Redis Knowledge Patch

Redis Knowledge Patch

Use this skill when upgrading, securing, configuring, or developing against Redis Open Source. Determine the deployed release and topology first, check the security floors, and then open the topic reference that matches the task.

Reference index

Working method

1. Identify the exact Redis release, standalone or clustered topology, persistence mode, and whether the deployment came from Redis Stack or standalone modules.
2. Apply the security floor for the deployed minor line. Do not substitute a similarly numbered patch from a different minor line.
3. Re-audit ACL categories and key patterns when moving to integrated Search, JSON, Time Series, or probabilistic components.
4. Check persistence and migration caveats before using stream idempotency, slot migration, or node-side backup and restore.
5. Open the relevant reference before implementing an affected command; the quick reference deliberately compresses restrictions and maintenance floors.

Breaking, security, and compatibility checks

Patch security-sensitive deployments first

Use at least the fixed release shown for the deployed minor line.

The five-path RCE group spans client unblock, RESTORE, Lua, Time Series, and probabilistic structures. The 8.10.1 fixes span CMSketch, TopK, TLS, SLOT_INFO, Vector Set, and blocked-client paths; a crafted SLOT_INFO case may allow RCE. Read the security reference for the full scope.

Re-audit ACLs after component integration

Search, JSON, Time Series, Bloom, Cuckoo, Count-min sketch, Top-k, and t-digest are integral components. Broad categories such as @read and @write include their commands. Use @search, @json, @timeseries, @bloom, @cuckoo, @cms, @topk, and @tdigest where narrower access is intended.

Search index access additionally requires key patterns that cover a superset of the index prefixes. Multi-key Time Series reads fail if any matching key is unreadable, while TS.QUERYINDEX reads metadata without requiring access to the matched keys.

Plan module-era upgrades explicitly

Binary distributions include the integrated components, and redis-full.conf loads all of them; Vector Set remains preview in the integration guidance. Replication or persistence upgrades are supported from module-free Redis, deployments using the former standalone modules, and Redis Stack 7.2 or 7.4. Account for packaging and ACL expansion in the migration plan.

Remove obsolete vector assumptions

Redis Open Source no longer has proprietary LeanVec or LVQ Intel optimizations from 8.2.1 onward. Use the compressed SVS-VAMANA index introduced in 8.2; 8.2.2 permits BUILD_INTEL_SVS_OPT for Intel optimizations.

Respect stream persistence and cluster-query caveats

XADD IDMPAUTO and IDMP provide at-most-once production. On 8.6.0, do not combine them with appendonly yes and aof-use-rdb-preamble no; 8.6.2 fixes AOF rewrite and restoration of idempotency state.

CLUSTER MIGRATION moves slots atomically, but affected Search and Time Series multi-key queries can still return partial or duplicate results during the migration. Atomic slot movement does not make those query results atomic.

High-value command changes

Strings, hashes, and counters

• DIGEST, DELEX, and SET extensions support atomic compare-and-set and compare-and-delete flows on string keys.
• MSETEX atomically sets multiple string keys and updates their expiration.
• INCREX combines integer or floating-point increments, bounds, and expiration for window-counter rate limiting.
• Compact hashes store shared field names once for repeated schemas, and HIMPORT provides high-throughput bulk insertion for them.

Lists, sets, and bit operations

• LMOVEM and blocking BLMOVEM move multiple list elements.
• SUNIONCARD and SDIFFCARD return union and difference cardinality.
• BITOP accepts DIFF, DIFF1, ANDOR, and ONE.
• ZUNION, ZINTER, ZUNIONSTORE, and ZINTERSTORE accept the COUNT aggregator.

Streams

• XDELEX, XACKDEL, and extensions to XADD and XTRIM add DELREF and ACKED reference strategies.
• XREADGROUP CLAIM min-idle-time can return sufficiently idle pending entries and incoming entries in one read.
• XNACK lets a consumer explicitly release pending messages.
• XREAD and XREADGROUP accept MAXCOUNT and MAXSIZE to cap cumulative reply entry count and size.

Core structures and notifications

• Array is a data structure.
• OVERWRITTEN reports complete value replacement, TYPE_CHANGED reports a key type change, and hash subkey notifications provide field-level events.
• Replicated CF.LOADCHUNK chunks prevent silent Cuckoo Filter loss after failover on the fixed maintenance releases.

Search, JSON, and Time Series

Vector and hybrid search

• VSIM WITHATTRIBS returns an element's JSON attribute, while EPSILON sets a maximum distance.
• FT.HYBRID combines results with RRF or LINEAR scoring. In its original behavior, post-COMBINE filtering is unavailable; default output contains only key_id and score; and EXPLAINSCORE, YIELD_DISTANCE_AS, and WITHCURSOR are unsupported.
• The KNN clause can request fewer candidates per shard, and FT.PROFILE HYBRID profiles hybrid queries.
• search-default-scorer sets the default text and tag scorer; BM25STD is the new default.
• FT.ALIASLIST enumerates aliases, Malay and Tagalog stemming is available, and FT.CREATE and FT.ALTER reject empty field names.

JSON and Time Series

• JSON.SET FPHA selects the floating-point type for a homogeneous floating-point array.
• Range commands can apply multiple aggregators in one request. Time Series accepts NaN values and provides COUNTNAN and COUNTALL.
• TS.NRANGE and TS.NREVRANGE group multi-series results by timestamp; TS.READ supports optional blocking reads; and TS.QUERYLABELS discovers labels and their values.
• TS.MRANGE and TS.MREVRANGE accept EXCLUDEEMPTY to omit series with no samples.

Operations quick reference

• Runtime memory tracking can be enabled only in non-clustered mode.
• volatile-lrm and allkeys-lrm select least-recently-modified eviction.
• HOTKEYS detects hot keys; HOTKEYS HELP is available from 8.6.1.
• INFO KEYSIZES reports size distributions for basic types, while CLUSTER SLOT-STATS reports per-slot key count, CPU time, and network I/O.
• key-memory-histograms collects per-type memory histograms and exposes database distribution metrics for lists, sets, hashes, and sorted sets.
• BACKUP provides node-side backup and restore based on multi-part AOF.
• Modules can read and write Redis configuration and selectively unsubscribe from keyspace notifications.
• tls-auth-clients-user enables client certificate authentication; failed attempts increment acl_access_denied_tls_cert. Server-to-server TLS can also authenticate peers by certificate.

Read the indexed reference before implementing an affected feature. It records the exact command scope, maintenance floors, and topology-specific constraints.