Assuming write-back caches, private L1 data caches (L1Ds) (no L2), shared memory, and a MESI coherence policy, indicate in the cache tables what would be the values (V) of the variables X and Y and their coherency (C) state (either M, E, S or I) in the L1D's for a dual core processor with the following sequence of reads and writes. As shown in the table, the coherency (C) state in Step 0 (the initial coherency state) of both variables in both caches is I (invalid). If a value doesn't change, you may leave that entry blank. You may use either the state transition diagram or the table given below to reason about cache coherence. Step 0: Step 1: Step 2: Initially, X =3, Y = 5 in the shared memory, processor caches are empty Core 1 reads X (from the shared memory) Core 2 reads X Core 1 writes X = 2 Core 1 writes Y = 6 Step 3: Step 4: Step 5: Core 2 reads Y Please fill in the following cache and shared memory tables (no further explanation for your answers is required).

Assuming write-back caches, private L1 data caches (L1Ds) (no L2), shared memory, and a MESI coherence policy, indicate in the cache tables what would be the values (V) of the variables X and Y and their coherency (C) state (either M, E, S or I) in the L1D's for a dual core processor with the following sequence of reads and writes. As shown in the table, the coherency (C) state in Step 0 (the initial coherency state) of both variables in both caches is I (invalid). If a value doesn't change, you may leave that entry blank. You may use either the state transition diagram or the table given below to reason about cache coherence. Step 0: Step 1: Step 2: Initially, X =3, Y = 5 in the shared memory, processor caches are empty Core 1 reads X (from the shared memory) Core 2 reads X Core 1 writes X = 2 Core 1 writes Y = 6 Step 3: Step 4: Step 5: Core 2 reads Y Please fill in the following cache and shared memory tables (no further explanation for your answers is required).

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

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