From owner-freebsd-arm@FreeBSD.ORG Tue May 20 03:36:25 2014 Return-Path: Delivered-To: freebsd-arm@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id BEF7C10D for ; Tue, 20 May 2014 03:36:25 +0000 (UTC) Received: from mail-ee0-x233.google.com (mail-ee0-x233.google.com [IPv6:2a00:1450:4013:c00::233]) (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 50A3425E2 for ; Tue, 20 May 2014 03:36:25 +0000 (UTC) Received: by mail-ee0-f51.google.com with SMTP id e51so73428eek.10 for ; Mon, 19 May 2014 20:36:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-type:content-transfer-encoding; bh=jGPdCx/oaERbRfN+kfnkt4JH6ZLSVzwLHKRHrbBVXJ0=; b=qkZrlVOEaG6/GnurAj/Dta9kaorPUb7bToGqho5CKotmM2GS8awItslDr2p0G8N0yn oEONy0z6i1cLkNAIP0y+3ZVkzXfgFTB+fQ3dbho49+BTMgjIJPUird/7XTV35n5ViWxG JQomJPChxdA6V7A4kVBBqhAyEkXmUTL8xFme2iBqh8fS+ssDmUK5bUt5kHh9njSJO6RY HuQjM7kMzVdkxvAfrjnmnvJBNndP8wJblAL5tutpiaQnZF6YDA7DL95cyRzv4/3nJorr ET8mGkpN8+GwK0ck6tHHAl7uX9ITlzDnkbnDAILaqNsYR2wFfwocOImyASRkXZkWecGB DOVg== X-Received: by 10.14.104.9 with SMTP id h9mr31071185eeg.4.1400556982785; Mon, 19 May 2014 20:36:22 -0700 (PDT) Received: from ketas-laptop.mydomain (ketas-laptop6.si.pri.ee. [2001:ad0:91f:0:21a:6bff:fe66:2ad3]) by mx.google.com with ESMTPSA id x43sm519863eeo.18.2014.05.19.20.36.20 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 19 May 2014 20:36:21 -0700 (PDT) Sender: Sulev-Madis Silber Message-ID: <537ACDB2.9080808@hot.ee> Date: Tue, 20 May 2014 06:36:18 +0300 From: "Sulev-Madis Silber (ketas)" User-Agent: Mozilla/5.0 (X11; FreeBSD i386; rv:15.0) Gecko/20120912 Thunderbird/15.0.1 MIME-Version: 1.0 To: Winston Smith Subject: Re: BBB MMC / SD detection instability with U-Boot 2014.04 (CPU 1GHz) References: <537A050E.3040804@hot.ee> <537AB550.2090401@hot.ee> <537AB675.1020006@hot.ee> <024F43EF-E299-413E-AE42-2507AEDD0886@bsdimp.com> In-Reply-To: X-TagToolbar-Keys: D20140520063618397 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Cc: freebsd-arm X-BeenThere: freebsd-arm@freebsd.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: "Porting FreeBSD to ARM processors." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 20 May 2014 03:36:25 -0000 On 2014-05-20 05:39, Winston Smith wrote: > On Mon, May 19, 2014 at 10:28 PM, Warner Losh wrote: >> Wow! That’s a lot of added 10ms delays… Do we have a theory of the crime >> for why they are needed? Usually they suggest to me that we’re doing something >> wrong (either not checking the right bits in the bridge, having a fixed retry count >> rather than a timed limit and having some bridges fail more slowly than others >> so the delays are effecting the same thing). > > It's a good start (since the BBB is really flakey at 1Ghz), but yes, > more delays aren't good! > > For what it's worth, I'm working in parallel with both FreeBSD and > Debian Wheezy images on the BBB, and it is quite apparent that the BBB > running FreeBSD is *much* slower to boot than the BBB running Debian; > which currently boots to the login prompt in about 15 seconds from > power up. FreeBSD has a 15-20 second delay just to detect the eMMC, > let alone everything else. > > Comparatively, my x64 FreeBSD VM boots much more quickly than my Ubuntu x64 VM. > > -W. > "really flakey" sounds like "unstable, panics 1000 times a day". I don't see any of that here (as of 11.0-CURRENT r266442). Boot, hmm... yea, 1min (just measured) to fully boot up and connect to server (I'm using ethernet, DHCP, loader boot delay = 3, huge Perl program) might be too slow if you have some embedded system which constantly loses power or something... I haven't tried to do any boot time optimizations yet. Compress kernel? Compress userland? Execute something in parallel on init (NOTE: *DON'T* even think about porting Linux init replacements here)? Use rescue-like static binary? Heavily customize / patch kernel? Use own init? Use rootfs inside kernel? Actually I guess many people might think like me... "HELL, optimizing boot time of 1min?! I have more important tasks to do than this".