What is Recording rule? Meaning, Architecture, Examples, Use Cases, and How to Measure It (2026 Guide)

Terminology

Quick Definition (30–60 words)

A recording rule is a precomputed time-series expression saved as a new metric for faster queries and reliable SLIs. Analogy: like materialized views for metrics. Formal: a server-side rule that evaluates an expression periodically and stores the result as a labeled time-series.


What is Recording rule?

A recording rule is a configuration construct in observability systems that evaluates a metric or expression on a schedule and writes the result as a new time-series. It is primarily a performance and reliability optimization: compute once centrally rather than repeatedly at query time. It is NOT a replacement for raw instrumentation or a full ETL pipeline.

Key properties and constraints

  • Runs server-side at scheduled intervals.
  • Emits new time-series with stable labels and metric names.
  • Reduces query latency, CPU use, and inconsistent calculations.
  • Requires careful label management to avoid time-series explosion.
  • Evaluation frequency impacts accuracy and cost.

Where it fits in modern cloud/SRE workflows

  • Precomputes expensive aggregations used by SLIs and dashboards.
  • Enables stable SLI definitions for SLO enforcement and alerting.
  • Integrates with CI/CD as a configuration artifact.
  • Used in multi-tenant cloud, Kubernetes, serverless, and SaaS observability platforms.

Diagram description

  • Component A: Metric ingestion from services.
  • Component B: TSDB storing raw metrics.
  • Component C: Recording rule evaluator periodically runs expressions against TSDB.
  • Component D: Evaluator writes back new labeled time-series into TSDB.
  • Component E: Dashboards and alerting query the precomputed series.
  • Data flows: services -> TSDB -> evaluator -> TSDB -> dashboards/alerts.

Recording rule in one sentence

A recording rule evaluates an expression periodically and stores the result as a new metric so queries and alerts use a consistent, efficient time-series.

Recording rule vs related terms (TABLE REQUIRED)

ID Term How it differs from Recording rule Common confusion
T1 Alerting rule Triggers alerts when conditions match Confused with precomputation
T2 Query Ad-hoc request for data Not persisted automatically
T3 Metric Raw or derived time-series Recording rule produces metrics
T4 Aggregation Operation on series Recording rule stores aggregation
T5 Materialized view DB concept similar in purpose Not identical tech implementation
T6 Derived metric Conceptual result Recording rule implements derived metrics
T7 Continuous export Copies data elsewhere Not an evaluator for expressions
T8 Histogram bucket Raw bucket data Recording rules often summarize buckets
T9 Rollup Long-term aggregation Recording rule can be used for rollups
T10 TSDB retention Storage policy Separate from recording rule function

Row Details (only if any cell says “See details below”)

  • None.

Why does Recording rule matter?

Business impact

  • Revenue: Faster and more reliable SLI calculations reduce customer-facing downtime and potential revenue loss.
  • Trust: Consistent, auditable metrics build stakeholder confidence.
  • Risk: Proper precomputation avoids missed alerts and false positives that cause incidents.

Engineering impact

  • Incident reduction: Stable SLI inputs reduce alert flapping and misdiagnosis.
  • Velocity: Engineers spend less time optimizing dashboards and more time building features.
  • Cost control: Computation centralization reduces redundant query cost across many dashboards.
  • Toil reduction: Pre-defined rules reduce repeated ad-hoc query work.

SRE framing

  • SLIs/SLOs: Recording rules give deterministic SLI inputs with consistent labels and windows.
  • Error budgets: Accurate precomputed metrics improve burn-rate fidelity.
  • On-call: Less noisy alerts and faster page resolution.
  • Toil: Automate common computations to reduce manual toil.

What breaks in production (realistic examples)

  1. SLI computed differently in multiple dashboards causing inconsistent SLO breaches.
  2. Ad-hoc heavy queries spike the observability backend CPU and cause query timeouts.
  3. Missing label normalization leads to cardinality explosion and OOM in TSDB.
  4. Alert rule uses raw computation and flaps due to scrape jitter.
  5. Retrospective analysis impossible because ad-hoc queries were not stored and data retention removed raw series.

Where is Recording rule used? (TABLE REQUIRED)

ID Layer/Area How Recording rule appears Typical telemetry Common tools
L1 Edge Rate summaries per POP request rate error rate latency Observability backends
L2 Network Flow aggregates per link bytes packets errors Network telemetry systems
L3 Service SLI series like success_rate request_count error_count latency_ms Prometheus Cortex Mimir
L4 Application Business KPIs computed from metrics transactions revenue events APM and metrics systems
L5 Data ETL job success ratios job_duration rows_processed Metrics pipelines
L6 Kubernetes Per-pod aggregated CPU memory cpu_seconds memory_bytes restarts Prometheus KSM Thanos
L7 Serverless Invocation success rates invocations errors duration Cloud monitoring managed services
L8 CI/CD Build success rate over time build_duration success_count CI metrics exporters
L9 Security Auth failure rates by user auth_attempts failures SIEM metrics
L10 Observability Dashboard-friendly precomputed metrics SLI series rollups Observability platforms

Row Details (only if needed)

  • None.

When should you use Recording rule?

When it’s necessary

  • SLIs/SLOs require consistent, auditable metrics.
  • Computation is expensive and reused widely.
  • Query latency or backend CPU is a problem.
  • You need stable metric names and labels for alerting.

When it’s optional

  • Simple, infrequent queries that are cheap to compute.
  • One-off analysis that won’t be reused.

When NOT to use / overuse it

  • For low-reuse ad-hoc queries.
  • For high-cardinality labels that explode series count.
  • For computations that require real-time millisecond-level accuracy; recording interval adds latency.

Decision checklist

  • If X and Y -> do this:
  • If computation reused by >3 dashboards and is expensive, use a recording rule.
  • If A and B -> alternative:
  • If labels cause more than 1000x cardinality growth and reuse is low, avoid recording rule; pre-aggregate client-side or drop labels.

Maturity ladder

  • Beginner: Use recording rules for top-level SLIs (request_success_rate) at low frequency.
  • Intermediate: Add controlled rollups and label normalization rules; version rule names.
  • Advanced: Automate rule deployment in CI, validate against canary data, tie rule changes to observability SLOs and infra autoscaling.

How does Recording rule work?

Components and workflow

  1. Rule config: rules are written in a domain language (e.g., PromQL, proprietary).
  2. Evaluator: scheduler executes the rule periodically.
  3. Query engine: reads raw series for inputs.
  4. Write-back: evaluator writes results as new time-series with metric name and labels.
  5. Storage: TSDB persists precomputed series with retention.
  6. Consumers: dashboards, alerts, SLO calculators read the new series.

Data flow and lifecycle

  • Ingestion: metrics from clients arrive in TSDB.
  • Evaluation: at T0, evaluator queries inputs and computes expression.
  • Emission: evaluator writes new sampled point for metric_name{labels}.
  • Retention: recorded series follow retention and compaction rules.
  • Deprecation: old rules are removed and series may be orphaned; governance needed.

Edge cases and failure modes

  • Duplicate writes if multiple evaluators run the same rule without leader election.
  • Drift due to differing evaluation intervals vs scrape intervals.
  • Label cardinality explosion from unbounded label values.
  • Miscomputed SLI due to partial data or write failures.

Typical architecture patterns for Recording rule

  1. Single-cluster evaluator storing local recordings – Use when low latency local queries are required.
  2. Centralized evaluator with multi-tenant rules – Use for consistent SLI across many tenants.
  3. Sidecar precomputation at service level – Use when raw metrics aren’t accessible centrally or cost of repeated queries is high.
  4. Rollup chain (hourly/day rollups stored separately) – Use for long-term retention and cost savings.
  5. Hybrid hybrid-cloud with federated evaluation – Use when data locality and privacy restrict centralization.

Failure modes & mitigation (TABLE REQUIRED)

ID Failure mode Symptom Likely cause Mitigation Observability signal
F1 High cardinality TSDB OOM or slow writes Unbounded label values Drop or normalize labels Metric churn rate
F2 Duplicate writes Conflicting series points Multiple evaluators writing Leader election or dedupe Write conflict logs
F3 Stale data SLI lagging real traffic Long eval interval or failures Increase frequency or retry Eval latency metric
F4 Incorrect aggregation Wrong SLI numbers Wrong expression or label misuse Unit test rules and CI Diff between raw and recorded
F5 Resource exhaustion CPU spikes during eval Too many rules or heavy queries Rate-limit rules, batching Evaluator CPU usage
F6 Retention mismatch Missing historical points Recording series retention shorter Align retention policies Missing data alerts

Row Details (only if needed)

  • None.

Key Concepts, Keywords & Terminology for Recording rule

(Glossary of 40+ terms; each line has Term — definition — why it matters — common pitfall)

Metric — A time-series of numeric measurements — Primary data for recording rules — Confusing metric vs label Time-series — Sequence of timestamped metric samples — Fundamental storage unit — Misaligned timestamps cause errors Label — Key value pair attached to series — Enables filtering and grouping — High-cardinality misuse Cardinality — Number of unique time-series — Affects TSDB cost and performance — Underestimating growth TSDB — Time-series database — Stores metrics efficiently — Not all TSDBs handle cardinality equally Scrape — Pulling metrics from endpoints — Source of input data — Irregular scrapes lead to gaps Push gateway — Component to push metrics — Useful for batch jobs — Misuse increases cardinality Aggregation — Summarize series by function — Reduces volume and computes SLI — Wrong aggregation window Rate — Per-second delta measurement — Useful for counters — Incorrect counter handling yields negative rates Counter — Monotonic metric — Used for rates — Not resetting properly causes errors Gauge — Point-in-time metric — Good for current state — Confusing with counters Histogram — Bucketed distribution metric — Allows latency quantiles — Expensive if many buckets Quantile — Value at percentile — Important for user experience metrics — Misinterpreting sample population Rollup — Long-term aggregation — Saves storage — Lossy for fine-grained analysis Retention — How long data is kept — Affects postmortem capabilities — Too short loses context Evaluation interval — How often rules run — Balances accuracy and cost — Too infrequent causes lag Materialization — Persisting computed results — Makes queries fast — Requires governance Versioning — Keeping rule versions — Important for audit and consistency — No rollbacks cause mismatch Label normalization — Transform labels to canonical form — Prevents explosion — Over-normalizing loses context Deduplication — Removing duplicate series — Prevents conflicts — Improper dedupe hides real issues Leader election — Single evaluator active — Prevents duplicates — Misconfigured election leads to no evals Partial response — Not all data returned from shards — Can cause incorrect aggregates — Alert on partial responses Staleness — Data points missing or old — Leads to wrong SLI — Tune staleness handling Alerting rule — Rule that triggers incident pages — Different from recording rule — Using it for precompute causes noise SLO — Service Level Objective — Target the SRE team cares about — Bad SLOs misprioritize work SLI — Service Level Indicator — The metric used for SLOs — Poor SLI definition misleads Error budget — Allowance for failures — Drives release cadence — Not tracking causes risky releases Burn rate — How fast budget is spent — Used for escalations — Poor measurement delays action On-call runbook — Steps for remediation — Reduces MTTR — Stale runbooks waste time Playbook — Procedural incident instructions — Facilitates consistent response — Overly generic playbooks fail Canary — Partial deployment test — Limits blast radius — No canary for rule config is risky CI/CD pipeline — Automates deployment of rules — Ensures repeatable rollout — Missing tests lead to production pain Chaos testing — Exercises failure modes — Finds real-world problems — Too destructive without guards Observability pipeline — Ingest, process, store, query — Context for recording rules — Pipeline gaps break rules Cost allocation — Mapping metrics cost to owners — Enables chargeback — Not charging cost leads to overspend Telemetry — The raw observable data — Input for rules — Poor instrumentation yields bad rules APM — Application Performance Monitoring — Complements metrics — Overreliance on one source misses system view Namespace — Metric naming scope — Avoids collisions — Confusing namespaces cause duplicate series Sampling — Reducing data volume — Lowers cost — Biased sampling misleads Backfill — Populate historical series after rule creation — Ensures continuity — Improper backfill duplicates data Governance — Policy for rules lifecycle — Prevents orphaned series — No governance causes sprawl Audit trail — Record of rule changes — Important for compliance — No audit leads to trouble Cost cap — Limits compute used by rules — Controls spend — Too tight caps cause missed evaluations


How to Measure Recording rule (Metrics, SLIs, SLOs) (TABLE REQUIRED)

ID Metric/SLI What it tells you How to measure Starting target Gotchas
M1 Recording eval success rate Reliability of rule evaluations Successful evals / scheduled evals 99.9% daily Partial response affects result
M2 SLI agreement diff Drift between raw and recorded abs(recorded – canonical)/canonical <1% typical Canonical must be defined
M3 Query latency reduction Benefit of recording rule avg query latency before/after 30% reduction target Measurement windows must match
M4 Recorder CPU usage Cost of running rules CPU seconds per minute Varies by env Spikes during rollout
M5 Created series count Cardinality impact delta series count after rule Controlled growth limit Hidden labels can explode
M6 Storage growth Disk cost due to recordings GiB per day added Keep under 10% of TSDB Retention mismatch inflates
M7 Alert accuracy False positive/negative rate FP and FN counts for alerts FP <5% FN <2% Alert rule logic matters
M8 SLO compliance Business-level performance Percent time SLI meets SLO Depends on target SLO targets vary by service
M9 Eval latency Time to compute rule Histogram of eval durations p95 < eval interval Slow queries cause spillover
M10 Backfill success Historical continuity Points backfilled / expected 100% for past N days Duplicate point prevention needed

Row Details (only if needed)

  • None.

Best tools to measure Recording rule

Tool — Prometheus / compatible (Cortex Mimir Thanos)

  • What it measures for Recording rule: evaluator success, eval latency, resulting time-series.
  • Best-fit environment: Kubernetes, self-hosted, cloud-native.
  • Setup outline:
  • Deploy rule files in config map or versioned repo.
  • Use rule groups and evaluation interval settings.
  • Expose internal metrics for evaluator.
  • Monitor recording_rule_evaluations_total and duration metrics.
  • Validate recorded series existence after deployment.
  • Strengths:
  • Open standard and portable.
  • Native to many Kubernetes setups.
  • Limitations:
  • Scale challenges for very large rule counts.
  • Requires careful label management.

Tool — Managed cloud metrics service

  • What it measures for Recording rule: managed evaluation metrics and stored series analytics.
  • Best-fit environment: Serverless and managed PaaS users.
  • Setup outline:
  • Use provider console or API to create rules.
  • Rely on provider logging for eval success.
  • Integrate with provider alerting.
  • Strengths:
  • Low ops overhead.
  • Tight integration with cloud resources.
  • Limitations:
  • Less control over evaluation frequency and retention.
  • Cost and feature variability.

Tool — Observability platform (SaaS)

  • What it measures for Recording rule: precompute usage, series growth, and dashboards impact.
  • Best-fit environment: Multi-cloud orgs, hybrid infra.
  • Setup outline:
  • Define derived metrics via UI or config.
  • Monitor platform usage and billing impact.
  • Use platform APIs to validate rules.
  • Strengths:
  • Fast setup and centralized governance.
  • Built-in dashboards for rule impact.
  • Limitations:
  • Proprietary behavior and vendor lock-in.

Tool — Custom CI checks

  • What it measures for Recording rule: rule linting, label cardinality estimation, unit test pass/fail.
  • Best-fit environment: Teams practicing infrastructure as code.
  • Setup outline:
  • Add lint rules to CI pipeline.
  • Include cardinality estimation tool.
  • Run rule compatibility tests on PRs.
  • Strengths:
  • Early failure detection.
  • Enforces governance.
  • Limitations:
  • Requires engineering effort to maintain.

Tool — Cost allocation tooling

  • What it measures for Recording rule: cost per rule or per metric series.
  • Best-fit environment: Organizations tracking observability spend.
  • Setup outline:
  • Map metric series to owner tags.
  • Track storage and query cost delta.
  • Alert on cost spikes from new rules.
  • Strengths:
  • Helps chargeback and cost control.
  • Limitations:
  • Cost attribution can be imprecise.

Recommended dashboards & alerts for Recording rule

Executive dashboard

  • Panels:
  • SLO compliance overview using recorded SLIs.
  • Monthly storage and cost impact of recording rules.
  • Top 10 rules by CPU and series growth.
  • Incident count linked to SLI breaches.
  • Why: Gives leadership quick view of business impact and observability cost.

On-call dashboard

  • Panels:
  • Current SLI values from recorded series.
  • Recording eval success and last run time.
  • Recent eval latency histogram.
  • Alert status for SLI breaches and rule failures.
  • Why: Focused operational view for incident response.

Debug dashboard

  • Panels:
  • Raw input series vs recorded series comparison.
  • Label cardinality over time.
  • Per-rule evaluation log snippets and errors.
  • Backfill and retention status.
  • Why: Allows engineers to validate logic and diagnose discrepancies.

Alerting guidance

  • Page vs ticket:
  • Page: SLI breach causing customer impact or evaluator failing across many rules.
  • Ticket: Single non-critical rule failing or storage growth anomaly.
  • Burn-rate guidance:
  • If burn rate > 2x for 1 hour, page Tier 1 on-call for SLO mitigations.
  • Escalate at 4x sustained for 15 minutes.
  • Noise reduction tactics:
  • Dedupe alerts by service and SLO.
  • Grouping by SLO and severity.
  • Suppression windows during planned maintenance.

Implementation Guide (Step-by-step)

1) Prerequisites – Centralized metric ingestion and TSDB. – Version-controlled rule repository. – CI pipeline for linting and tests. – Owner and governance for rule lifecycle.

2) Instrumentation plan – Define canonical metric names and labels. – Avoid unbounded labels and add normalization. – Ensure counters and histograms follow best practices.

3) Data collection – Ensure reliable scraping or push mechanisms. – Monitor scrape success and latency. – Tag series with ownership metadata.

4) SLO design – Choose user-centric SLIs. – Define SLO targets and error budgets. – Map SLIs to recording rules with stable names.

5) Dashboards – Replace ad-hoc queries with recorded series. – Build executive, on-call, and debug dashboards. – Validate dashboards against raw series.

6) Alerts & routing – Use recorded series in alert rules. – Route alerts by SLO ownership. – Implement escalation and burn-rate based paging.

7) Runbooks & automation – Create runbooks for rule failures, cardinality spikes, and rollbacks. – Automate rollbacks of rule changes if they cause spikes. – Automate backfill where supported.

8) Validation (load/chaos/game days) – Run load tests and simulate rule failures. – Include recording rules in chaos experiments. – Measure SLI fidelity and alert behavior.

9) Continuous improvement – Review recorded rule performance weekly. – Retire unused rules. – Track cost and impact metrics.

Pre-production checklist

  • Lint passed for new rules.
  • Cardinality estimate under threshold.
  • Unit test comparing recorded to canonical data.
  • Peer review and owner assigned.
  • Backfill plan for historical continuity.

Production readiness checklist

  • Rule deployed to canary cluster.
  • Eval success monitored for 24–72 hours.
  • Storage and CPU budget confirmed.
  • Dashboards updated to use recorded series.
  • Runbook updated.

Incident checklist specific to Recording rule

  • Confirm eval success and last run.
  • Check evaluator logs for errors.
  • Compare raw input to recorded series.
  • Rollback rule changes if recent deploy.
  • Apply mitigation such as rate limiting or label trimming.

Use Cases of Recording rule

1) SLI for user-visible success rate – Context: Web service with many dashboards. – Problem: Different dashboards compute success differently. – Why it helps: Centralized SLI metric ensures one source of truth. – What to measure: recorded_success_rate per service. – Typical tools: Prometheus, Cortex.

2) Latency p95 precompute – Context: High-cardinality latencies across endpoints. – Problem: p95 queries expensive and slow. – Why it helps: Precompute p95 per service for dashboards and alerts. – What to measure: recorded_p95_latency_ms. – Typical tools: Histogram rollups, APM integrations.

3) Long-term rollups for cost reduction – Context: Retention required but raw data expensive. – Problem: Storing high-res data long-term is costly. – Why it helps: Daily/hourly rollups reduce storage. – What to measure: daily_aggregate_request_count. – Typical tools: TSDB rollup features, Thanos.

4) Security anomaly precompute – Context: Auth failures across regions. – Problem: Detecting spikes in near real-time. – Why it helps: Precompute normalized rates per user category. – What to measure: auth_failure_rate_normalized. – Typical tools: SIEM, metrics exporters.

5) CI health metrics – Context: Multiple CI pipelines. – Problem: Frequent ad-hoc queries for build health. – Why it helps: Recorded metrics for build success rate reduce query load. – What to measure: ci_pipeline_success_rate. – Typical tools: CI exporters.

6) Serverless cold-start tracking – Context: Serverless functions across regions. – Problem: Measuring cold-start impact is noisy. – Why it helps: Precompute cold-start rate per function for SLOs. – What to measure: function_cold_start_rate. – Typical tools: Cloud monitoring, managed metrics.

7) Multi-tenant billing metrics – Context: SaaS product billing by usage. – Problem: Recompute usage for invoices causes heavy queries. – Why it helps: Precompute tenant usage series for accurate invoices. – What to measure: tenant_daily_usage_units. – Typical tools: Metering pipeline, Prometheus.

8) Network link utilization rollups – Context: Edge POPs sending link metrics. – Problem: High-frequency raw metrics overwhelm storage. – Why it helps: Rollup per link reduces data while preserving trends. – What to measure: link_hourly_bytes. – Typical tools: Telemetry collectors.

9) A/B experiment metrics – Context: Feature flags and experiments across cohorts. – Problem: Recomputations produce inconsistent results. – Why it helps: Precompute cohort metrics for consistent experiment analysis. – What to measure: cohort_conversion_rate_recorded. – Typical tools: Experiment telemetry systems.

10) Backfillable SLA reports – Context: Compliance reporting requires historical SLAs. – Problem: No precomputed historical series to audit. – Why it helps: Recording rules with backfill support ensure auditable records. – What to measure: sla_compliance_windowed. – Typical tools: TSDB with backfill APIs.


Scenario Examples (Realistic, End-to-End)

Scenario #1 — Kubernetes SLI for API success rate

Context: A microservices API running on Kubernetes with Prometheus and Mimir. Goal: Provide a single reliable success_rate SLI for paging and dashboards. Why Recording rule matters here: Reduces query CPU from multiple dashboards and ensures consistent SLO enforcement. Architecture / workflow: Kube exporters -> Prometheus remote write -> Centralized rule evaluator -> Recorded series in TSDB -> Alerting and dashboards consume recorded series. Step-by-step implementation:

  • Define canonical success counter labels.
  • Write recording rule request_success_rate = sum(rate(http_requests_total{code=~”2..”}[5m])) / sum(rate(http_requests_total[5m])).
  • Lint and run unit test comparing raw vs recorded.
  • Deploy to canary Prometheus evaluator.
  • Monitor eval success and compare p99 latency.
  • Promote to production and flip dashboards and alerts to use new metric. What to measure:

  • Eval success rate M1, recorded series count M5, query latency reduction M3. Tools to use and why:

  • Prometheus for rules, Mimir for scale, Grafana for dashboards. Common pitfalls:

  • Using user_id as label causing cardinality explosion. Validation:

  • Inject traffic with known success ratio and validate recorded metric matches. Outcome:

  • Reduced alert noise and 40% reduction in query latency.

Scenario #2 — Serverless cold-start SLO on managed PaaS

Context: Functions running on managed serverless platform with cloud metrics. Goal: Create SLO on cold-start rate for user-facing functions. Why Recording rule matters here: Cloud provider computes derived metric centrally and exposes a stable metric to SLO tooling. Architecture / workflow: Function telemetry -> provider metrics -> managed recording rules -> recorded series -> SLO engine. Step-by-step implementation:

  • Identify cold start metric emitted by runtime.
  • Create provider-side derived metric recording rule to compute sliding-window cold_start_rate.
  • Create SLO on recorded metric with 99% target.
  • Configure alerts and runbook for function owners. What to measure:

  • Cold start rate, eval success, alert false positive rate. Tools to use and why:

  • Managed cloud monitoring for ease of ops. Common pitfalls:

  • Provider evaluation interval not matching function invocation patterns. Validation:

  • Deploy a test function and simulate traffic spikes to measure cold start. Outcome:

  • Measurable reduction in cold-start incidents after tuning concurrency.

Scenario #3 — Incident response and postmortem SLI reconciliation

Context: Major outage triggered ambiguous alerts during an incident. Goal: Ensure SLI calculations used in postmortem are deterministic and auditable. Why Recording rule matters here: Recorded metrics provide immutable series for postmortem timelines. Architecture / workflow: Instrumentation -> recording rule evaluator -> persisted SLI series -> incident timeline includes recorded metrics snapshots. Step-by-step implementation:

  • Identify SLI used by incident alerts.
  • Ensure recording rule exists and retention covers postmortem window.
  • Backfill missing historical SLI points where possible.
  • Use recorded series in timeline and blame-free postmortem. What to measure:

  • Backfill success, SLI agreement diff. Tools to use and why:

  • TSDB with backfill capability and audit logs. Common pitfalls:

  • Retention too short to support postmortem analysis. Validation:

  • Conduct a mock incident and confirm SLI audit trail. Outcome:

  • Faster, clearer postmortems and actionable remediation.

Scenario #4 — Cost vs performance trade-off for high-cardinality telemetry

Context: Team wants to precompute many derived metrics but storage cost increases. Goal: Balance query performance with storage cost. Why Recording rule matters here: Precomputation speeds queries but increases series count and storage. Architecture / workflow: Metric pipeline -> rule evaluator -> TSDB -> dashboards -> cost monitoring. Step-by-step implementation:

  • Inventory proposed recording rules and estimate series growth.
  • Simulate cost delta with sample data.
  • Prioritize rules by reuse and business impact.
  • Implement label normalization and cardinality caps.
  • Deploy slowly and monitor created series and storage. What to measure:

  • Created series count, storage growth, query latency improvement, cost per query. Tools to use and why:

  • Cost allocation tooling, TSDB metrics, CI cardinality tools. Common pitfalls:

  • Unbounded label values introduced by user input causing runaway cost. Validation:

  • Canary deploy rules and monitor resource and cost signals. Outcome:

  • Targeted set of recording rules delivering benefits without excessive cost.


Common Mistakes, Anti-patterns, and Troubleshooting

Format: Symptom -> Root cause -> Fix

  1. Symptom: TSDB OOMs after rule deploy -> Root cause: Unbounded labels in rule -> Fix: Normalize or drop labels.
  2. Symptom: Recorded SLI diverges from raw computation -> Root cause: Wrong aggregation window -> Fix: Align windows and rerun tests.
  3. Symptom: Duplicate series points -> Root cause: Multiple evaluators without leader election -> Fix: Configure leader election/dedupe.
  4. Symptom: High query latency remains -> Root cause: Recording rules not covering heavy queries -> Fix: Identify heavy queries and create targeted rules.
  5. Symptom: Eval jobs fail intermittently -> Root cause: Upstream partial responses or shard failures -> Fix: Monitor partial response and add retries.
  6. Symptom: Alert flapping after rule switch -> Root cause: Different sampling/interval between raw and recorded -> Fix: Smooth or align alert thresholds.
  7. Symptom: Unexpected cost spike -> Root cause: New rule created many series -> Fix: Rollback and apply cardinality controls.
  8. Symptom: No historical data in postmortem -> Root cause: Retention policy too short for recorded series -> Fix: Extend retention or backfill.
  9. Symptom: False positives in security alerts -> Root cause: Bad label normalization grouping different users -> Fix: Refine grouping keys.
  10. Symptom: Rule changes cause downtime -> Root cause: Rules deployed without canary testing -> Fix: Add canary stages in CI/CD.
  11. Symptom: CI lint fails late -> Root cause: No early cardinality estimation -> Fix: Add cardinality checks in PR pipeline.
  12. Symptom: Confusion over metric naming -> Root cause: No naming convention or registry -> Fix: Create naming standards and catalog.
  13. Symptom: Rule produces empty series -> Root cause: Filter too narrow or label mismatch -> Fix: Check input labels and broaden selection.
  14. Symptom: Slow backfill -> Root cause: Unoptimized backfill process -> Fix: Batch backfills and monitor write throughput.
  15. Symptom: Missing ownership for rules -> Root cause: No governance -> Fix: Assign owners and require approval.
  16. Symptom: Dashboard discrepancies -> Root cause: Mixed use of raw and recorded series -> Fix: Standardize to recorded where intended.
  17. Symptom: High eval CPU spikes at rollout -> Root cause: All rules evaluate simultaneously after deploy -> Fix: Stagger or randomize evaluation start times.
  18. Symptom: No alert when evaluators die -> Root cause: No monitoring on evaluator process -> Fix: Export evaluator health metrics.
  19. Symptom: Duplicate alerts across teams -> Root cause: Multiple teams using slightly different recorded metrics -> Fix: Consolidate SLI definitions.
  20. Symptom: Rule tests pass locally but fail in cluster -> Root cause: Different metric ingestion or label set in prod -> Fix: Test with representative production-like data.
  21. Symptom: Ineffective SLOs -> Root cause: Incorrect SLI choice or noisy metric -> Fix: Re-evaluate SLI and possibly smooth series.
  22. Symptom: Recording rule impacts feature rollout -> Root cause: Tight coupling between feature flag and metric label -> Fix: Decouple metric labels from transient flags.
  23. Symptom: Metrics missing from dashboards after upgrade -> Root cause: Metric renaming without aliasing -> Fix: Provide compatibility aliases and migration steps.
  24. Symptom: High cardinality from user agent strings -> Root cause: Free-form label in rule -> Fix: Hash or bucketize user agent values.
  25. Symptom: Observability pipeline lag -> Root cause: Heavy evaluation loads -> Fix: Rate-limit evaluations and add resource quotas.

Observability pitfalls (at least 5 included above)

  • Using raw ad-hoc queries as canonical SLI.
  • Failing to monitor evaluator health.
  • Ignoring cardinality impacts.
  • Not backfilling recorded series.
  • Lack of audit trail for rule changes.

Best Practices & Operating Model

Ownership and on-call

  • Assign rule owners and SLO owners.
  • Include recording rule health on-call rotations for the SLO owner.
  • Separate infra on-call for evaluator platform.

Runbooks vs playbooks

  • Runbooks: specific remediation steps for rule failures.
  • Playbooks: higher-level incident strategy for SLO breaches.

Safe deployments

  • Canary new rules in test and canary clusters.
  • Gradual rollout with resource and metric gate checks.
  • Automate rollback on cardinality or CPU anomalies.

Toil reduction and automation

  • CI linting and cardinality checks.
  • Automated backfill and migrations.
  • Auto-remediation scripts for common failures.

Security basics

  • Ensure rule configs stored in version-controlled repos with access control.
  • Audit changes and enable immutable logging.
  • Avoid embedding secrets in rule expressions.

Weekly/monthly routines

  • Weekly: Review eval success, top consuming rules, and alert counts.
  • Monthly: Audit rule ownership and retirement candidates.
  • Quarterly: Review SLO targets and rule impact on cost.

Postmortem reviews

  • Review if recorded series were used and accurate.
  • Check if runbooks triggered and mitigations were effective.
  • Update rule configs and tests based on findings.

Tooling & Integration Map for Recording rule (TABLE REQUIRED)

ID Category What it does Key integrations Notes
I1 TSDB Stores recorded series Grafana alerting CI systems Choose one that handles cardinality
I2 Rule evaluator Runs and writes recordings TSDB storage and discovery Needs leader election
I3 CI/CD Lints and deploys rules Git repos and pipelines Enforce tests and approvals
I4 Dashboarding Visualizes recorded series Alerts and SLO engines Use recorded metrics as canonical
I5 Cost tooling Tracks storage and CPU cost Billing tags and owners Map metrics to teams
I6 Cardinality tool Estimates series growth CI and predeploy checks Prevents unexpected explosion
I7 Backfill tool Write historical points TSDB APIs and storage Must dedupe and validate
I8 Access control Manage rule change rights IAM and git auth Enforce least privilege
I9 Audit logs Tracks changes and deploys SIEM and logging Important for compliance
I10 Alerting engine Pages based on recorded SLIs On-call and paging services Tie to burn-rate logic

Row Details (only if needed)

  • None.

Frequently Asked Questions (FAQs)

What is the primary benefit of a recording rule?

Reduces query latency and ensures consistent, auditable metrics for SLIs and dashboards.

Do recording rules change raw metric retention?

No, they add new series that follow their own retention policy; retention must be configured separately.

How often should recording rules evaluate?

Depends on SLO accuracy needs; common defaults are 15s to 1m for infra, 1m to 5m for business metrics.

Can recording rules cause high cardinality?

Yes; unbounded labels or per-entity aggregations can explode series count.

Should every expensive query be converted to a recording rule?

Not always; prioritize by reuse and business impact.

How do I backfill a recording rule?

Use TSDB backfill APIs or tooling to write historical points; ensure deduplication.

Are recording rules secure?

Their configs should be stored in VCS with strict access control and audit logging.

Do cloud providers offer managed recording rules?

Some do; features and limits vary by provider. Varies / depends.

How to test recording rules before production?

Unit tests comparing raw and recorded results, canary deployments, and CI cardinality checks.

Who owns recording rules in an org?

SLO owners and platform teams jointly; ownership must be explicit.

What happens when a rule is removed?

Recorded series may become orphaned; consider deprecation policy and cleanup.

Can recording rules be versioned?

Yes; version in code and use migrations or aliases to avoid metric disruptions.

How to avoid noisy alerts from recorded series?

Tune alert thresholds, use grouping, and ensure SLI smoothing matches expectations.

Are recording rules resource intensive?

They can be; monitor evaluator CPU and memory and rate-limit as needed.

How to measure impact of adding a recording rule?

Track query latency before/after, evaluator CPU, created series, and storage delta.

Should recording rules be created per-tenant?

Only when necessary; consider aggregated per-tenant rollups to limit cardinality.

How to deprecate a recording rule safely?

Mark deprecated, stop consumers gradually, and delete after confirmation and waiting period.

What is the audit requirement for recording rules in regulated environments?

Keep change history and access logs; retention policies may be required. Varied by regulation.


Conclusion

Recording rules are a foundational pattern for reliable, performant, and auditable observability. When used with governance, CI checks, and careful label management, they reduce toil and improve SLO reliability while controlling cost.

Next 7 days plan

  • Day 1: Inventory existing heavy queries and candidate rules.
  • Day 2: Add recording rule lint and cardinality checks to CI.
  • Day 3: Implement one canonical SLI as a recording rule and test in canary.
  • Day 4: Create dashboards and switch one on-call dashboard to use the recorded SLI.
  • Day 5: Monitor evaluator health, storage impact, and adjust retention.
  • Day 6: Run a small load test and validate metrics and alerts.
  • Day 7: Document ownership, add runbook, and schedule weekly reviews.

Appendix — Recording rule Keyword Cluster (SEO)

  • Primary keywords
  • recording rule
  • recording rules
  • metric recording rule
  • precomputed metric
  • recorded metric
  • Prometheus recording rule
  • recording rule best practices
  • recording rule guide

  • Secondary keywords

  • TSDB recording rule
  • rule evaluator
  • evaluators for recording rules
  • recording rule cardinality
  • recording rule retention
  • recording rule architecture
  • recording rule troubleshooting
  • recording rule CI/CD

  • Long-tail questions

  • what is a recording rule in observability
  • how do recording rules improve performance
  • when should I use a recording rule
  • how to prevent cardinality explosion from recording rules
  • how to test a recording rule in CI
  • how to backfill recording rule data
  • how to measure impact of recording rules
  • how to version recording rules
  • can recording rules cause OOM in TSDB
  • how to roll back a recording rule deployment
  • recording rule vs alerting rule differences
  • how often should recording rules evaluate
  • recording rule for SLIs and SLOs
  • cost of recording rules in cloud monitoring
  • how to normalize labels for recording rules

  • Related terminology

  • time-series database
  • TSDB
  • labels and cardinality
  • aggregation window
  • SLI SLO error budget
  • histogram rollup
  • backfill
  • materialized view for metrics
  • remote write
  • leader election
  • evaluator latency
  • query latency reduction
  • cardinality estimation
  • retention policy
  • canary deployment
  • CI linting for metrics
  • observability pipeline
  • metric normalization
  • derived metric
  • rollup rules
  • deduplication
  • audit trail
  • cost allocation
  • storage growth
  • evaluator health
  • alert grouping
  • burn rate escalation
  • runbook for recording rules
  • playbook vs runbook
  • platform observability
  • managed recording rules
  • cloud-native metrics
  • serverless metrics
  • kubernetes metrics
  • PromQL recording rules
  • Thanos Thanos ruler
  • Cortex Mimir rules
  • prometheus rule files
  • rule versioning
  • rule retirement
  • SLO enforcement with recording rules