Probabilistic on Docs

HyperLogLog

Mon, 01 Jan 0001 00:00:00 +0000

HyperLogLog command summary (view reference, 5 commands)

HyperLogLog is a probabilistic data structure that estimates the cardinality of a set, trading perfect accuracy for efficient space utilization. The Redis implementation uses up to 12 KB of memory and provides a standard error rate of 0.81%.

Bloom filter

Mon, 01 Jan 0001 00:00:00 +0000

Bloom filter command summary (view reference, 10 commands)

A Bloom filter is a probabilistic data structure in Redis Open Source that enables you to check if an element is present in a set using a very small memory space of a fixed size.

Cuckoo filter

Mon, 01 Jan 0001 00:00:00 +0000

Cuckoo filter command summary (view reference, 12 commands)

A Cuckoo filter, just like a Bloom filter, is a probabilistic data structure in Redis Open Source that enables you to check if an element is present in a set in a very fast and space efficient way, while also allowing for deletions and showing better performance than Bloom in some scenarios.

t-digest

Mon, 01 Jan 0001 00:00:00 +0000

t-digest command summary (view reference, 14 commands)

The t-digest is a sketch data structure in Redis Open Source for estimating percentiles from a data stream or a large dataset using a compact sketch.

Top-K

Mon, 01 Jan 0001 00:00:00 +0000

Top-K command summary (view reference, 7 commands)

Top K is a probabilistic data structure in Redis Open Source used to estimate the K highest-rank elements from a stream.

Count-min sketch

Mon, 01 Jan 0001 00:00:00 +0000

Count-min sketch command summary (view reference, 6 commands)

Count-Min Sketch is a probabilistic data structure in Redis Open Source that can be used to estimate the frequency of events/elements in a stream of data.

Configuration Parameters

Mon, 01 Jan 0001 00:00:00 +0000

Note:

As of Redis 8 in Redis Open Source (Redis 8), configuration parameters for the probabilistic data structures are now set in the following ways:

At load time via your redis.conf file.
At run time (where applicable) using the CONFIG SET command.

Also, Redis 8 persists probabilistic configuration parameters just like any other configuration parameters (e.g., using the CONFIG REWRITE command).