Interfaces
Page 312 7750 SR Interface Configuration Guide
Virtual Scheduler Commands
rate-calc-min-int
Syntax rate-calc-min-int [fast-queue percent-of-default] [slow-queue percent-of-default]
no rate-calc-min-int
Context config>card>virt-sched-adj
Description This command overrides the default minimum time that must elapse before a queue’s offered rate may be
recalculated. A minimum time between offered rate calculations is enforced to both prevent inaccurate esti-
mation of the offered rate and excessive input to the virtual scheduler process.
In order to smooth out rapidly fluctuating offered rates, the system averages the measured offered rate with a
window of previously measured offered rates. The window size is based on 4x the minimum rate calculation
interval. Any previous measured offered rates within the window are used in the averaging function.
The system separates queues into fast and slow categories and maintains a separate minimum recalc interval
for each type. The default minimum recalculation times for each type are as follows:
Slow Queue
Minimum Rate Calculation Interval: 0.1875 Seconds
Averaging Window Size: 0.75 Seconds
Fast Queue
Minimum Rate Calculation Interval: 0.0625 Seconds
Averaging Window Size: 0.25 Seconds
The actual minimum rate calculation interval may be increased or decreased by using the fast-queue and/or
slow-queue keywords followed by a percent value which is applied to the default interval. The default slow-
queue threshold rate is 1Mbps. Once a queue is categorized as slow, its rate must rise to 1.5Mbps before
being categorized as a fast queue. The categorization threshold may be modified by using the slow-queue-
thresh command.
The no rate-calc-min-interval command is used to restore the default fast queue and slow queue minimum
rate calculation interval.
Parameters fast-queue percent-of-default: — The fast-queue percent-of-default parameter is optional and is used to
modify the default minimum rate calculation time for “fast” queues. Defining 100.00 percent is equiva-
lent to removing the override (restoring the default) on the fast queue minimum rate calculation time.
Values 0.01% to 1000.00%
Default 100.00%
slow-queue percent-of-default: — The slow-queue percent-of-default parameter is optional and is used to
modify the default minimum rate calculation time for “slow” queues. Defining 100.00 percent is equiv-
alent to removing the override (restoring the default) on the slow queue minimum rate calculation time.
Values 0.01% to 1000.00%
To Next Page
Loading...
