Exclude OPTIONS messages from metrics

[alicel]

Aside from being used to negotiate supported features in some , OPTIONS messages are sometimes used as a heartbeat / keepalive mechanism by some drivers.

At the moment the proxy handles OPTIONS messages as generic messages, routing them to both clusters and tracking them into "forward to both" metrics, which typically represent writes. Seeing OPTIONS counted and displayed in metrics labelled as writes can be confusing, especially when running small manual tests where these "spurious" requests are not drowned out by legitimate write activity.

We should exclude OPTIONS from the messages that are tracked in the metrics, similarly to what we do for other messages such as STARTUP and REGISTER.

┆Issue is synchronized with this Jira Task by Unito
┆Components: Proxy
┆Issue Number: ZDM-541

[sync-by-unito]

➤ Wei Deng commented:

For now, we can add a new troubleshooting tip, before the new metrics are implemented.