A program P reads and processes 1000 consecutive records from a sequential file F stored on device D without using any file system facilities. Given the following:
(i) Size of each record = 3200 bytes.
(ii) Access time of D = 10 m secs.
(iii) Data transfer rate of D = 800 x 103 bytes/sec
(iv) CPU time to process each record = 3 m secs.
What is the elapsed time of P if F contains unblocked records and P uses one buffer(i.e. it always reads ahead into the buffer)?
A. | 12 sec |
B. | 14 sec |
C. | 17 sec |
D. | 21 sec |
Option: B Explanation :
In case P uses one 'Read ahead' buffer the processing and transferring of records can be overlapped. Click on Discuss to view users comments. |
A program P reads and processes 1000 consecutive records from a sequential file F stored on device D without using any file system facilities. Given the following:
(i) Size of each record = 3200 bytes.
(ii) Access time of D = 10 m secs.
(iii) Data transfer rate of D = 800 x 103 bytes/sec
(iv) CPU time to process each record = 3 m secs.
What is the elapsed time of P if records of F are organized using-a blocking factor of 2 (i.e. each block on D contains two records of F) and P uses one buffer?
A. | 12 sec |
B. | 14 sec |
C. | 17 sec |
D. | 21 sec |
Option: A Explanation :
In this case 500 accesses are sufficient to transfer 1000 records. Click on Discuss to view users comments. |
Access time is the highest in the case of
A. | floppy disk |
B. | cache |
C. | swapping devices |
D. | magnetic disks |
Option: D Explanation : Click on Discuss to view users comments. |
A file organization component of a VSAM file is
A. | relative record data set. |
B. | keyed sequential data set. |
C. | entry sequential data set. |
D. | all of these |
Option: D Explanation :
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