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low_level_race_condition_ttl

⚡ Low-Level Caching with Race-Condition TTL​

For high-traffic endpoints where cache stampedes are a concern, use race_condition_ttl to prevent multiple processes from recomputing stale data concurrently. This option lets an expired entry remain valid for a short grace period while a single request refreshes it.

# Fetch or compute a heavy payload
Rails.cache.fetch("heavy_report", expires_in: 1.hour, race_condition_ttl: 10.seconds) do
  compute_heavy_report
end

This ensures if the cache expires, the first process enters the block and others use the stale value for up to 10 seconds, drastically reducing DB load.