Releases · redis/redis

@brandur

This is the second Milestone of Redis 8.8 in Redis Open Source.

Milestones are non-feature-complete pre-releases. Pre-releases are not suitable for production use.

Headlines:

Redis 8.8 introduces new features and performance improvements.

8.8-M02 is available as a Docker image and can be downloaded from Docker Hub. Additional distributions will be introduced in upcoming pre-releases.

Operating systems we test Redis 8.8 on

Ubuntu 22.04 (Jammy Jellyfish), 24.04 (Noble Numbat), 26.04 (Resolute Raccoon)
Rocky Linux 8.10, 9.7, 10.1
AlmaLinux 8.10, 9.7, 10.1
Debian 12.13 (Bookworm), Debian 13.4 (Trixie)
Alpine 3.23
macOS 14.8.4 (Sonoma), 15.7.4 (Sequoia), 26.3 (Tahoe) - for both Intel and ARM

New Features (compared to 8.6)

#14826, #14905 GCRA (generic cell rate algorithm) rate limiter (based on the redis-cell module by @brandur - thank you!)
#14797 XNACK: a new streams command that allows consumers to explicitly release pending messages
RedisJSON/RedisJSON#1509 JSON.SET: new FPHA argument to specify the FP type for FP homogeneous arrays (MOD-13577)
#14892 ZUNION, ZINTER, ZUNIONSTORE, ZINTERSTORE: new COUNT aggregator
RedisTimeSeries/RedisTimeSeries#1916 TS.RANGE, TS.REVRANGE, TS.MRANGE, TS.MREVRANGE: multiple aggregators in a single command (MOD-9162)

Bug fixes (compared to 8.6.2)

#15037 XINFO STREAM: wrong value in the per-slot memory tracking
#12000 Incorrect shrinking of querybuf when client is reading a big argv
#15021 HEXPIRE: overflow on fields count
#14963 XREADGROUP: consumer replication inconsistency
#15011 Double-free in rdbLoadObject
#14667, #14886 Potential TCP stalls/deadlocks
#14942 Fix COMMAND GETKEYS for PFMERGE with no source keys
#14888 Hardens safety check in lpSafeToAdd
#14748 Ensure sensitive user data is not exposed in logs when hide_user_data_from_log is enabled
#14877 INFO KEYSIZES and INFO ALLOCSIZES fixes
#14878 listpack memory leak in zipmap-to-hash conversion on error path
#14955 Streams: IDMP-related bug
#14974, #14932, #14866 Memory leaks
#14790 Missing initialization
#14789 DB hash tables not expanding during RDB load on standalone-mode
#14785 Add HOTKEYS HELP subcommand (Each command having subcommands needs a HELP subcommand)
#14784 RESTORE and SET: expiredkeys counter updates incorrectly on keys with past expiration time
#14779 Accurate memory accounting for RedisModuleDict (instead of estimation)
#14774 Missing cleanup code in getKeysFreeResult() on cross-slot error path
#14771 Potential unsigned integer underflow in used_memory_dataset calculation
#14780 Fixed name of HOTKEYS results field sampled-command-selected-slots-us to sampled-commands-selected-slots-us
#14756 HOTKEYS does not track each command in a MULTI/EXEC block
#14749 Fixed HOTKEYS GET RESP3 reply fixed to map instead of flat array
RedisJSON/RedisJSON#1520 Numeric operations on homogeneous arrays: promote to next type if results overflow (MOD-14427)
RedisJSON/RedisJSON#1519 JSON.NUMINCRBY, JSON.NUMMULTBY don’t error on numeric overflow (MOD-14191)
RedisJSON/RedisJSON#1487 Depth limit (128) was not fully enforced (MOD-4107)
RedisTimeSeries/RedisTimeSeries#1910 TS.INCRBY, TS.DECRBY create key before validating args (MOD-8167)
RedisTimeSeries/RedisTimeSeries#1908 Potential crash on TS.RANGE with aggregation and EMPTY
RedisTimeSeries/RedisTimeSeries#1896 Potential memory leak (MOD-13438)
RedisTimeSeries/RedisTimeSeries#1913 ACL rules are not fully enforced for multi-key commands on a cluster setup (MOD-14124)

Performance and resource utilization improvements (compared to 8.6.2)

#15003 Reduce overhead in command propagation
#14979 Dismiss dict bucket arrays in fork child to reduce CoW
#14661 Replace fast_float C++ library with pure C implementation
#14928 Disable memory tracking in child processes
#14885 Optimize rax (radix tree) insert and lookup for sequential key patterns
#14335 Handle primary/replica clients in I/O threads
#14754 Optimize prefetching commands
#14770 Optimize BITOP operations with AVX512
#14862 Streams: Filter expired IDMP entries during RDB save and load
#14750 SFLUSH can now flush slots partially
#14887 SFLUSH skips slot trimming when the requested slot ranges exactly match the node’s local slot coverage
#14851 Skip RDB checksum computation/validation during diskless full synchronization to reduce CPU overhead
#14783 Pause dict auto-resize during multi-field deletion
RedisTimeSeries/RedisTimeSeries#1884 TS.RANGE, TS.REVRANGE, TS.MRANGE, TS.MREVRANGE: improve performance on a cluster setup (RED-184104)
RedisTimeSeries/RedisTimeSeries#1866 Register to type_changed KSN instead of set (MOD-12919)

Modules API

#14445 Allow modules to associate metadata with keys
- RedisModule_CreateKeyMetaClass - define a new key-metadata class
- RedisModule_ReleaseKeyMetaClass - release a key-metadata class
- RedisModule_SetModuleMetadata - attach or update metadata to a key
- RedisModule_GetKeyMeta - get key metadata

Metrics

#14896 INFO STATS - global stats for slowlog metrics:
- slowlog_commands_count - commands written to slowlog
- slowlog_commands_time_ms_sum - sum of execution times of commands from the slowlog
- slowlog_commands_time_ms_max - maximum execution time of a command from the slowlog
#14896 INFO COMMANDSTATS - per-command stats for slowlog metrics:
- slowlog_count - number of times the command was written in the slowlog
- slowlog_time_ms_sum - sum of execution time of the command (only from the slowlog)
- slowlog_time_ms_max - maximum execution time of the command (only from the slowlog)
#14841 INFO STATS (global, all clients aggregated):
- total_client_processing_events: attempts to process client input buffers; does not guarantee any command was actually parsed
- eventloop_cycles_with_clients_processing: event loop cycles where client input buffers were processed
- commands_per_parse_batch_sum: cumulative number of commands parsed across all parsing batches for all clients
- commands_per_parse_batch_cnt: number of parsing batches across all clients. A batch is counted each time at least one command is parsed from a client's query buffer
- commands_per_parse_batch_avg: average commands parsed per batch (sum/cnt). Approximates pipelining depth
#14841 CLIENT INFO and CLIENT LIST (per-client):
- read-events: number of read events for this client
- parse-batch-cmd-sum: cumulative number of commands parsed across all parsing batches for this client
- parse-batch-cnt: total number of parsing batches for this client. Divide parse-batch-cmd-sum by this value to get the client’s average commands per batch