Common Redis Commands include INFO, MONITOR, and SLOWLOG.

Author: zhanhailiang Date: 2014-12-021.INFOinfo command returns server-related information, including: server: GeneralinformationabouttheRedisserverclients: Clientconnectionssectionmemory: Memoryconsumptionrelatedinformationpersistence: RDBandAOFr

Author: zhanhailiang Date: 2014-12-02 1. the INFO info command returns server information, including: server: General information about the Redis server clients: Client connections section memory: Memory consumption related information persistence: RDB and AOF r

Author: zhanhailiang Date: 2014-12-02

1. INFO

The info command returns information about the server, including:

• Server: General information about the Redis server
• Clients: Client connections section
• Memory: Memory consumption related information
• Persistence: RDB and AOF related information
• Stats: General statistics
• Replication: Master/slave replication information
• Cpu: CPU consumption statistics
• Commandstats: Redis command statistics
• Cluster: Redis Cluster section
• Keyspace: Database related statistics

  It supports custom return lists:

  [root@~]# redis-cli info[root@~]# redis-cli info default[root@~]# redis-cli info all

  See http://www.redis.cn/commands/info.html for details

  2. MONITOR

  MONITOR is a debugging command that returns every command processed by the server. It helps us understand what operations have taken place on the database. There are three methods:

  [root@~]# redis-cli monitorOK1417532512.619715 [0 127.0.0.1:55043] "REPLCONF" "ACK" "6623624"[root@~]# telnet 127.0.0.1 6379Trying 127.0.0.1...Connected to 127.0.0.1.Escape character is '^]'.monitor+OK+1417532567.733458 [0 127.0.0.1:55043] "REPLCONF" "ACK" "6623708"+1417532568.735936 [0 127.0.0.1:55043] "REPLCONF" "ACK" "6623708"quit+OKConnection closed by foreign host.[root@~]# redis-cli 127.0.0.1:6379> monitorOK1417532590.785487 [0 127.0.0.1:55043] "REPLCONF" "ACK" "6623736"

  Because the MONITOR command returns all the commands processed by the server, it consumes some performance. The test results using the official stress testing tool are as follows:

  Benchmark's test results without running the MONITOR command:

  [root@~/software/redis-2.8.17]# src/redis-benchmark -c 10 -n 100000 -qPING_INLINE: 51020.41 requests per secondPING_BULK: 50607.29 requests per secondSET: 37257.82 requests per secondGET: 49800.80 requests per secondINCR: 38699.69 requests per secondLPUSH: 38910.51 requests per secondLPOP: 39277.30 requests per secondSADD: 54614.96 requests per secondSPOP: 51948.05 requests per secondLPUSH (needed to benchmark LRANGE): 38819.88 requests per secondLRANGE_100 (first 100 elements): 20112.63 requests per secondLRANGE_300 (first 300 elements): 9025.27 requests per secondLRANGE_500 (first 450 elements): 6836.67 requests per secondLRANGE_600 (first 600 elements): 5406.28 requests per secondMSET (10 keys): 19394.88 requests per second

  When running the MONITOR command, benchmark Test Result: (redis-cli monitor>/dev/null ):

  [root@~/software/redis-2.8.17]# src/redis-benchmark -c 10 -n 100000 -qPING_INLINE: 42211.91 requests per secondPING_BULK: 42936.88 requests per secondSET: 26143.79 requests per secondGET: 33990.48 requests per secondINCR: 26553.37 requests per secondLPUSH: 27337.34 requests per secondLPOP: 27225.70 requests per secondSADD: 30459.95 requests per secondSPOP: 39494.47 requests per secondLPUSH (needed to benchmark LRANGE): 26315.79 requests per secondLRANGE_100 (first 100 elements): 22055.58 requests per secondLRANGE_300 (first 300 elements): 8104.38 requests per secondLRANGE_500 (first 450 elements): 6371.05 requests per secondLRANGE_600 (first 600 elements): 5031.95 requests per secondMSET (10 keys): 14861.05 requests per second

  We can see that all the indicators have declined.

  See http://www.redis.cn/commands/monitor.html for details

  3. SLOWLOG

  You can use SLOWLOG to read slow query logs.

  You can use slowlog len to obtain the length of the current slow log.

  [root@~/software/redis-2.8.17]# redis-cli 127.0.0.1:6379> slowlog len(integer) 28

  You can use slowlog get to obtain all slow logs.

  127.0.0.1:6379> slowlog get  1) 1) (integer) 27    2) (integer) 1417531320    3) (integer) 24623    4) 1) "info"

  The indicators are as follows:

  • A unique progressive identifier for every slow log entry.
  • The unix timestamp at which the logged command was processed.
  • The amount of time needed for its execution, in microseconds (Note: microseconds is translated into microseconds instead of milliseconds ).
  • The array composing the arguments of the command.

    You can use slowlog get n to obtain the last N slow logs.

    127.0.0.1:6379> slowlog get 21) 1) (integer) 27   2) (integer) 1417531320   3) (integer) 24623   4) 1) "info"2) 1) (integer) 26   2) (integer) 1417528379   3) (integer) 21363   4) 1) "get"      2) "user:score"

    Use the slowlog reset command to RESET slow logs. Once executed, all previous slow logs will be lost.

    127.0.0.1:6379> slowlog reset