In a main memory-disk virtual storage system, the page size is 1KByte and the OPTIMAL algorithm is used for page replacements. A given program has been allocated three page frames in the main memory and it makes the following 16 memory references when it starts executing (the addresses are given in decimal): 500, 2000, 2500, 800, 4000, 1000, 5500, 1500, 2800, 400, 5000, 700, 2100, 3500, 900, 2400 Fill in the contents of the three page frames after each memory reference in a table and calculate the hit ratio. Hint: denote by 'a' the page consisting of locations 0 through 1023 in memory. Similarly, b: 1024-2047, c: 2048-3071, d: 3072-4095, e: 4096-5119 and f: 5120-6143. Round to three decimal places.

In a main memory-disk virtual storage system, the page size is 1KByte and the OPTIMAL algorithm is used for page replacements. A given program has been allocated three page frames in the main memory and it makes the following 16 memory references when it starts executing (the addresses are given in decimal): 500, 2000, 2500, 800, 4000, 1000, 5500, 1500, 2800, 400, 5000, 700, 2100, 3500, 900, 2400 Fill in the contents of the three page frames after each memory reference in a table and calculate the hit ratio. Hint: denote by 'a' the page consisting of locations 0 through 1023 in memory. Similarly, b: 1024-2047, c: 2048-3071, d: 3072-4095, e: 4096-5119 and f: 5120-6143. Round to three decimal places.

Systems Architecture

7th Edition

ISBN:9781305080195

Author:Stephen D. Burd

Publisher:Stephen D. Burd

Chapter11: Operating Systems

Section: Chapter Questions

Problem 21VE

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In a main memory-disk virtual storage system, the page size is 1KByte and the FIFO algorithm is used for page replacements. A given program has been allocated three page frames in the main memory and it makes the following 16 memory references when it starts executing (the addresses are given in decimal):500, 2000, 2500, 800, 4000, 1000, 5500, 1500, 2800, 400, 5000, 700, 2100, 3500, 900, 2400 Fill in the contents of the three page frames after each memory reference in a table and calculate the hit ratio. Hint: denote by 'a' the page consisting of locations 0 through 1023 in memory. Similarly, b: 1024-2047, c: 2048-3071, d: 3072-4095, e: 4096-5119 and f: 5120-6143. Round to three decimal places.
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