Operating System Concept 讀書筆記

Perface

    This field is undergoing rapid changing, as computers are now in prevlent in virtually in application, from...

這句話中的virtually在這裡意思是almost，nearly。

    Concepts are presented(介紹，提出) using intuitive descriptions. 

management

    There are many different memory management schemes, reflecting various approaches to memory management, and effectiveness of a particular depends on the situation.

Effectiveness…作者是想說有多種不同的記憶體管理方案，它們是否有效取決于不同的應用。換句話雖說，使用哪種方案更有效取決于不同的應用。

Storage mamagement.

    The file system provides the mechanism for on-line storage of and access to both data and programs residing on the disks. mechanism for ... 應該這樣讀：...mechanism for on-line storage of data and programs...  ...mechanism for access to data and programs...。

    They provide a firm practical understanding of the algorithms used-the properties, advantages, and disadvantages. 這句話怎麼了解？firm understanding of ...紮實深刻的了解，used應該修飾algorithms，已經被使用的，不過used後面幾個詞是說如何understanding，實際作者是想說這些章節分析了這些應用于實際中的算法，分析了它們的特點，優勢，劣勢，這些分析能夠給與讀者深刻的了解。

    In many ways(從多方面，從多個角度), I/O devices are also...,performance issues (性能問題)are examined. Matters related to secondary and tertiary storage (???) are ...。...examined,這個詞在這裡有考慮，分析，研究的意思，在這裡作者可能是想說，因為I/O device是性能的瓶頸，是以在使用I/O devices的時候，要在性能問題上多考慮，多分析。secondary and tertiary storage,二級/三級存儲指計算機緩存技術。

Protection and scurity

...Security protects the information ..., ... and accidental introduction of inconsistency.and後面這句話的意思是說在介紹安全性方面内容時，偶爾(少量，不是主要，次要)也涉及因為對OS資訊/資源通路不一緻所引起的安全性問題。

Special-purpose systes. 

... general-purpose systems that are the foucs of the reminder of the text. 這句話中的remainder是一個令人費解的詞，它本身有剩餘的，留下的等這類意思，如果這樣，are the foucs of 剩下的文本，既然是剩下的文本，那麼其它文本呢？我想這裡的意思其實是在說一般計算機系統焦點主要集中在留在計算機系統中文本資料的處理，所謂“留在”肯定說明了有一部分被删除了，不過既然如此那麼為何不用storage in OS這類單詞呢？為何要用remainder這個單詞。

Case studies

    Both linux and FreeBSD are readily avaliable (很容易使用在....) for ... so many students have access to (可以獲得/可以使用) these systems....從字面意思來看，是以，很多學生可以得到這些systems，不過結合前文，這些system的核心算法簡單，在computer-science中很容易使用，我想這裡的“使用”意思是容易學習的意思，是以這句話中的have access to...的意思應該是...可以使用這些systems進行學習，實際上，這句話另外的含義是說隻有少數學生(比較聰明的)可以使用比較複雜的systems進行學習，一般的學生(智商一般)在學習OS時使用簡單的OS比較适用。

The Seventh Edition

    As we wrote....We have rewritten the material ...by bringing older material up to date and removing material that was no longer of interest and relevance. up to date,後置定語，最新的，最流行的等意思; ...was no longer of interest and relevance. 主體實際上是be of + n結構，相當于be+adj.可以了解為：...was no longer interesting and relevant.

Chapter 5, CPU Scheduling，...including processor affinity (親合力？什麼意思？怎樣了解) including Pthreads(???) and updated coverage of table driven scheduling (???) ...。

Chapter 6, Process Synchronization, ... We have moved the coverage of two process solutions...這句話中的coverage of two-process意思是two-process solutions範圍的大小，作者想說two-process solutions相關的全部(絕大部分)都被删掉了。

下文coverage of 多次被用到，都可以翻譯成全部的，這部分，這些等這種表示範圍程度的詞意思

Chapter9，Virtual Memory, ...A new section on...within the kernel discusses the buddy algorithm (???) and the slab allocator (???).

Teaching Supplements and Web Page

    The web page for the book contains such material as a set of slides to ...Included problems and exercise with solutions(problems and exercise的答案) not found...a set of slides 可以翻譯稱完美教程，slides有幻燈片的意思，直譯就是一組幻燈片，實際就是一組教程。

Overview

    An operationg system is a software that ....The hardware must provide appropriate mechanisms to ensure the correct operation of the computer system and to prevent user programs interfacing with the proper operationg of the system.這段話中的hardware，似乎應該是software,指代OS，從後面來看...to ensure... and to prevent...這明顯是OS的作用也就是一個software，可這裡用hardware，明顯是一個錯誤，硬體怎麼確定計算機系統的正确性？又怎麼保證使用者程式不互相幹擾？

本文轉自jetyi51CTO部落格，原文連結： http://blog.51cto.com/jetyi/304595，如需轉載請自行聯系原作者