Concurrency in the pool manager allows specializing pods concurrently based on a specified limit.
Co-authored-by: Vishal <vishal-biyani@users.noreply.github.com>
Previously, once the executor is deleted for reasons (like upgrade or cluster scale-in),
the new executor deletes all existing resources created by the old executor and creates
new one. This mechanism becomes a problem when there are requests connecting to the
existing pods. Also in the worst case, the cluster may not have enough resources to create
new pods and cause service downtime.
This PR let each executor type adopts existing resources before starting the executor
API services, and so the alive connections won't experience failure. However, the requests
send to the function that doesn't have alive function pods will still fail due to the
executor is in bootstrapping.
The pool manager keeps terminating function pod periodically even there are
traffic to the function. The root cause is that executor, poolmgr, newdeploy
manage their own functionServiceCache separately. And when router taps a
function, executor updates the access time of the function service entry in its
own cache without notifying executor types to do the update as well. Hence,
the access time of function service entry in poolmanager cache never gets updated.
Due to the access time never gets updated, the idle pod reaper in poolmanager
then thinks the function pod is in idle state and recycle it.
This PR removes the cache in executor itself, and when router tries to tap a function,
executor will call executor type to tap the function and update access time.
When a function with executor type newdeploy got created, Newdeploy
is expected to create deployment/HPA/service for it and insert serviceEntry
to the cache for later use. Once clients call the function, newdeploy returns
the serviceEntry to the router.
However, the log shows that the newdeploy was unable to find the entry and
prints "Resource not found - key 'xxx' not found". The root cause is that the
informer controller instead of processing items in parallel, it dispatches XXFunc
to process items one by one. So if there is any problem during the creation of the
kubernetes resource, it takes a longer time to process the next item and hence
the serviceEntry was not inserted before clients call the function.
This PR lets the newdeploy to process items in extra goroutines instead of blocking
the process loop. It's a workaround to solve the problem above, we should consider
using workqueue to solve it in the future.
If a user deploys fission in the namespace which is different from the one in the single YAML file generated by helm, fission components won't be able to talk to each other due to the wrong namespace appends after the service address.
This PR adds --namespace when generating the YAML file to prevent the mismatch problem.
* Config and secret change to invoke function update
* Added recycle function for pool manager as well - where it recycles the specialized pods
* Switched to rolling update of pods and env variable based change instead of deleting pods in new deploy executor
This PR removes not so useful logs and changes most of Info level
log to Debug/Error level in hot path while preserving some of them
that is helpful for troubleshooting.
