problem. The boot time "memory test" is not particularly valuable, especially on contemporary amd64 hardware. While it won't have any false positives, there are a huge number of failure modes it will not catch. It also does not inform the user of "failure" -- it just removes that memory from the kernel's map. It's really a test of memory presence, not quality.