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D.9 Delay Accuracy

1
This clause specifies performance requirements for the delay_statement. The rules apply both to delay_relative_statement and to delay_until_statement. Similarly, they apply equally to a simple delay_statement and to one which appears in a delay_alternative.

Dynamic Semantics

2
The effect of the delay_statement for Real_Time.Time is defined in terms of Real_Time.Clock: 
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5
A simple delay_statement with a negative or zero value for the expiration time does not cause the calling task to be blocked; it is nevertheless a potentially blocking operation (see 9.5.1).
6/2
When a delay_statement appears in a delay_alternative of a timed_entry_call the selection of the entry call is attempted, regardless of the specified expiration time. When a delay_statement appears in a select_alternative, and a call is queued on one of the open entries, the selection of that entry call proceeds, regardless of the value of the delay expression.

Documentation Requirements

7
The implementation shall document the minimum value of the delay expression of a delay_relative_statement that causes the task to actually be blocked. 
8
The implementation shall document the minimum difference between the value of the delay expression of a delay_until_statement and the value of Real_Time.Clock, that causes the task to actually be blocked. 

Metrics

9
The implementation shall document the following metrics: 
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NOTES
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This paragraph was deleted.

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