When Redis changed its license in 2024, engineering teams faced a real choice: stay on Redis under SSPL terms, or migrate to Valkey — the Linux Foundation fork preserving BSD licensing. By mid-2025, both Redis 8 and Valkey 8 have shipped. The licensing question is no longer the only factor.
This guide compares Redis 8 and Valkey 8 on performance, persistence, cluster behavior, new features, and licensing risk — the dimensions that actually matter in production.
- Valkey 8 is BSD-licensed under the Linux Foundation — safe for SaaS and cloud providers.
- Redis 8 ships native vector search and JSON, reducing module dependencies.
- Valkey 8 enables multi-threaded I/O by default — 30-50% throughput gains for large-value workloads.
- Both are wire-compatible with Redis 7 clients — migration is a config swap, not a code change.
Licensing: The Decisive Difference
| Aspect | Redis 8 | Valkey 8 |
|---|---|---|
| License | SSPL + RSALv2 | BSD 3-Clause |
| Governance | Redis Ltd. | Linux Foundation |
| Cloud provider support | Not permitted under SSPL | AWS, GCP, Azure supported |
| Self-hosted commercial use | Restricted by SSPL | Unrestricted |
| AWS ElastiCache support | No | Yes (Valkey engine) |
The SSPL requires that if you offer Redis as a service, you must open-source your entire service stack. SaaS companies building on Redis should audit with legal counsel before upgrading to Redis 8.
New Features in Redis 8
Native Vector Search
Redis 8 integrates vector similarity search natively — previously only via the RedisSearch module. This enables KNN search without loading additional modules:
FT.CREATE idx:embeddings ON HASH PREFIX 1 doc:
SCHEMA embedding VECTOR HNSW 6
TYPE FLOAT32 DIM 1536 DISTANCE_METRIC COSINE
FT.SEARCH idx:embeddings "*=>[KNN 10 @embedding $blob]"
PARAMS 2 blob "..." DIALECT 2Dual-Channel Replication
Redis 8 uses a dedicated channel for RDB transfers, separate from command replication. This eliminates the replication lag spikes previously seen during full sync of large datasets — a major pain point in Redis 7 clusters over 50GB.
New Features in Valkey 8
I/O Threading Enabled by Default
Valkey 8 enables multi-threaded I/O by default, delivering 30-50% throughput gains for I/O-bound workloads without any configuration change:
# valkey.conf — Valkey 8 defaults
io-threads 4
io-threads-do-reads yes
# Verify threading is active
valkey-cli INFO server | grep io_threads_activeCluster Bus Efficiency
Slot migration in large clusters (>100 nodes) that took 20+ minutes in Redis 7 completes in under 5 minutes in Valkey 8, with improved cluster bus protocol reducing gossip overhead by ~40%.
Performance Benchmarks
| Workload | Redis 8 | Valkey 8 |
|---|---|---|
| SET/GET small values (single-threaded) | ~1.1M ops/s | ~1.1M ops/s |
| Large value reads (100KB, I/O bound) | ~280K ops/s | ~380K ops/s (+35%) |
| Pub/Sub throughput | ~900K msg/s | ~950K msg/s |
| ZADD/ZRANGE (sorted sets) | ~650K ops/s | ~640K ops/s |
| Vector KNN search (1536-dim, 1M vectors) | ~4.2ms p99 | Not yet native |
Run redis-benchmark (works with both servers) against your actual access patterns. Synthetic benchmarks rarely match production read/write/pipeline ratios on real workloads.
Migration Path
# Rolling migration from Redis 7 to Valkey 8
# 1. Add Valkey 8 replica to existing Redis 7 primary
valkey-server --replicaof redis-primary 6379 --port 6380
# 2. Verify replication lag is zero
valkey-cli -p 6380 INFO replication | grep master_repl_offset
# 3. Promote Valkey replica and update application DNS
valkey-cli -p 6380 REPLICAOF NO ONEWhich to Choose
Choose Redis 8 if: you need native vector search, you are on Redis Enterprise, or legal has cleared SSPL for your use case and you want commercial support from Redis Ltd.
Choose Valkey 8 if: you run on AWS ElastiCache, you have a SaaS product, you want Linux Foundation governance, or you need multi-threaded I/O gains for large-value workloads.
- Valkey 8 is BSD-licensed and production-ready — safe default for new projects and SaaS products.
- Redis 8 leads on native vector search and has a clear enterprise support path via Redis Ltd.
- Multi-threaded I/O in Valkey 8 delivers real throughput gains for I/O-bound workloads — benchmark your specific pattern.
- Both are wire-compatible with Redis 7 clients — migration requires no application code changes.
Working with JusDB on In-Memory Databases
JusDB helps engineering teams evaluate Redis vs Valkey, migrate between versions with zero downtime, and tune persistence and cluster configuration. We have migrated teams from Redis 7 to Valkey 8 using rolling replica upgrades without any service interruption.