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Redis Info command

Redis server

Redis Info command in an easy to understand and read format, the return value of various information and statistics about the Redis server.

Given by the optional parameter section, allows the command to return only some of the information:

  • server: General Redis server information, contains the following fields:

    • redis_version: Redis server version
    • redis_git_sha1: Git SHA1
    • redis_git_dirty: Git dirty flag
    • os: Redis server host operating system
    • arch_bits: architecture (32 or 64)
    • multiplexing_api: event handling mechanism used Redis
    • gcc_version: GCC version used to compile Redis
    • process_id: server process PID
    • run_id: Redis server random identifier (for Sentinel and clusters)
    • tcp_port: TCP / IP listening port
    • uptime_in_seconds: Since Redis server is started, the number of seconds elapsed
    • uptime_in_days: Since Redis server is started, the number of days elapsed
    • lru_clock: in minutes growing self-clock for LRU management
  • clients: the connected client information, contains the following fields:

    • connected_clients: the number of connected clients (not including the clients connect via the slave server)
    • client_longest_output_list: current client connections among the longest in the output list
    • client_longest_input_buf: current client connection, the greatest input buffer
    • blocked_clients: Waiting for blocking command (BLPOP, BRPOP, BRPOPLPUSH) the number of clients
  • memory: memory information, contains the following fields:

    • used_memory: Redis by the amount of memory allocator, in bytes (byte) units
    • used_memory_human: human-readable format to return the amount of memory allocated Redis
    • used_memory_rss: From the operating system point of view, the return Redis allocated amount of memory (commonly known as resident set size). This value is consistent with the output and top, ps and other commands.
    • used_memory_peak: Redis peak consumption of memory (in bytes)
    • used_memory_peak_human: human-readable format to return Redis peak memory consumption
    • used_memory_lua: Lua engine used by the memory size (in bytes)
    • Used_memory_rss and used_memory ratio between: mem_fragmentation_ratio
    • mem_allocator: specified at compile time, Redis used memory allocator. It can be libc, jemalloc or tcmalloc.

    In the ideal case, the value of used_memory_rss should be only slightly higher than used_memory little.

    When rss> used, and both the value of the difference between the larger, indicates the presence of (internal or external) memory fragmentation.

    The ratio of memory fragmentation can be seen by the value mem_fragmentation_ratio.

    When used> rss, Redis represents part of the operating system memory is swapped out to swap space, in this case, the operation may cause significant delays.

    Redis is released when the memory allocator may, or may not, be returned to the operating system memory.

    If Redis release the memory, but the memory will not be returned to the operating system, then the value of the operating system and used_memory may display Redis memory footprint is not consistent.

    Value View used_memory_peak can verify whether this occurred.

  • persistence: RDB and AOF infos

  • stats: General Statistics

  • replication: master / slave replication information

  • cpu: CPU computational statistics

  • commandstats: Redis command statistics

  • cluster: Redis cluster information

  • keyspace: database-related statistics

grammar

redis Info command basic syntax is as follows:

redis 127.0.0.1:6379> INFO [section] 

Available versions

> = 1.0.0

return value

String text line collection.

Examples

redis 127.0.0.1:6379> INFO
# Server
redis_version:2.5.9
redis_git_sha1:473f3090
redis_git_dirty:0
os:Linux 3.3.7-1-ARCH i686
arch_bits:32
multiplexing_api:epoll
gcc_version:4.7.0
process_id:8104
run_id:bc9e20c6f0aac67d0d396ab950940ae4d1479ad1
tcp_port:6379
uptime_in_seconds:7
uptime_in_days:0
lru_clock:1680564

# Clients
connected_clients:1
client_longest_output_list:0
client_biggest_input_buf:0
blocked_clients:0

# Memory
used_memory:439304
used_memory_human:429.01K
used_memory_rss:13897728
used_memory_peak:401776
used_memory_peak_human:392.36K
used_memory_lua:20480
mem_fragmentation_ratio:31.64
mem_allocator:jemalloc-3.0.0

# Persistence
loading:0
rdb_changes_since_last_save:0
rdb_bgsave_in_progress:0
rdb_last_save_time:1338011402
rdb_last_bgsave_status:ok
rdb_last_bgsave_time_sec:-1
rdb_current_bgsave_time_sec:-1
aof_enabled:0
aof_rewrite_in_progress:0
aof_rewrite_scheduled:0
aof_last_rewrite_time_sec:-1
aof_current_rewrite_time_sec:-1

# Stats
total_connections_received:1
total_commands_processed:0
instantaneous_ops_per_sec:0
rejected_connections:0
expired_keys:0
evicted_keys:0
keyspace_hits:0
keyspace_misses:0
pubsub_channels:0
pubsub_patterns:0
latest_fork_usec:0

# Replication
role:master
connected_slaves:0

# CPU
used_cpu_sys:0.03
used_cpu_user:0.01
used_cpu_sys_children:0.00
used_cpu_user_children:0.00

# Keyspace

Redis server