Definition:
- We want to find out and be able to monitor the percentage of the API calls that are retrieved directly from the disk cache i.e. the hit ratio. This will then reveal the percentage of them that are retrieved from the HDD.
Purpose:
- Set a baseline of the current state
- Detect irregularities in the cache and in the use we do of it e.g. are we using the cache cleverly? should we change our caching strategy? has a newly released fetaure had an impact in this metric?
- In the case that the change of trend can easily lead back to a new release the looking for the root cause will be made easier e.g. the scope will be reduced
- Plus it will give our Product team some more data of the usage of the API that may be relevant for their short, mid and long term strategy and planning.
Notes:
- this metric may already be in hadoop
AC:
- retrieve metric
- the metric is to be seen on the dashboard