From owner-freebsd-stable@freebsd.org Tue Jan 30 14:09:48 2018 Return-Path: Delivered-To: freebsd-stable@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 20823ECC6E5 for ; Tue, 30 Jan 2018 14:09:48 +0000 (UTC) (envelope-from asomers@gmail.com) Received: from mail-lf0-x235.google.com (mail-lf0-x235.google.com [IPv6:2a00:1450:4010:c07::235]) (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 7CA526E06B; Tue, 30 Jan 2018 14:09:47 +0000 (UTC) (envelope-from asomers@gmail.com) Received: by mail-lf0-x235.google.com with SMTP id t79so15542182lfe.3; Tue, 30 Jan 2018 06:09:47 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:sender:in-reply-to:references:from:date:message-id :subject:to:cc; bh=wuwaQ1H1EnycfXCkceomtW0yy5OUW5+LJ8KJPOdmVVE=; b=jL+rGZcNrwmc9HOGIRYs1bVnAf/a/ldN6jlzMfyprUpELChtk0j98tSboPqGc47Jb1 W3feYNo4SzJDXzZzINTLskRUNbp4C7W6BEU+VGJq4JTIiZh7WuWVaad8Wrl7o5WMNJWv m8JaLsdy66hUTSvTOFd2MnQ1SueR3s87/WitgIpnNGH/ViFdsBa+6QQtoqMg1WMfjrQI /YERomMHK3SHIRHC1EPL+AaZDYy7aYBT7EXQrLmzsnl8q5KNVAPkYOXFf3QTCB1y8tMb IAuIECadVyB8YBNplszzCP2AQW6rgkAsHXHspV9QOC1+891jYUihAt5VBVX+Bppa8RbD SDEQ== 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=wuwaQ1H1EnycfXCkceomtW0yy5OUW5+LJ8KJPOdmVVE=; b=f5/2FACFIqXYoLmlnS/ZAPobWm+/azfeRaJD+5dYkzksjdWBe4nz+vDuDS6LWkurBY w9lkTk42QRINxKed7ya9FMlH4DkjmoHCk3RKw+DBEOy6Pi7RHmTbTY0cv+8mu1eurhS5 7RFkaiR7UHK2kW/oGa5OECeGCBub3rD3c7c5McQ5Tww8fKnFbj9iQOfnVN2CNVZL1pjG eeAInWT55rXy7p6DCc3O5nwxLmih6zCeoEr5OxTqymB2RDbs+L/4SgfWenxFhc8rwMs+ 6GePOKYiLt096s1DnLzuITTy34jVuqG075P0Etu4hTFFuAObYIdbj+iXiSJ3PV3WB4s4 rdGw== X-Gm-Message-State: AKwxyteUIKNAQjgJb2GQ9r2jzqYYGqJAoYns1j8pW4Up4BdeVr8QtZDM bQM0mx0mqRp1CclRypByK0rHM7EptLBtP0WnvfE= X-Google-Smtp-Source: AH8x226QBr7gLDCG6I8Yu6xk8024fVEAxby5nDRNdlMmE/tZPffOUSDrxGzoFDGHskQnLh0lZsGOeClEp8kFo71D470= X-Received: by 10.46.115.9 with SMTP id o9mr4863224ljc.89.1517321385078; Tue, 30 Jan 2018 06:09:45 -0800 (PST) MIME-Version: 1.0 Sender: asomers@gmail.com Received: by 10.179.87.131 with HTTP; Tue, 30 Jan 2018 06:09:44 -0800 (PST) In-Reply-To: <20180130071123.GB43715@bali> References: <201801281632.w0SGWiui055204@mail.karels.net> <20180130071123.GB43715@bali> From: Alan Somers Date: Tue, 30 Jan 2018 07:09:44 -0700 X-Google-Sender-Auth: 5dwAOg0ewoyFBATL6IauwoevyhQ Message-ID: Subject: Re: i386 with 4GB RAM: less than 2GB available on A2SAV (Intel Atom E3940) To: Andre Albsmeier Cc: Mike Karels , FreeBSD , Dimitry Andric Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.25 X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 30 Jan 2018 14:09:48 -0000 On Tue, Jan 30, 2018 at 12:11 AM, Andre Albsmeier < Andre.Albsmeier@siemens.com> wrote: > On Sun, 28-Jan-2018 at 10:32:44 -0600, Mike Karels wrote: > > > On 28 Jan 2018, at 15:57, Andre Albsmeier > = > > > wrote: > > > > I have a lot of machines running with 4 GB physical RAM and, for > > > > some reasons, I still have to use a 32 bits OS. > > > >=20 > > > > All of them show something between 3 and 3.5 GB of RAM available > > > > in dmesg but the brand new Supermicro A2SAV really shocked me: > > > >=20 > > > > FreeBSD 11.1-STABLE #0: Mon Jan 15 06:57:10 CET 2018 > > > > ... > > > > real memory =3D 4294967296 (4096 MB) > > > > avail memory =3D 1939558400 (1849 MB) > > > > ... > > > >=20 > > > > So do people have any ideas how I might get a bit closer to at least > > > > 3 GB? I assume there are no FreeBSD knobs which might help but hope > > > > dies last... > > > > > This is a common problem on i386. Most likely some ranges are reserved > > > for I/O mappings, such as video cards. If you boot with -v, I think > the > > > kernel prints an overview of the physical ram chunks available? I > don't > > > know of any other way to get such an overview. > > > > > Another option is to try PAE, but I have no idea how stable that is... > > > > > -Dimitry > > > > I suspect that the unavailable RAM has been mapped above 4 GB by the > BIOS. > > > > About PAE: at $JOB, we have a FreeBSD 8.2 system that has been running > > PAE reliably since 8.2 was new. Also, we ship amd64 systems that run > > mostly 32-bit binaries, which works well. > > But can the entire userland be 32 bit only? > Sure. I do this with jails. It's no problem to have a 32-bit jail on a 64-bit kernel. Kernel modules would be an issue, though. If you need any, you'll have to find a way for the 64-bit machines to find 64-bit kernel modules. > > Maybe I'll try the PAE thing... >