LATENCY HISTOGRAM
Syntax
LATENCY HISTOGRAM [command [command ...]]
- Available since:
- 7.0.0
- Time complexity:
- O(N) where N is the number of commands with latency information being retrieved.
- ACL categories:
-
@admin
,@slow
,@dangerous
,
LATENCY HISTOGRAM
returns a cumulative distribution of commands' latencies in histogram format.
By default, all available latency histograms are returned. You can filter the reply by providing specific command names.
Each histogram consists of the following fields:
- Command name
- The total calls for that command
- A map of time buckets:
- Each bucket represents a latency range
- Each bucket covers twice the previous bucket's range
- Empty buckets are excluded from the reply
- The tracked latencies are between 1 nanosecond and roughly 1 second
- Everything above 1 second is considered +Inf
- At max, there will be log2(1,000,000,000) = 30 buckets
This command requires the extended latency monitoring feature to be enabled, which is the default.
If you need to enable it, call CONFIG SET latency-tracking yes
.
To delete the latency histograms' data use the CONFIG RESETSTAT
command.
Examples
127.0.0.1:6379> LATENCY HISTOGRAM set
1# "set" =>
1# "calls" => (integer) 100000
2# "histogram_usec" =>
1# (integer) 1 => (integer) 99583
2# (integer) 2 => (integer) 99852
3# (integer) 4 => (integer) 99914
4# (integer) 8 => (integer) 99940
5# (integer) 16 => (integer) 99968
6# (integer) 33 => (integer) 100000