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talisunep Posts: 140	Posted 14:27 Mar 18, 2014 \| hi professor i was wondering if the buffer size used here in Q6 should be 50 and not 40 since the question specifies 50? 6a In pass 0, we read in the entire file of 10,000 pages, remove unwanted attributes and writes out 10,0003/5 = 6,000 pages. Since replacement sorting is used, (6000/(240)) = 75 runs are generated. On average, each run contains 80 pages. The I/O cost is 16,000 pages. 6b additional passes: log3975 = 2 the cost is 2 x 2 x 6,000 = 24,000 The number of additional passes: log(50-1)75 = 2 the cost is 2 x 2 x 6,000 = 24,000 The number of additional passes: log4975 = 2 the cost is 2 x 2 x 6,000 = 24,000 Last edited by talisunep at 16:20 Mar 18, 2014.

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talisunep

Posts: 140

Posted 14:27 Mar 18, 2014 |

hi professor i was wondering if the buffer size used here in Q6 should be 50 and not 40 since the question specifies 50?

In pass 0, we read in the entire file of 10,000 pages, remove unwanted attributes and writes out 10,000*3/5 = 6,000 pages.

Since replacement sorting is used, (6000/(2*40)) = 75 runs are generated. On average, each run contains 80 pages.
The I/O cost is 16,000 pages.

additional passes: log3975 = 2 the cost is 2 x 2 x 6,000 = 24,000

The number of additional passes: log(50-1)75 = 2 the cost is 2 x 2 x 6,000 = 24,000
The number of additional passes: log4975 = 2 the cost is 2 x 2 x 6,000 = 24,000

Last edited by talisunep at 16:20 Mar 18, 2014.