From owner-freebsd-hackers@FreeBSD.ORG Sat May 31 17:58:10 2008 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 28718106564A for ; Sat, 31 May 2008 17:58:10 +0000 (UTC) (envelope-from tzhuan@gmail.com) Received: from fg-out-1718.google.com (fg-out-1718.google.com [72.14.220.159]) by mx1.freebsd.org (Postfix) with ESMTP id 8CBFE8FC17 for ; Sat, 31 May 2008 17:58:09 +0000 (UTC) (envelope-from tzhuan@gmail.com) Received: by fg-out-1718.google.com with SMTP id l26so414049fgb.35 for ; Sat, 31 May 2008 10:58:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:sender:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references:x-google-sender-auth; bh=HnfFvco83XB3H9FKrfArIgrbDkIrdK/ws6OeQj+cZxM=; b=xYQe0vyV/6vYUugPkrSUjbE7a9SUaWSOp4/7U8MuP8pdnBmAUX79bWRkBO9qyZVGht5GiVxj4eZ1Zy9Ei3B5WqQKXaR+K5W+VQSxlcnqEV6m1P7xWxANE14JgSH0ySvZKOxTKC446tD7mP003csSZJNQ+yjxO4RsU0NoQ2DgPTk= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:sender:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references:x-google-sender-auth; b=IlAQyij1DIcPNXfahioQBgwqtdAecn2bS3bHeTJBWLODvEDKJzcSkSagg4iCZ/9yM+QGE8ZS6izK0Z+FPRml2rm2yDuYV1PQEel65qa+1vlcuyhznTIsGtoj5aPAzHD1IaWNLYGaivU5ydaZA5zSxkW003lHwGF/nrJyO8nzGXQ= Received: by 10.86.76.20 with SMTP id y20mr685654fga.5.1212256686503; Sat, 31 May 2008 10:58:06 -0700 (PDT) Received: by 10.86.92.1 with HTTP; Sat, 31 May 2008 10:58:06 -0700 (PDT) Message-ID: <6a7033710805311058t41ef1ffah97648975f842846d@mail.gmail.com> Date: Sun, 1 Jun 2008 01:58:06 +0800 From: "Tz-Huan Huang" Sender: tzhuan@gmail.com To: "John Baldwin" In-Reply-To: <200805311249.53986.jhb@freebsd.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <6a7033710805302252v43a7b240x66ca3f5e3dd5fda4@mail.gmail.com> <200805311249.53986.jhb@freebsd.org> X-Google-Sender-Auth: 4a8bde6555d7297f Cc: freebsd-hackers@freebsd.org Subject: Re: Is there any way to increase the KVM? X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 31 May 2008 17:58:10 -0000 On Sun, Jun 1, 2008 at 12:49 AM, John Baldwin wrote: > On Saturday 31 May 2008 01:52:56 am Tz-Huan Huang wrote: >> Hi, >> >> Our nfs server is running 7-stable/amd64 with 8G ram, the size of zfs >> pool is 12T. We have set vm.kmem_size and vm.kmem_size_max to >> 1.5G, but the kernel still panics by "kmem_map too small" often. >> According to [1], the limitation is not only by the loader (is it fixed >> now?) but also by the default layout of KVM. [2] points a way to increase >> the KVM, but we get the similar linking error. >> >> Is there any standard way to modify the layout of KVM? For example, we >> may want to set KVM to 6G and leave the 2G for user space usage. > > On i386 you only have 4GB of virtual address space period. For amd64 you can > jack up KVM just fine AFAIK. The mcmodel=kernel stuff should only affect > global variables (so .data and .bss) and not malloc'd stuff. Have you tried > increasing the KVM size and seeing what happens? Actaully I have no idea how to increase the KVM size ... Should I change some knobs on kernel conifg or some codes? When setting the vm.kmem_size to almost or more than 2G, the kernel panics immediately after booting. When I change the KPDPI like [1], I have linking error. Thanks, Tz-Huan [1] http://lists.freebsd.org/pipermail/freebsd-current/2008-March/084325.html