What is the MOST resource-efficient way to configure the Mule application’s CloudHub deployment to help the company cope with this performance challenge?

A retail company is using an Order API to accept new orders. The Order API uses a JMS queue to submit orders to a backend order management service. The normal load for orders is being handled using two (2) CloudHub workers, each configured with 0.2 vCore. The CPU load of each CloudHub worker normally runs well below 70%. However, several times during the year the Order API gets four times (4x) the average number of orders. This causes the CloudHub worker CPU load to exceed 90% and the order submission time to exceed 30 seconds. The cause, however, is NOT the backend order management service, which still responds fast enough to meet the response SLA for the Order API.

What is the MOST resource-efficient way to configure the Mule application’s CloudHub deployment to help the company cope with this performance challenge?
A . Permanently increase the size of each of the two (2) CloudHub workers by at least four times (4x) to one (1) vCore
B. Use a vertical CloudHub autoscaling policy that triggers on CPU utilization greater than 70%
C. Permanently increase the number of CloudHub workers by four times (4x) to eight (8) CloudHub workers
D. Use a horizontal CloudHub autoscaling policy that triggers on CPU utilization greater than 70%

View Answer

Answer: D

Explanation

Correct Answer. Use a horizontal CloudHub autoscaling policy that triggers on CPU utilization greater than 70%

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The scenario in the question is very clearly stating that the usual traffic in the year is pretty well handled by the existing worker configuration with CPU running well below 70%. The problem occurs only "sometimes" occasionally when there is spike in the number of orders coming in.

So, based on above, We neither need to permanently increase the size of each worker nor need to permanently increase the number of workers. This is unnecessary as other than those "occasional" times the resources are idle and wasted.

We have two options left now. Either to use horizontal Cloudhub autoscaling policy to automatically increase the number of workers or to use vertical Cloudhub autoscaling policy to automatically increase the vCore size of each worker. Here, we need to take two things into consideration: