Memcached common commands

1. start Memcache's common parameter-p & lt; num & gt; set the port number (default value: 11211)-U & lt; num & gt; UDP listening port (default value: -l & lt; ip_addr & gt; binding address (default: all allow, regardless of the intranet or Internet or local IP address, there is a security risk, if...

 

1. start common Memcache parameters

-P Set the port number (default value: 11211)

-U UDP listening port (default: 11211, disabled at 0)

-L Binding address (default: all allow, regardless of the intranet and internet or the local machine to change the IP address, there is a security risk, if set to 127.0.0.1, only local access is allowed)

-D independent process running

-U Bind to use the specified process for running

-M Maximum memory usage allowed, in MB (default: 64 MB)

-P Write PID to file In this way, the following process can be terminated quickly and must be used together with-d.

For example:

In linux:./usr/local/bin/memcached-d-u jb-mc-l 192.168.1.197-m 2048-p 12121

In the window: d: \ App_Serv \ memcached \ memcached.exe-d RunService-l 127.0.0.1-p 11211-m 500

Register as a service in windows and run:

SC .exe create jb-Memcached binpath = "d: \ App_Serv \ memcached \ memcached.exe-d RunService-p 11211-m 500" start = auto

Net start jb-Memcached

 

2. connection: telnet 127.0.0.1 11211

3. you will use five basic memcached commands to perform the simplest operations. These commands and operations include:

 

Set: used to add a new key-value pair to the cache. If the key already exists, the previous value is replaced.

Add: the add command adds a key-value pair to the cache only when the key does not exist in the cache. If a key already exists in the cache, the previous values remain the same and you will get the response NOT_STORED.

Replace: the replace command replaces the cached key only when the key already exists. If no key exists in the cache, you will receive a NOT_STORED response from the memcached server.

Get: used to retrieve values related to previously added key-value pairs.

Delete: delete any existing values in memcached. You will use a key to call delete. if the key exists in the cache, the value is deleted. If not, a NOT_FOUND message is returned.

Gets: similar to basic get commands. The difference between the two commands is that gets returns a little more information: The 64-bit integer value is very similar to the "version" identifier of the name/value pair.

The first three commands are standard modification commands used to operate key-value pairs stored in memcached. They are both very easy to use and all use the syntax shown in listing 5:

 

Command

 

Table 1. modify command parameters of memcached

 

Parameter usage

Key is used to find the cache value.

Flags can include an integer parameter of a key-value pair. the client uses it to store additional information about the key-value pair.

Expiration time the length of time when the key-value pair is saved in the cache (in seconds, 0 indicates permanent)

Bytes stored in the cache

Example of the value stored by value (always in the second row:

Set useID 0 0 5

 

1234

 

 

 

4. cache management commands

 

The last two memcached commands are used to monitor and clear memcached instances. They are stats and flush_all commands.

 

Stats: dump the current statistics of the connected memcached instance.

Flush_all: used to clear all name/value pairs in the cache. If you need to reset the cache to a clean state, flush_all can be of great use.

Run the following command to view the memcached status:

 

STAT pid 22459 process ID

STAT uptime 1027046 server running seconds

STAT time 1273043062 server current unix timestamp

STAT version 1.4.4 server version

STAT pointer_size 64 OS font size (this server is 64-bit)

STAT rusage_user 0.040000 cumulative process user time

STAT rusage_system 0.260000 cumulative system time of processes

STAT curr_connections 10 number of currently opened connections

STAT total_connections 82 total number of connections opened

STAT connection_structures 13 Number of connection structures allocated by the server

STAT cmd_get 54 total number of get commands executed

STAT cmd_set 34 total number of set commands executed

STAT cmd_flush 3 points to the total number of flush_all commands

STAT get_hits 9 get hits

STAT get_misses 45 get Miss times

STAT delete_misses 5 delete Miss times

STAT delete_hits 1 delete hits

STAT incr_misses 0 incr Miss count

STAT incr_hits 0 incr hits

STAT decr_misses 0 decr Miss count

STAT decr_hits 0 decr hits

STAT cas_misses 0 cas Miss count

STAT cas_hits 0 cas hits

STAT cas_badval 0 used for wiping

STAT auth_cmds 0

STAT auth_errors 0

STAT bytes_read 15785 total number of bytes read

STAT bytes_written 15222 total number of written bytes

STAT limit_maxbytes 1048576 memory allocated (bytes)

STAT accepting_conns 1 currently accepted connections

STAT listen_disabled_num 0

STAT threads 4 threads

STAT conn_yields 0

STAT bytes 0 stores item bytes

STAT curr_items 0 item count

STAT total_items 34 total items

STAT evictions 0 indicates the total number of items deleted from the retrieved space.

 

From iloveyin