Tair (Redis® OSS-Compatible):Configuration parameter list for Tair Enterprise Edition

Enabling this feature increases CPU usage by more than 5%, proportional to the number of keys.<br><br>- #no_loose_high-cost-key-enabled: Enables the feature. Default: no. Set to yes to enable.<br>- #no_loose_high-cost-key-traffic-bytes-threshold: Access traffic threshold (bytes/s) for reporting a hot key. Valid values: [1024–4294967295]. Default: 1048576 (1 MB/s).<br>- #no_loose_high-cost-key-parse-hashtag: Aggregates keys sharing the same {hashtag}. If their combined traffic exceeds the threshold, the hashtag is reported as a hot key. Default: no.<br> Example: {user}a and {user}b are not individually hot keys, but if their aggregated traffic exceeds the threshold, Top Key Statistics marks {user} as a hot key of the Hashtag type.<br>- #no_loose_high-cost-key-parse-prefix: Aggregates keys sharing the same prefix. Default: no.<br> - #no_loose_high-cost-key-parse-prefix-delimiters: Characters used as separators. Default: empty. Multiple characters (e.g., : _) are each treated as individual separators.<br> - #no_loose_high-cost-key-parse-prefix-skip-first-n: Number of leading separators to skip. Valid values: [0–5]. Default: 0.<br> - #no_loose_high-cost-key-parse-prefix-find-limit-n: Maximum depth (segments) to extract as a prefix. Valid values: [1–5]. Default: 1.<br> Example: For keys service:user:123 and service:user:456 with separator : — if skip-first-n is 1 and find-limit-n is 1, the hot key service:user is captured; if skip-first-n is 0 and find-limit-n is 2, both service and service:user are captured.<br><br>

Commands configured here can be run without authentication on any connection. Enter commands in lowercase, separated by commas.

<br>- Only memory-optimized instances compatible with Redis 6.0 or later support client-output-buffer-limit normal.<br>- The client output buffer consumes runtime memory. If too many commands accumulate, it can trigger data eviction or cause an out-of-memory failure. Review your instance's memory specification before adjusting these values.

The value must contain at least K or E; otherwise no notifications are sent.<br><br>Use any combination of the following characters:<br>- K: Keyspace notifications (prefixed with __keyspace@<db>__).<br>- E: Key-event notifications (prefixed with __keyevent@<db>__).<br>- g: Generic commands (DEL, EXPIRE, RENAME, etc.).<br>- $: String commands.<br>- l: List commands.<br>- s: Set commands.<br>- h: Hash commands.<br>- z: Sorted set commands.<br>- x: Expired events (sent when an expired key is deleted).<br>- e: Evicted events (sent when a key is deleted by the eviction policy).<br>- A: Alias for g$lshzxe — subscribes to all of the above.<br><br>Example: To receive expiration events, set this parameter to Ex, then run PSUBSCRIBE __keyevent@0__* on the client to subscribe to key-event notifications for DB0.

Cached key-value data is not updated during the cache validity period. Confirm your workload can tolerate eventual consistency before enabling.<br><br>- query_cache_enabled: Enables the feature. Default: 0 (disabled). Set to 1 to enable.<br>- query_cache_expire: Cache validity period in milliseconds. Valid values: [100–60000]. Default: 1000. A shorter value reduces cache hit rate; a longer value increases the window during which clients read stale data.<br>- query_cache_mode: Working mode.<br> - 0 (default): Caches only hot keys pushed by data shards.<br> - 1: Caches all keys using LRU (least recently used) eviction. Because each proxy thread has a 100 MB cache limit, LRU eviction may reduce hit rate and overall performance.