Introduction

Reduces the Redis maxmemory configuration to force key evictions or OOM errors on a Redis instance. The original maxmemory and eviction policy are automatically restored when the attack ends.

Combine with Memory Usage Check to monitor the impact of the reduced memory limit during the experiment. For connection-level faults, use Exhaust Connections instead.

Warning: Using eviction policies like allkeys-lru, allkeys-lfu, or allkeys-random will permanently delete keys when the memory limit is reached. Evicted data cannot be recovered. The default policy noeviction is the safest choice as it returns OOM errors instead of deleting data.

Use Cases

• Force key evictions to verify that the application handles missing cache keys gracefully and rebuilds them.
• Test OOM behavior by reducing maxmemory below current usage and verifying the application handles write errors.
• Validate that eviction-policy-aware applications degrade correctly under memory pressure.

Parameters

Parameter	Description	Default
Duration	How long to apply the reduced memory limit. Original config is restored when the duration expires.	60s
Max Memory	Memory limit to set (e.g., 10mb, 1gb, or a value in bytes). Set this below current usage to trigger immediate evictions or OOM errors.	10mb
Eviction Policy	Eviction policy to apply while the limit is active. Valid values: noeviction (return errors on writes), allkeys-lru, allkeys-lfu, allkeys-random (evict from all keys), volatile-lru, volatile-ttl (evict from keys with TTL), keep (keep the original policy). Caution: allkeys-* policies permanently delete data.	noeviction