Redis Observability

Redis Observability

What to watch, what to run, and what to alert on. Covers the metrics every Redis deployment should monitor and the built-in commands for ad-hoc diagnosis.

When to apply

• Setting up monitoring or alerts for a Redis instance.
• Diagnosing a Redis performance regression (high latency, memory pressure, connection storms).
• Profiling a slow FT.SEARCH or pipeline.
• Wiring Redis metrics into Prometheus, Datadog, CloudWatch, or similar.

1. Monitor these metrics

These come from INFO and should be exported to your monitoring system.

info = redis.info()
hit_ratio = info["keyspace_hits"] / max(1, info["keyspace_hits"] + info["keyspace_misses"])
print(f"Memory:    {info['used_memory_human']}")
print(f"Clients:   {info['connected_clients']}")
print(f"Ops/sec:   {info['instantaneous_ops_per_sec']}")
print(f"Hit ratio: {hit_ratio:.1%}")

See references/metrics.md.

2. Built-in commands for debugging

Reach for these when something looks off.

The two most useful for incident triage:

• `SLOWLOG GET` to find queries that exceeded the slowlog-log-slower-than threshold (10ms by default). The output shows the exact command and duration in microseconds.
• `MEMORY DOCTOR` for memory pressure — it returns a one-paragraph summary of what's unusual about memory usage right now.

for entry in redis.slowlog_get(10):
    print(f"{entry['duration']}μs  {entry['command']}")

See references/commands.md.

3. Redis Insight

For interactive use (running queries, browsing keys, profiling indexes), Redis Insight is the official GUI. It surfaces the same SLOWLOG / INFO / FT.PROFILE data visually and includes Redis Copilot for natural-language queries. Useful during development and incident response; not a replacement for exporting metrics to your monitoring system.

References

• Redis: Latency monitoring
• Redis Insight

Use Observability Commands for Debugging

Redis provides built-in commands for monitoring and debugging.

Key commands:

# Slow query log - find slow commands
SLOWLOG GET 10
SLOWLOG LEN
SLOWLOG RESET

# Server info - comprehensive stats
INFO all
INFO memory
INFO stats
INFO replication
INFO clients

# Memory analysis
MEMORY DOCTOR
MEMORY STATS
MEMORY USAGE mykey

# Client connections
CLIENT LIST
CLIENT INFO

# Index info (RQE)
FT.INFO idx:products
FT.PROFILE idx:products SEARCH QUERY "@name:laptop"

Correct: Check SLOWLOG regularly.

# Get recent slow queries
slow_queries = redis.slowlog_get(10)
for query in slow_queries:
    print(f"Duration: {query['duration']}μs, Command: {query['command']}")

Reference: Redis Monitoring

Monitor Key Redis Metrics

Track these metrics to catch issues before they impact users.

Correct: Export metrics to your monitoring system.

# Get key metrics
info = redis.info()
print(f"Memory: {info['used_memory_human']}")
print(f"Connections: {info['connected_clients']}")
print(f"Ops/sec: {info['instantaneous_ops_per_sec']}")
print(f"Hit ratio: {info['keyspace_hits'] / (info['keyspace_hits'] + info['keyspace_misses']) * 100:.1f}%")

Redis Insight: Use Redis Insight for visual monitoring, query profiling, and debugging. It includes Redis Copilot for natural language queries.

Reference: Redis Insight