From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.33) id 1C0Ghz-0001TX-HS for qemu-devel@nongnu.org; Thu, 26 Aug 2004 05:38:15 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.33) id 1C0Ghx-0001T2-UN for qemu-devel@nongnu.org; Thu, 26 Aug 2004 05:38:14 -0400 Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.33) id 1C0Ghw-0001Sr-P4 for qemu-devel@nongnu.org; Thu, 26 Aug 2004 05:38:13 -0400 Received: from [216.254.0.202] (helo=mail2.speakeasy.net) by monty-python.gnu.org with esmtp (TLSv1:DES-CBC3-SHA:168) (Exim 4.34) id 1C0GdG-0004dw-Ep for qemu-devel@nongnu.org; Thu, 26 Aug 2004 05:33:22 -0400 Received: from dsl081-088-222.lax1.dsl.speakeasy.net (HELO [192.168.111.2]) ([64.81.88.222]) (envelope-sender ) by mail2.speakeasy.net (qmail-ldap-1.03) with SMTP for ; 26 Aug 2004 09:33:20 -0000 Subject: Re: [Qemu-devel] QEMU with KNOPPIX From: "John R. Hogerhuis" In-Reply-To: <20040826.165738.48522976.k.suzaki@aist.go.jp> References: <1093428159.16123.737.camel@aragorn> <20040826.141903.78715588.k.suzaki@aist.go.jp> <1093500780.21464.780.camel@aragorn> <20040826.165738.48522976.k.suzaki@aist.go.jp> Content-Type: text/plain Message-Id: <1093512840.27729.849.camel@aragorn> Mime-Version: 1.0 Date: Thu, 26 Aug 2004 02:34:00 -0700 Content-Transfer-Encoding: 7bit Reply-To: jhoger@pobox.com, qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org On Thu, 2004-08-26 at 00:57, Kuniyasu Suzaki wrote: > Yes, root File System of KNOPPIX is stored to a compressed loop-back > device. It is called "CLOOP". KNOPPIX has boot option to move CLOOP file > to hard disk or RAM disk. It takes time to boot, but response makes > better. > > But I think the option is not valuable on QEMU. It makes slow boot on QEMU. > To make short-cut of boot is most important. > How long does it take to transfer the CLOOP file to hard disk? I would think that you could do it just once, say and drop it in My Documents, or wherever the user wants, with a pointer to the file in the registry. Don't have the virtual machine do it (that's slow), have the script that starts QEMU copy the file to the host's hard disk before running QEMU. Also put a version number there. Then read some version number off the Knoppix disk... if they match, and the file is already on the hard drive don't copy it again. So you get a one-time hit, for hopefully a big performance gain and the user won't see it again until a new version of knoppix-qemu-win comes out (BTW, what is a good name for this? kqw? something short... I actually registered a domain when I thought of this possibility sometime back, "linsitu" if that makes any sense to anyone...) Might be a cool, general way to do this transparently in QEMU. What if there was a option/feature in QEMU, that as it reads from a CD-ROM, it builds a cache of it on the hard disk. Maybe it saves some unique info from cd, and the hash for some random blocks. Then when QEMU is started again with the same disk, it hashes those blocks and decides whether it already has cached any/all of that cd on hard disk. If it has it reads from cache of that cd on hard disk. Then you would have something that could work with any bootable linux cd without any tweaking. But booting a suspended image will probably save a lot of time so either one is worth some focus. I don't think the QEMU engine itself is off the hook either. There are definitely things that could be squeezed there, the question is, is there any low-hanging fruit which would provide a measurable performance gain... -- John.