Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Q. Remapping of bad blocks by sector sparing or else sector slipping could influence performance. Presume that the drive in Subsequent Exercise has a total of 100 bad sectors at random locations and that every bad sector is mapped to a spare that is located on a different track but within the same cylinder. Estimation the number of I/Os per second and the effective transfer rate for a random-access workload consisting of 8-kilobyte reads with a queue length of 1 (that is the choice of scheduling algorithm isn't a factor). What is the consequence of a bad sector on performance?
Answer: Since the disk holds 22,400,000 sectors the probability of requesting one of the 100 remapped sectors is very small. An instance of a worst-case event is that we attempt to read say an 8 KB page however one sector from the middle is defective and has been remapped to the worst possible location on another track in that cylinder. In this situation the time for the retrieval could be 8 ms to seek plus two track switches and two full rotational latencies. It is probable that a modern controller would read all the requested good sectors from the original track before switching to the spare track to retrieve the remapped sector and thus would incur only one track switch and rotational latency. Therefore the time would be 8ms seek + 4.17 ms average rotational latency + 0.05 ms track switch + 8.3 ms rotational latency + 0.83 ms read time (8 KB is 16 sectors 1/10 of a track rotation). Therefore the time to service this request would be 21.8ms giving an I/O rate of 45.9 requests per second as well as an effective bandwidth of 367 KB/s. For a strictly time-constrained application this might matter but the overall impact in the weighted average of 100 remapped sectors and 22.4 million good sectors is nil.
Resolution of externally defined symbols is carried out by Resolution of externally defined symbols is carried out by Linker
What are the drawbacks of contiguous allocation of disk space? The disadvantages are a. Suffers from internal fragmentation b. Suffers from external fragmentation c. F
Sharing segments between processes without requiring the same segment number is possible in a dynamically linked segmentation system. a. Define a system that permits sta
Usually memory is allocated from a large pool of unused memory area called the heap. In C++, dynamic allocation/deallocation must be manually performed using commands like malloc,
The producer-consumermodel above has a standard human analogy of an assembly line. Humans have specialized skills, however, whereas threads running the same program do not need to
Q. What are the major differences between operating systems for mainframe computers and personal computers? Answer: In general operating systems for batch systems have simpler
Write a program (with the programming language and on the platform of your choice) to demonstrate the memory leak problem (see http://en.wikipedia.org/wiki/Memory_leak for detail
Q. Some untimely computers protected the operating system by placing it in a memory partition that couldn't be modified by either the user job or the operating system itself. Expl
What is the use of fork and exec system calls? Fork is a system call by which a latest process is created. Exec is also a system call, which is used after a fork by one of the
Q. To build a vigorous distributed system you must know what kinds of failures can occur. a. List three possible kinds of failure in a distributed system. b. State which of
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +1-415-670-9521
Phone: +1-415-670-9521
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd