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| Problem: Inconsistent |
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| Data Views |
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| ä | 3
variables: A, B, C which are shared by |
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| thread
T1 and thread T2 |
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| ä | T1
computes C = A+B |
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| ä | T2
transfers amount X from A to B |
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| ä | T2
must do: A = A-X and B = B+X (so that |
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| A+B
is unchanged) |
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| ä | But
if T1 computes A+B after T2 has done |
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| A =
A-X but before B = B+X, T1 will not |
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| obtain
the correct result for C = A + B |
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| ä | Solution:
critical sections (later) |
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