Ramp-up is an optional procedure that gradually increases the rate that a rate limiter allows — from a small value at the beginning of the ramp, typically when a node starts, up to the configured maximum.
This allows time for events such as
Just-In-Time compilation and cache-loading, before the maximum work rate applies to the node.
The ramp-up configuration of the
SystemInput rate limiter is expressed in terms of a raw number of SLEE events.
That is, the
rateIncrement specify an exact number of events.
For example, if the
startRate is 50 then ramp-up begins with an allowance of 50 events per time unit.
rateIncrement is added to the allowed rate every time Rhino processes
eventsPerIncrement events with no rejected events.
Rhino counts all events processed, regardless of whether or not they go through the
The ramp-up configuration of all other rate limiters is expressed in terms of a percentage of the maximum rate of the limiter.
For example, if
maxRate = 500 and
startRate = 25.0 then ramp-up begins with an allowance of 500 x 25.0% = 125 units of work per time unit.
Following on with this example, if
rateIncrement = 10.0 then the allowed rate increases by 500 x 10.0% = 50 units of work per time unit every time that
eventsPerIncrement units of work are used in the limiter.
Nothing special happens when the node starts — the maximum rate the SystemInput limiter allows is simply
Below is a summary of what happens when ramp-up is enabled or disabled for any other rate limiter.
Nothing special happens when the node starts — the maximum rate the rate limiter allows is simply
Ramp-up has no effect if the rate limiter’s
Ramp-up restarts from
|You configure ramp-up globally, but each node ramps up independently. So if a node restarts, it ramps up again — without affecting other already running nodes.|