The public_dashboards_thanos_query SLI of the monitoring service (`main` stage) has an apdex violating SLO

Start time: 20 January 2021, 3:41PM (UTC)
Severity: critical
full_query: ((gitlab_component_apdex:ratio_1h{component="public_dashboards_thanos_query",monitor="global",type="monitoring"} < (1 - 14.4 * 0.001)) and (gitlab_component_apdex:ratio_5m{component="public_dashboards_thanos_query",monitor="global",type="monitoring"} < (1 - 14.4 * 0.001)) or (gitlab_component_apdex:ratio_6h{component="public_dashboards_thanos_query",monitor="global",type="monitoring"} < (1 - 6 * 0.001)) and (gitlab_component_apdex:ratio_30m{component="public_dashboards_thanos_query",monitor="global",type="monitoring"} < (1 - 6 * 0.001))) and on(env, environment, tier, type, stage, component) (sum by(env, environment, tier, type, stage, component) (gitlab_component_ops:rate_1h{component="public_dashboards_thanos_query",monitor="global",type="monitoring"}) >= 1)
Monitoring tool: Prometheus
Description: Thanos query gathers the data needed to evaluate Prometheus queries from multiple underlying prometheus and thanos instances. This SLI monitors the Thanos query HTTP interface for GitLab's public Thanos instance, which is used by the public Grafana instance. 5xx responses are considered failures.

Currently the apdex value is 95.5%.
GitLab alert: https://gitlab.com/gitlab-com/gl-infra/production/-/alert_management/63/details

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