Suppose that the Sailor table has 50 tuples (or records) stored in 5 disk blocks and the Reserve table has 5,000 tuples (or records) stored in 500 disk blocks. Let S be Student and let R be Reserve. The following information is provided for access paths: • 7 buffer caches (pages) are available. • The Student table has the secondary index on sid with index level =1 • The Reserve table has the secondary index on sid with index level =2. • Each Student tuple matches with exactly 100 Reserve tuples Consider the join R AR.sid = S.sid S. Which one is the IO cost when using Block nested loop join? 1,000 505 None of the above O 5,105 O 10,500

Suppose that the Sailor table has 50 tuples (or records) stored in 5 disk blocks and the Reserve table has 5,000 tuples (or records) stored in 500 disk blocks. Let S be Student and let R be Reserve. The following information is provided for access paths: • 7 buffer caches (pages) are available. • The Student table has the secondary index on sid with index level =1 • The Reserve table has the secondary index on sid with index level =2. • Each Student tuple matches with exactly 100 Reserve tuples Consider the join R AR.sid = S.sid S. Which one is the IO cost when using Block nested loop join? 1,000 505 None of the above O 5,105 O 10,500

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

See similar textbooks

Similar questions

8. Consider one disk with 400 cylinders, numbered 0 to 399. Assume the current position of head is at cylinder 130. The request queue is given as follows: 150, 40, 350, 100, 280 For each of the disk-scheduling algorithms given below, show (by plotting in the graphs below) the current position of head based on the disk arm movement to satisfy the above requests, and count the total distance (in cylinders) of the disk arm movement. a. First Come First Served (FCFS) 0 40 100 130 150 Total distance (disk arm movement) = b. Shortest Seek Time First (SSTF) 0 40 100 130 150 Total distance (disk arm movement) = c. LOOK - in the direction of increasing track number 0 40 100 130 150 Total distance (disk arm movement) = 280 280 280 350 350 350 399 399 399 d. Based on questions a-c, specify the best algorithm for the given case above. Also explain TWO (2) reasons why the disk scheduling algorithm important in disk management.
What happens when a translation look-aside buffer (TLB) does not support address-space identifiers (ASIDs)? A. The TLB must be flushed every time a new page table is selected. B. The TLB can contain entries for several processes simultaneously. C. The TLB will have address-space protection for each process. D. The TLB will have unique identifier for each process.
Consider a memory of size 8KB (8192 bytes) that allows dynamic, variable sized partitioning among processes and uses a linked list to keep track of free spaces (hereafter referred to as the free list) in the memory at any given time. Assume that there are 6 processes and assume that their memory size requirements (in bytes) are as given below: Р1: 500, Р2: 600, Р3: 1300, Р4: 2000, Р5: 100, Р6: 200 Assume that the initial state of the free list is as shown below (BA is the base address and Sz is the size of each free space): ВА: 0; Sz: 1100 — ВА: 1200; Sz: 600 > BА: 2000; Sz: 1800> ВА: 6000%; Sz 400
Which fields inside an entry in a log file will be made available to be processed by the log processing function that has been specified? The following piece of code causes an average of how many cache misses per entry, assuming that cache blocks are 64 bytes in size and that no prefetching is performed.
An operating system follows a variable memory partitioning model. The system keeps track Question 31 of empty blocks in a linked list in the order of their address, where each node stores the size of next empty block in the memory. Say that current state of the memory is hold by the linked list shown below, which tells that there are currently four empty blocks in the memory, and the size of first block is 12 byte etc. 12 8 3 Assume that following memory block requests have been made in given order: 8 bytes, 2 bytes and 6 bytes. Draw the linked list to be changed after each block assignment by the following strategies; (a) First Fit (a) Best Fit
How many fields can the specified log processing function access in a log entry? Calculating average cache miss rates per entry using 64-byte blocks and no prefetching is done using the following code.
An operating system follows a variable memory partitioning model. The system keeps track of empty blocks in a linked list in the order of their address, where each node stores the size of next empty block in the memory. Say that current state of the memory is hold by the linked list shown below, which tells that there are currently four empty blocks in the memory, and the size of first block is 12 byte etc. Assume that following memory block requests have been made in given order: 8 bytes, 2 bytes and 6 bytes. Draw the linked list to be changed after each block assignment by the following strategies [12.5p each]; (a) First Fit (c) Best Fit
A company has a calculation strategy where the number of file systems needed indicates a disk with 1000 blocks. There are in total five files. Assume the end block, index block wherever required. Also, considering that the file control block contains the information in the order of Using contiguous, linked and indexed allocation methods compute the allocated files.
For an index on the SSN field, assume the field size VSSN=20 bytes, record pointer size PR=10, block size B=512 bytes and r=5000. Then find out the below: Index entry size RI Index blocking factor BfrI Number of index blocks b
To what extent does the specified log processing function have access to each field of a log entry? The following code estimates the average number of cache misses per entry while using 64-byte cache blocks and no prefetching.
In a log entry, which fields are available to the log processing function? Assuming 64-byte cache blocks and no prefetching, how many cache misses does the following code cause on average for each entry?
To what extent does the specified log processing function have access to each field of a log entry? The following code determines the typical number of cache misses per entry while using 64-byte cache blocks and no prefetching.