Configures a limit on the maximum number of outstanding requests per connection.
Configures a limit on the maximum number of outstanding requests per connection. Default is no limit.
Configures the NackAdmissionFilter
.
Configures the NackAdmissionFilter
. The NackAdmissionFilter
is enabled
by default and configured with the default values which can be found in
com.twitter.finagle.filter.NackAdmssionFilter.
NOTE: Here is a brief summary of the configurable params.
A configuration with a threshold
of N% and a window
of duration W
roughly translates as, "start dropping some requests to the cluster when
the nack rate averages at least N% over a window of duration W."
Here are some examples of situations with param values chosen to make the filter useful:
- Owners of Service A examine their service's nack rate over several days and find that it is almost always under 10% and rarely above 1% (e.g., during traffic spikes) or 5% (e.g., during a data center outage). They do not want to preemptively drop requests unless the cluster sees an extreme overload situation so they choose a nack rate threshold of 20%. And in such a situation they want the filter to act relatively quickly, so they choose a window of 30 seconds.
- Owners of Service B observe that excess load typically causes peak nack rates of around 25% for up to 60 seconds. They want to be aggressive about avoiding cluster overload and don’t mind dropping some innocent requests during mild load so they choose a window of 10 seconds and a threshold of 0.15 (= 15%).
Duration over which to average the ratio of nackd/non-nacked responses.
The upper limit of the fraction of responses which are
nacks before the NackAdmissionFilter
begins to drop requests.
Disables the NackAdmissionFilter
if backing off during overload situations
is not desirable behavior.
Disables the NackAdmissionFilter
if backing off during overload situations
is not desirable behavior. The NackAdmissionFilter
is enabled by default.
A collection of methods for configuring the admission control modules of Finagle clients.
a Stack.Parameterized client to configure