January 2021

Consider a 4-drive, 200GB-per-drive RAID array.What is the available data torage capacity for each of the RAID levels, 0, 1, 3, 4, 5, and 6? 12.1 What is the difference between a field and a record? 2. What is the difference between a file and a database? 3. What is a file management system? 4. […]

1.Why is the average search time to find a record in a file less for an indexed sequential file than for a sequential file? 2. What are typical operations that may be performed on a directory? 3. What is the relationship between a pathname and a working directory? 4 What are typical access rights that

1.List and briefly define three blocking methods. List and briefly define three file allocation methods. 12.1 Define: B ! block size R ! record size P ! size of block pointer F ! blocking factor; expected number of records within a block Give a formula for F for the three blocking methods depicted in Figure

1.Directories can be implemented either as “special files” that can only be accessed in limited ways, or as ordinary data files.What are the advantages and disadvantages of each approach? 2. Some operating systems have a tree-structured file system but limit the depth of the tree to some small number of levels.What effect does this limit

1.Consider a hierarchical file system in which free disk space is kept in a free space list. a. Suppose the pointer to free space is lost. Can the system reconstruct the free space list? b. Suggest a scheme to ensure that the pointer is never lost as a result of a single memory failure. 2.

1.Implement the same electronic chatroom application that you did for exercise 2. above, but this time using Java’s non-blocking I/O on the server. You may very well be able to make use of your original client program, but have the client close its socket only after it has received (and displayed) its own ‘Bye’ message

(i) Copy ShoppingCart.html from section 8.8 into your Web app’s root folder. (ii) Create your own Selection servlet, placing it in the classes folder. This servlet should generate a Web page that simply displays the name of the product selected by the user. (iii) Add the appropriate tags to your deployment descriptor and compile the servlet. (iv) Start up Tomcat (stopping

(i) Remove (or rename) the Selection servlet from the last task and then copySelection.java, Weight.java and Checkout.java from section 8.8 into the classes folder. (ii) Add the appropriate tags to your deployment descriptor and compile the three servlets. (iii) Start up Tomcat (stopping it first, if it is already running) and then access ShoppingCart.html via

1.Extend the above application to cater for selection of bananas, as well as apples and pears. 2. Further extend the above application to allow the user to enter his/her name the first time only that he/she accesses the home page during a given session. Achieve this by redirecting the user on this first occasion to a simple

(i) Copy CookieAdder.html into your Web app’s root folder. Then copy CookieAdder.java, GetPreferences.java and ShowSum.java into the classes folder (ii) Add the appropriate tags to your deployment descriptor and compile the three servlets. (iii) Start up Tomcat (stopping it first, if it is already running) and then access the above Web page via your browser. Experiment with differing input to the Web page. Notice