From owner-freebsd-questions Thu Jun 25 07:10:08 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id HAA13124 for freebsd-questions-outgoing; Thu, 25 Jun 1998 07:10:08 -0700 (PDT) (envelope-from owner-freebsd-questions@FreeBSD.ORG) Received: from cygnus.rush.net (root@cygnus.rush.net [209.45.245.133]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id HAA13040 for ; Thu, 25 Jun 1998 07:10:01 -0700 (PDT) (envelope-from lynch@rush.net) Received: from localhost (lynch@localhost) by cygnus.rush.net (8.8.7/8.8.7) with SMTP id KAA28471; Thu, 25 Jun 1998 10:41:46 -0500 (EST) Date: Thu, 25 Jun 1998 10:41:44 -0500 (EST) From: P Lynch To: CyberPeasant cc: GLEN.W.MANN@monsanto.com, freebsd-questions@FreeBSD.ORG Subject: Re: Feasibility as Enterprise Server In-Reply-To: <199806250252.WAA04628@lucy.bedford.net> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG >Glitches in applications or daemons usually don't hose the whole >system. Rebooting should be /rare/. Expect 24/7 operation. Only >P-C OS's are not designed this way. A 16-bit application running >on a default NT system, has access to kernel address space. Shudder. >(Am I right about that? Thought I read that somewhere.) I think >that NT apps by default have access to I/O space. (same question? >Is this true?) I learned more than I wanted to know about NT last week at USENIX. The NT model looks something like this : POSIX subsystem______Win32 Subsystem______Security Subsystem (S Y S T E M S E R V I C E S) (i/o manager)(object manager)(security (process manager)(LPC)(VM)(Graphics) reference manager) M I C R O K E R N E L H A R D W A R E A B S T R A C T I O N L A Y E R the win32 subsystem passes the object to the system services, which then gives it to the I/O manager, passing it to the object manager for handling. The object manager then asks permission for the process to run or the file to be created, THEN passes it to the kernel , back to the I/O manager and to the object manager for final handling. Where code is processed during this and what address space its running in I have no clue, but this may give some idea of how NT works (and probably why its so goddamn slow) ___________________________________________________________________________ Pat Lynch lynch@rush.net Systems Administrator Rush Networking ___________________________________________________________________________ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message