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| n |
Has been
implemented on some Unix OS
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| n |
Processes are
divided into groups
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| n |
Group k has a
fraction Wk of the CPU
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| n |
The priority
Pj[i] of process j (belonging to group
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k) at time
interval i is given by:
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Pj[i] = Bj +
(1/2) CPUj[i-1] + GCPUk[i-1]/(4Wk)
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A high value
means a low priority
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Process with
highest priority is executed next
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Bj = base
priority of process j
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CPUj[i] =
Exponentially weighted average of
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processor usage
by process j in time interval i
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F |
GCPUk[i] =
Exponentially weighted average
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processor usage
by group k in time interval i
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