From owner-freebsd-hackers@FreeBSD.ORG Tue Apr 9 00:19:10 2013 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.FreeBSD.org [8.8.178.115]) by hub.freebsd.org (Postfix) with ESMTP id 018F4926 for ; Tue, 9 Apr 2013 00:19:09 +0000 (UTC) (envelope-from erichsfreebsdlist@alogt.com) Received: from alogt.com (alogt.com [69.36.191.58]) by mx1.freebsd.org (Postfix) with ESMTP id C3CCD5EB for ; Tue, 9 Apr 2013 00:19:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=alogt.com; s=default; h=Content-Transfer-Encoding:Content-Type:Mime-Version:References:In-Reply-To:Message-ID:Subject:Cc:To:From:Date; bh=5UsScINwOjb/R9WDjb7MD0rJOouaaEwArrhhePIkx8M=; b=IPKBP3Fr+Q/JqwYfRiXTAW9UPRvPNF9QiQPqvhTYhyR5Q6+4u5Pic4pQB7OSH2+TS6BX5pzFhGTkDvYbHcNdPBb2VmlaD+Lc2k3U5Z/pd3EqLmpxjhwYUSCXhcBGE1voqcsQ/bM8sJiRHfbueelmI2V5p2r1QtvXvCvfYQiCbPU=; Received: from [122.129.203.50] (port=25688 helo=X220.ovitrap.com) by sl-508-2.slc.westdc.net with esmtpsa (SSLv3:DHE-RSA-AES128-SHA:128) (Exim 4.80) (envelope-from ) id 1UPMHE-0039fG-60; Mon, 08 Apr 2013 18:19:08 -0600 Date: Tue, 9 Apr 2013 07:19:04 +0700 From: Erich Dollansky To: Amit Rawat Subject: Re: GSOC 2013 project " Kernel Size Reduction for Embedded System " Message-ID: <20130409071904.5c4dc684@X220.ovitrap.com> In-Reply-To: References: X-Mailer: Claws Mail 3.9.0 (GTK+ 2.24.6; amd64-portbld-freebsd10.0) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - sl-508-2.slc.westdc.net X-AntiAbuse: Original Domain - freebsd.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - alogt.com X-Get-Message-Sender-Via: sl-508-2.slc.westdc.net: authenticated_id: erichsfreebsdlist@alogt.com X-Source: X-Source-Args: X-Source-Dir: Cc: freebsd-hackers@freebsd.org X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 09 Apr 2013 00:19:10 -0000 Hi, On Mon, 8 Apr 2013 20:28:04 +0000 Amit Rawat wrote: > GSOC posted the list of selected organization for GSOC 2013 and I am > highly happy that FreeBSD is among the selected organization. > > I am a third year student interested to work in the field of embedded > system. I applied last year and the title of my project was " Kernel > Size Reduction for Embedded System". The link to my last year > proposal is " > https://www.google-melange.com/gsoc/proposal/review/google/gsoc2012/amitrawat10/1#c8001" > But due to some flaws it doesn't get selected. I am looking to > improve my proposal for this year and apply again. I explain some > portion of my project pictorially on my blog > > " > https://amit10rawat.wordpress.com/2013/02/26/kernel-size-reduction-for-embedded-system/ > " > > I am looking for suggestion and new ideas by which I can reduce the > size of kernel. > did you look at historic operating systems and how they did it? When I was a student, we simply loaded a module into memory and then wrote it to an external memory when not needed. It was a very basic swapping algorithm with fixed size. It did not differentiate between code and data etc. All calls where done through a wrapper which was always in memory. So, the module was loaded by the OS. The OS did not notice that we removed the code from memory. Only the wrapper knew of what we did. We selected functions/modules which have to be in memory and which could be on disk. There was a fixed number of memory segments we could use for loading external modules. The trick was to select the modules so that the system did not lock up. We did not use a tree structure what you might could. The advantage of this was that the actual code was not modified. Yes, I know that this is hard core. My problem would be that I do not know how much effort it would be to implement this in a modern operating system. Erich > Amit Rawat(amraw) > _______________________________________________ > freebsd-hackers@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-hackers > To unsubscribe, send any mail to > "freebsd-hackers-unsubscribe@freebsd.org"