Redis Server Operations

"Redis Server Operations "

1. Time

Returns the current server time.

2,dbsize

Returns the number of keys for the current database.

3,Lastsave

Returns the time that the most recent Redis successfully saved data to disk, expressed in the UNIX timestamp format.

4,BGSAVE

Asynchronously (asynchronously) saves data from the current database to disk in the background.

The BGSAVE command returns immediately after execution, OK then Redis fork out a new subprocess, the original Redis process (the parent process) continues to process the client request, and the child process is responsible for saving the data to disk and then exiting.

The client can view the relevant information through the Lastsave command and determine whether the BGSAVE command is successful.

5,flushdb

Clears all keys in the current database.

This command never fails.

6,Flushall

Clears the data for the entire Redis server (all keys for all databases are deleted).

This command never fails.

7.slowlog subcommand [argument]

What is Slowlog

Slow log is a log system used by Redis to record query execution times.

Query execution time refers to not including IO operations such as client response (talking), sending replies, and simply the time spent executing a query command.

In addition, the slow log is stored in memory and reads and writes very quickly, so you can use it with confidence, without worrying about the speed of Redis due to opening slow log.

Set Slowlog

The behavior of Slow log is specified by two configuration parameters (config parameter) and can be dynamically modified by overwriting redis.conf files or by using CONFIG GET and CONFIG SET commands.

The first option is slowlog-log-slower-than that it determines how many microseconds (microsecond,1 seconds = 1,000,000 microseconds) of execution time are recorded for queries.

For example, executing the following command will let slow log log all queries that have a query time greater than or equal to 100 microseconds:

CONFIG SET slowlog-log-slower-than 100

The following command logs all queries that have a query time greater than 1000 microseconds:

CONFIG SET slowlog-log-slower-than 1000

Another option is slowlog-max-len that it determines how many logs slow log can hold, slow log itself is a FIFO queue, and when the queue size is exceeded, the oldest slowlog-max-len log is deleted, and the latest log is added to the slow log, and so on.

The following command allows slow log to save up to 1000 logs:

CONFIG SET slowlog-max-len 1000

Redis Server Operations