Loader 4 種
(A)Bootstrap Loader (啟動載入器)1.在電腦開機時,用來載入第一個執行程式(通常是
作業系統)的絕對載入程式 2.不必執行連結與重定位3.單回合處理4.啟動載入程式有固定
的程式起始位址(通常為 0) 5.作業系統的起始位址亦為固定啟動6.載入程式本身應該很
小
(B)linking loader(連結載入程式)1.對一群需要連結的控制段(可重定位程式),進行連
結及載入,並執行所載入完整的程式2.由於外部參考的問題,需兩回合來完成: Pass
1: 指定位址給所有的外部變數 Pass 2: 執行實際的載入、重定位及連結
(C)linkage editor(連結編輯程式)功能和Linking Loader一樣。但是在Load之前就先做
了Link的動作。
(D)dynamic linking(動態連結程式)程式直到執行時直到執行時,才做才做Link的動作
。
Parse Tree <read> := READ ( <id-list> )
<id-list> := id VARIANCE := SUMSQ DIV 100 - MEAN * MEAN
Array 分為兩種主要格式:row major 以列為主[01.02.03.04.05.06][11.12.13...]
column major 以行為主[01.11.21.31][02.12.22.32]
算法 ex:現有一個 row major 的,
[01.02.03.04.05.06][11.12.13.14.15.16]....[31.32.33.34.35.36]
目的碼產生[A]: A:ARRAY[1..10]OF INTEGER →... →... →... → A[I] :=5
(1)- I #1 i1 (I - 1 丟到 i1)原因:
(2)* i1 #3 i2 (i1 * 3 丟到 i2)原因:1Word = 3Byte
(3):= #5 A[i2]
目的碼產生[B]: B:ARRAY[0...3,1...6]OF INTEGER →... →... →... →
A[I,J] :=5
(1)* I #6 i1 (2)- J #1 i2 (3)+ i1 i2 i3 (4)* i3 #3
i4 (5):= #5 B[i4]
FCFS、 LRU Suppose demand-paging is used in our system which allows three
pages in the memory at a time. The program to be considered consists of pages
unmbered 0 through 5. Page 4 is automatically loaded when we start running
the program. Other pages are loaded as they are referenced by the page fault
mechanism. Suppose the sequence of page references is in the following order:
4 3 5 5 5 1 1 3 5 5 4 3 5 1 3=>
(a)Show the content of the memory after each memory reference using FCFS
scheme.
(b)how many page faults are generated during the program execution?
註:FCFS(先到先服務) LRU(最近用過的優先) 答:(A)
4,*34,*534,534,534,*153,153,153,153,153,*415,*341,*534,*153,153 (B):7 Page
faults
--
▉╯╰ ▅▃▂ ▂ ▏ http://www.wretch.cc/blog/lightpink1 ╱
█ ╮╭ ▆▅ ▂▅▆ ▎ ╱ █ ╱ ╱ █ ╱
▉ ◢▋ ▄▄ ▉ ◢▋ ╱ ████████████
▉ ▆█◤ ▊ ▎ ▉ ▆█◤ ╱ ╱
█ █ ▋ ▍ ▎ █ ████████████
▉ █ ▅▅ ▏ █ █ █
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 140.137.20.1
※ 編輯: u9555kimo 來自: 140.137.20.1 (06/04 17:02)