CONFIG SET

Sets configuration parameters in-flight.

Browse all commands · Upstream source documentation

Reference field	Value
Canonical name	CONFIG SET
Catalog group	Server commands
Upstream since	2.0.0 — upstream Redis/module version, not an ffkv release
Pinned catalog	Redis 8.10.0

Syntax

CONFIG SET parameter value [parameter value ...]

ffkv behavior and limits

Server introspection describes ffkv, not a Redis process. MEMORY reports owned-allocation estimates, not jemalloc accounting. Administrative changes can affect all clients or persistent data; consult the scenario and operations guide before using destructive forms.

Source: README.md:393–395, 601–642; tests/bdd/features/server.feature; tests/bdd/features/catalog.feature.

All requests share the 8 MiB framing/1,024-argument ingress limit; normal RESP replies have 64 MiB wire/logical budgets with bounded nesting/value counts. Management and Lua origins impose smaller budgets. These are not a process RSS cap. Catalog inclusion is not exhaustive option or wire-format parity. See limits and compatibility.

Upstream metadata

The following fields come from the pinned Redis metadata, not measured ffkv performance or an assertion that ffkv enforces every upstream flag. Running COMMAND INFO/COMMAND DOCS describe the current engine.

Upstream Redis complexity: O(N) when N is the number of configuration parameters provided

Upstream arity: -4 (includes the command name; a negative number is a minimum).

Command flags: ADMIN, NOSCRIPT, LOADING, STALE.

Command tips: REQUEST_POLICY:ALL_NODES, RESPONSE_POLICY:ALL_SUCCEEDED.

Argument structure

Argument	Type	Constraints / metadata
data	block	multiple
↳ parameter	string	Required
↳ value	string	Required

Additional pinned upstream metadata

{
  "group": "server",
  "since": "2.0.0",
  "history": [
    [
      "7.0.0",
      "Added the ability to set multiple parameters in one call."
    ]
  ]
}

Metadata source · Local snapshot: src/command_metadata.json, key config|set.

BDD coverage and source examples

These are source observations, not a test run performed by this documentation build. A tag identifies scenario intent; an extracted vector identifies a command invocation, which may intentionally produce an error. Scenarios may require setup, multiple connections, persistence, cluster nodes or native-module fixtures.

• Configuration updates validate the complete transaction before publication — tests/bdd/features/server.feature:5; command tag and invocation observed.
• Rewritten effective configuration is loaded after a crash — tests/bdd/features/server.feature:39; invocation observed.
• Latency history and diagnostics reflect a recorded execution delay — tests/bdd/features/server.feature:370; invocation observed.
• Slow log contains actual command arguments and reset removes them — tests/bdd/features/server.feature:412; invocation observed.
• Transactional configuration publishes effective values and observations do not repause engines — tests/bdd/features/transactions_runtime.feature:5; command tag and invocation observed.
• AOF configuration inside EXEC preserves the saved committed prefix exactly once — tests/bdd/features/transactions_runtime.feature:66; command tag and invocation observed.

Extracted command vectors

The following JSON arrays are the test harness’s argument vectors, not shell commands. Numeric arguments are converted by the harness; objects of the form {"base64":"…"} represent decoded binary bytes, not a literal JSON command argument. Preserve scenario setup and connection ordering. See the CLI guide for shell quoting and binary stdin. No reply is invented or inferred.

Transactional configuration publishes effective values and observations do not repause engines — tests/bdd/features/transactions_runtime.feature:16 (client “admin” executes:)

[
  "CONFIG",
  "SET",
  "maxclients",
  "4096",
  "slowlog-max-len",
  "31"
]

Next source assertion: the reply equals:

"QUEUED"

Configuration updates validate the complete transaction before publication — tests/bdd/features/server.feature:8 (I execute:)

[
  "CONFIG",
  "SET",
  "latency-monitor-threshold",
  "7",
  "slowlog-max-len",
  "9"
]

Next source assertion: the reply equals:

"OK"

AOF configuration inside EXEC preserves the saved committed prefix exactly once — tests/bdd/features/transactions_runtime.feature:68 (the following commands succeed:)

[
  "CONFIG",
  "SET",
  "appendonly",
  "no"
]