Warmed Containers

Warmed containers can improve their performance by skipping the container initialization step. It may be beneficial to configure the number of warmed containers to keep, and the duration to keep them according to the characteristics of workloads.

Configuration

The configurations are only effective with the FPC scheduler. They can be configured using the limit configurations for each namespace.

case class UserLimits(invocationsPerMinute: Option[Int] = None,
                      concurrentInvocations: Option[Int] = None,
                      firesPerMinute: Option[Int] = None,
                      allowedKinds: Option[Set[String]] = None,
                      storeActivations: Option[Boolean] = None,
                      warmedContainerKeepingCount: Option[Int] = None,
                      warmedContainerKeepingTimeout: Option[String] = None)

So those can be configured in the same way that operators configure the invocationsPerMinute limit.

{
  "_id": "guest/limits",
  "invocationsPerMinute": 10,
  "warmedContainerKeepingCount": 8,
  "warmedContainerKeepingTimeout": "24 hours"
}

The namespace-specific configurations would override the default, system-wide configurations. In the above example, the system will keep 8 warmed containers for 24 hours even if there is no activation at all.