From owner-freebsd-hackers@FreeBSD.ORG Tue Jan 18 14:05:15 2005 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 68AF216A4CF for ; Tue, 18 Jan 2005 14:05:15 +0000 (GMT) Received: from arginine.spc.org (arginine.spc.org [195.206.69.236]) by mx1.FreeBSD.org (Postfix) with ESMTP id 9A4C643D46 for ; Tue, 18 Jan 2005 14:05:14 +0000 (GMT) (envelope-from bms@spc.org) Received: from localhost (localhost [127.0.0.1]) by arginine.spc.org (Postfix) with ESMTP id AD0F165213; Tue, 18 Jan 2005 14:05:10 +0000 (GMT) Received: from arginine.spc.org ([127.0.0.1]) by localhost (arginine.spc.org [127.0.0.1]) (amavisd-new, port 10024) with LMTP id 98832-03; Tue, 18 Jan 2005 14:05:10 +0000 (GMT) Received: from empiric.dek.spc.org (unknown [62.55.106.225]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by arginine.spc.org (Postfix) with ESMTP id 098B9651EB; Tue, 18 Jan 2005 14:05:10 +0000 (GMT) Received: by empiric.dek.spc.org (Postfix, from userid 1001) id DBB6063A7; Tue, 18 Jan 2005 14:05:23 +0000 (GMT) Date: Tue, 18 Jan 2005 14:05:23 +0000 From: Bruce M Simpson To: - Felix - Message-ID: <20050118140523.GE3054@empiric.icir.org> Mail-Followup-To: - Felix - , freebsd-hackers@freebsd.org References: <002201c4fd4a$c5a81230$0700a8c0@felix> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <002201c4fd4a$c5a81230$0700a8c0@felix> cc: freebsd-hackers@freebsd.org Subject: Re: Kernel mode programming X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 18 Jan 2005 14:05:15 -0000 On Tue, Jan 18, 2005 at 11:45:05AM +0100, - Felix - wrote: > Doing lot of syscalls interrupts in a soft seems to take quite a long time, and seriously slow performances. As far as you can't reduce the syscall amount, is there any way to run apps in kernel mode, in order to call sysfonctions directly ? Perhaps by re-writing softs in kernel modules ? For 95% of applications syscall overhead shouldn't have a major impact on performance. It's difficult to offer any real advice here because you haven't said what the application is, or shown any profiling figures. Maybe you should review your design? Trying to avoid repeating what other posters have said here. BMS