CSCI 3753: Operating Systems
Final Exam Practice代写 Answer all questions in the space provided1.(20 pt) Mark each term with the letter of the best definition
Final Exam Practice Final Exam Practice代写
Answer all questions in the space provided
1.(20 pt) Mark each term with the letter of the best definition
A.occurs when the operating system cannot find the data in virtualmemory
B.maintaining blocks that are not allocated to some file ordirectory
C.a range of addresses from the perspective of theOS Final Exam Practice代写
D.bit indicating the block needs to be written before beingreplaced
E.a bit to ensure that the total numberof set bits in a block is even or odd
F.allocate the same number foreach process
G.process of identifying that an intrusion has been attempted, is occurring, orhas occurred
H.a fixed size block in physicalmemory space Final Exam Practice代写
I.the ability to accommodate a single or multiple failure and still remain available
J.a reference to another file ordirectory
K.a location in the hierarchy ofdirectories at which to access another file system
L.paging for virtual memorymanagement to decide which memory pages to page out
M.a range of addresses fromthe perspective of a process
N.bit(s) used in reconstruction ofthe original data
O.a fixed size block in logicalmemory spaceFinal Exam Practice代写
P.having the same data stored onseparate storage device hardware
Q.bit indicating that the informationis currently in memory
R.managing on-disk data structuresfor files or directories
S.allocate according to the size ofprocess
T.monitoring and scanning to find unauthorized and possiblymalicious software
|logical address space||dirty bit||frame||proportional frame allocation||page replacement|
|free space management|
2.[20 Points] Multiple Choice: Select the best answer for eachquestionFinal Exam Practice代写
A.What is the advantage of storing blocks of a file near each other on thedisk?
- maximize blockusage
- parallelize datatransfer
- minimize seektime
B.If each index block holds 64 (2^6) entries, how many blocks can double indexing accessfor each file?
- 64 (2^6)
- 4096 (2^12)Final Exam Practice代写
C.Mounting a filesystem:
- can be used to bypass accessrules
- can occur anywhere in the directorytree
- must occur at the root of the directorytree
- must occur at a leaf in the directorytree
D.Log based transaction methods referto:
- checkpoints and checksums before diskoperations
- creation of log for uncommitted modifications
- disk operations that are performedsynchronously
- writing log entries for diskerrors
E.Changing the block size from 4K to 8Kwill:Final Exam Practice代写
- decrease the externalfragmentation
- decrease the internalfragmentation
- increase the externalfragmentation
- increase the internalfragmentation
F.An attempt to make a computer resource unavailable to its intended uses iscalled:
G.Which of the following makes sure that data is not changed when it is not suppose tobe?
H.What is the process of identifying anindividual?Final Exam Practice代写
I.What is the process that prevents someone from denying that they accessed aresource?
3.[20 Points] Multiple Choice: Select ALL that are true for eachquestion
A.Which object types does the VFSdefine?
B.Advantages of distributed systems include:Final Exam Practice代写
C.For paging, every address generated by the CPU is divided into:
D.Which of the following are replacement algorithms forpaging?
4.[10 Points] Given five named free memory blocks (inorder):Final Exam Practice代写
F1: 100 K, F2: 420 K, F3: 200 K, F4: 295 K, F5: 500 K
And the following space requests (in order of request):
202 K, 417 K, 118 K, 426 K, 90 K
Mark the free memory block location where the requested block will be placed using the given policy. If the request cannot be satisfied, draw a line through all blocks for that request.
Example with requests of 200K, 300K, 600K
Blocks: 250K, 400K, 500K
|202K||Final Exam Practice代写|
|118K||Final Exam Practice代写|
5.[10 Points] Given that the page table has 3 frames that are initially empty and the following page referencesequence:
2, 3, 4, 8, 2, 4, 8, 2, 6, 1, 7, 5
What does the page table look like after each page reference and what is the total number of page faults when using each of the page replacement algorithms below.
|OPT||Step 1||Step 2||Step 3||Step 4||Step 5||Step 6||Step 7||Step 8||Step 9||Step 10||Step 11||Step 12||#
|1||Final Exam Practice代写|
|FIFO||Step 1||Step 2||Step 3||Step 4||Step 5||Step 6||Step 7||Step 8||Step 9||Step 10||Step 11||Step 12||#
|2||Final Exam Practice代写|
|Least Recently Used||Step 1||Step 2||Step 3||Step 4||Step 5||Step 6||Step 7||Step 8||Step 9||Step 10||Step 11||Step 12||#
|2||Final Exam Practice代写|
1 6. [10 Points] Given that there are 400 cylinders (0-399)
and the R/W head is on cylinder 201 moving towards lower numbered cylinders, calculate the total distance (# of cylinders) travelled by the R/W head using each of the given disk scheduling methods. The following requests have been received in the following order:
232, 112, 199, 322, 0, 42, 322, 86
what does the sequence of tracks look like when using each of the algorithms below. Note: you may not need to use all the columns.
|total distance travelled
|Final Exam Practice代写|
|total distance travelled
7.[50 Points] Short answerFinal Exam Practice代写
A.What are the problems illustrated in the image below?
*NOTE: Contiguous blue boxes represent an entire process.
What is/are solutions to the problems identified above?
B.What are the advantages/disadvantages for the following disk scheduling algorithms: FCFS, SSTF, SCAN, C-SCAN, LOOK, C-LOOK?
C.How is a child process’s address space initialized after a fork() command is executed in a page sharingscheme?Final Exam Practice代写
D.You are asked to allocate a file according to the multi-level indexed allocation (UNIX inode – triply indirect). Assume that the memory block pointers to support a file containing 200K bytes of data. There are 1 KB per disk block, an index block holds 64 entries, and there are 12 direct pointers in the inode. Fill in the details of how many disk blocks are allocated for this file (NOT including the inodeitself).
- # blocks in direct blocks=
- # blocks in single indirect=
- # blocks in double indirect=
- # blocks in triple indirect=
- # metadata blocks=
E.What is the type of Redundant Arrays of Inexpensive Disks (RAID) illustrated in the below figure.
RAID 0 has worst over RAID 5.Final Exam Practice代写
8.[10 Points] Let’s look at the simple MMU that handles logical address to physical address translation using base and limit.
Select the correct labels corresponding to their numbered annotation.Final Exam Practice代写