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\documentclass[11pt,twoside,final,openright]{report}
\usepackage{a4,graphicx,html,setspace,times}
\usepackage{comment,parskip}
\setstretch{1.15}
\begin{document}
% TITLE PAGE
\pagestyle{empty}
\begin{center}
\vspace*{\fill}
\includegraphics{figs/xenlogo.eps}
\vfill
\vfill
\vfill
\begin{tabular}{l}
{\Huge \bf Interface manual} \\[4mm]
{\huge Xen v2.0 for x86} \\[80mm]
{\Large Xen is Copyright (c) 2002-2004, The Xen Team} \\[3mm]
{\Large University of Cambridge, UK} \\[20mm]
\end{tabular}
\end{center}
{\bf
DISCLAIMER: This documentation is currently under active development
and as such there may be mistakes and omissions --- watch out for
these and please report any you find to the developer's mailing list.
Contributions of material, suggestions and corrections are welcome.
}
\vfill
\cleardoublepage
% TABLE OF CONTENTS
\pagestyle{plain}
\pagenumbering{roman}
{ \parskip 0pt plus 1pt
\tableofcontents }
\cleardoublepage
% PREPARE FOR MAIN TEXT
\pagenumbering{arabic}
\raggedbottom
\widowpenalty=10000
\clubpenalty=10000
\parindent=0pt
\parskip=5pt
\renewcommand{\topfraction}{.8}
\renewcommand{\bottomfraction}{.8}
\renewcommand{\textfraction}{.2}
\renewcommand{\floatpagefraction}{.8}
\setstretch{1.1}
\chapter{Introduction}
Xen allows the hardware resources of a machine to be virtualized and
dynamically partitioned, allowing multiple different {\em guest}
operating system images to be run simultaneously. Virtualizing the
machine in this manner provides considerable flexibility, for example
allowing different users to choose their preferred operating system
(e.g., Linux, NetBSD, or a custom operating system). Furthermore, Xen
provides secure partitioning between virtual machines (known as
{\em domains} in Xen terminology), and enables better resource
accounting and QoS isolation than can be achieved with a conventional
operating system.
Xen essentially takes a `whole machine' virtualization approach as
pioneered by IBM VM/370. However, unlike VM/370 or more recent
efforts such as VMWare and Virtual PC, Xen does not attempt to
completely virtualize the underlying hardware. Instead parts of the
hosted guest operating systems are modified to work with the VMM; the
operating system is effectively ported to a new target architecture,
typically requiring changes in just the machine-dependent code. The
user-level API is unchanged, and so existing binaries and operating
system distributions work without modification.
In addition to exporting virtualized instances of CPU, memory, network
and block devices, Xen exposes a control interface to manage how these
resources are shared between the running domains. Access to the
control interface is restricted: it may only be used by one
specially-privileged VM, known as {\em domain 0}. This domain is a
required part of any Xen-based server and runs the application software
that manages the control-plane aspects of the platform. Running the
control software in {\it domain 0}, distinct from the hypervisor
itself, allows the Xen framework to separate the notions of
mechanism and policy within the system.
%% chapter Virtual Architecture moved to architecture.tex
\include{src/interface/architecture}
%% chapter Memory moved to memory.tex
\include{src/interface/memory}
%% chapter Devices moved to devices.tex
\include{src/interface/devices}
%% chapter Further Information moved to further_info.tex
\include{src/interface/further_info}
\appendix
%% chapter hypercalls moved to hypercalls.tex
\include{src/interface/hypercalls}
%%
%% XXX SMH: not really sure how useful below is -- if it's still
%% actually true, might be useful for someone wanting to write a
%% new scheduler... not clear how many of them there are...
%%
%% \include{src/interface/scheduling}
%% scheduling information moved to scheduling.tex
%% still commented out
%%
%% XXX SMH: we probably should have something in here on debugging
%% etc; this is a kinda developers manual and many devs seem to
%% like debugging support :^)
%% Possibly sanitize below, else wait until new xendbg stuff is in
%% (and/or kip's stuff?) and write about that instead?
%%
%% \include{src/interface/debugging}
%% debugging information moved to debugging.tex
%% still commented out
\end{document}
|
