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PCACHE.CREATE

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PCACHE.CREATE namespace [MAX_ENTRIES n] [TTL seconds] [COST_PER_HIT usd]
Group
Prompt cache
Complexity
O(1)
Arity
-2 (at least 2 words, counting the command name)
Flags
write, fast
Keys
first 1, last 1, step 1
HotKV Cloud
Performance and Scale
On-Premise
requires the prompt-cache license feature

The prompt cache is an exact-match cache for LLM prompt and response pairs, organised in named namespaces. PCACHE.CREATE creates a namespace. You must create a namespace before you can store entries in it with PCACHE.SET.

Options

Section titled “Options”
Option Effect
MAX_ENTRIES n Maximum number of entries. 0 or omitted uses the server’s per-namespace limit, and larger values are capped at that limit (max_entries_per_namespace under [pcache]). When the namespace is full, HotKV evicts existing entries to make room, expired entries first.
TTL seconds Default time to live for entries stored without their own TTL. 0 or omitted means entries do not expire.
COST_PER_HIT usd A fixed dollar amount credited to cost_saved_usd in PCACHE.STATS for every hit. Must be zero or positive. Default 0.

Options can be given in any order and are case-insensitive. You can change all three later with PCACHE.CONFIG.

Return value

Section titled “Return value”
Case RESP2 RESP3
Namespace created Simple string OK Same

Errors:

  • ERR namespace already exists or limit reached if the namespace exists, or the server already holds its maximum number of prompt cache namespaces (max_namespaces under [pcache]).
  • ERR invalid MAX_ENTRIES, ERR invalid TTL or ERR invalid COST_PER_HIT if a value cannot be parsed or is negative.
  • ERR unknown option for any other option name.
  • ERR wrong number of arguments for 'pcache.create' command if the argument count is wrong.
  • NOLICENSE prompt-cache requires a HotKV license. Contact sales@hotkv.com if your license does not include the prompt-cache feature.

Examples

Section titled “Examples”
127.0.0.1:6379> PCACHE.CREATE llm_prompts MAX_ENTRIES 100000 TTL 3600 COST_PER_HIT 0.012
OK
127.0.0.1:6379> PCACHE.CREATE llm_prompts
(error) ERR namespace already exists or limit reached

Compatibility

Section titled “Compatibility”

HotKV-only command. Redis and Valkey have no equivalent.

See also

Section titled “See also”

PCACHE.SET, PCACHE.GET, PCACHE.GETEX, PCACHE.DEL, PCACHE.STATS, PCACHE.FLUSH, PCACHE.DROP, PCACHE.LIST, PCACHE.CONFIG, AI features guide