Performance of running Azure Functions on AKS Virtual Nodes

I have followed the instructions [here](https://docs.microsoft.com/en-us/azure/azure-functions/functions-kubernetes-keda) to set up an Azure Functions instance in a Kubernetes cluster running on a Virtual Node. Everything is working well except for the performance of virtual node creation. In all cases, it is taking the container 60-70 seconds to enter the running state.

My function has an HTTP trigger. When I use Postman to make a request, the container quickly enters the "Creating" state. After a few seconds, it transitions to the "Waiting" state, where it remains for 50-60 seconds. Finally, the container enters the "Running" state.

Is there anything that I can do to improve the performance of this operation? My containers are stored in a premium ACR instance in the same region as my AKS cluster (westus2).

Environment:
Client Version: version.Info{Major:"1", Minor:"12", GitVersion:"v1.12.8", GitCommit:"a89f8c11a5f4f132503edbc4918c98518fd504e3", GitTreeState:"clean", BuildDate:"2019-04-23T04:52:31Z", GoVersion:"go1.10.8", Compiler:"gc", Platform:"darwin/amd64"}
Server Version: version.Info{Major:"1", Minor:"14", GitVersion:"v1.14.6", GitCommit:"96fac5cd13a5dc064f7d9f4f23030a6aeface6cc", GitTreeState:"clean", BuildDate:"2019-08-19T11:05:16Z", GoVersion:"go1.12.9", Compiler:"gc", Platform:"linux/amd64"}

Size of cluster (how many worker nodes are in the cluster?)
1 Standard_F4s_v2 node + Virtual node(s)

General description of workloads in the cluster (e.g. HTTP microservices, Java app, Ruby on Rails, machine learning, etc.)

Azure Functions, running SDK version 1.0.29.