How can I monitor or get metrics from Vitess?
All Vitess components have a web UI that you can access to see the state of each component.
The first place to look is the /debug/status
page.
- This is the main landing page for a VTGate, which displays the status of a particular server. A list of tablets this VTGate process is connected to is also displayed, as this is the list of tablets that can potentially serve queries.
A second place to look is the /debug/vars
page. For example, for VTGate, this page contains the following items:
- VTGateApi - This is the main histogram variable to track for VTGates. It gives you a breakdown of all queries by command, keyspace, and type.
- HealthcheckConnections - It shows the number of tablet connections for query/healthcheck per keyspace, shard, and tablet type.
There are two other pages you can use to get monitoring information from Vitess in the VTGate web UI:
/debug/query_plans
- This URL gives you all the query plans for queries going through VTGate./debug/vschema
- This URL shows the VSchema as loaded by VTGate.
VTTablet has a similar web UI.
Vitess component metrics can also be scraped via /metrics. This will provide a Prometheus-format metric dump that is updated continuously. This is the recommended way to collect metrics from Vitess.