memcached command-line operation detailed

Connect to the memcached command line: Telnet 127.0.0.1 11211

1.set/add/replace:

Format:<command> <key> <flags> <exptime> <bytes> (click Enter)

<data>

A) <command> can be "set", "Add", "replace".
"Set" means that the data is stored in accordance with the corresponding <key>, there is no time to increase, some overwrite.
"Add" means that the data is added according to the appropriate <key>, but the operation fails if the <key> already exists.
"Replace" means that the data is replaced by the appropriate <key>, but the operation fails if the <key> does not exist

b) <key> the client needs to save the data key.

c) <flags> is a 16-bit unsigned integer (expressed in decimal notation).
The flag is stored along with the data that needs to be stored and is returned when the client get data.
Customers can use this flag for special purposes and this flag is opaque to the server.

D) The time of <exptime> expires.
A 0 indicates that the stored data is never obsolete (but can be replaced by the server algorithm: LRU, etc.).
If it is not 0 (Unix time or the number of seconds in the distance), when it expires, the server can guarantee that the user will not get the data (server time is the standard).

e) <bytes> the number of bytes that need to be stored,,<bytes> can be 0 when the user wants to store empty data

f) <data block> stored data, the length is the same as the specified bytes, greater than and less than will be an error.

Set 0 0 3 leestored Set 0 0 3 leeeclient_error Bad Data chunkerror

2.get: you can get the value of multiple keys

Get03Lee

3. Deletion: Delete key time

// Delete name now Ten  // Delete after 10s, test failed

4. Check the server Status:

Stats

PID: Process iduptime: Total run time, seconds time: Current times version: Revision number ... Curr_items: number of keyvalue in the current cache total_items: KeyValue number bytes: The amount of memory used by all caches curr_connections the current number of connections .... cmd_get: Total fetches Cmd_set: Total number of writes Get_hits: Total hits Miss_hits: Get the number of  failures ... Bytes_read : Total bytes of traffic read Bytes_written: Total bytes of write traffic
Limit_maxbytes: Maximum allowable amount of memory, bytes

Stats Reset
Clear statistics

Stats malloc//test Failed
Display memory allocation data

Stats Cachedump slab_id Limit_num
Displays a list of the first limit_num keys in a slab

Stats Slabs
Displays information about each slab, including the size, number, usage, etc. of the chunk

Stats items
Displays the number of item in each slab and the age of the oldest item (the number of seconds the last access distance is now)

Stats detail [On|off|dump]
Set or display detailed operation Records

parameter is on to open detailed operation record
parameter is off, close verbose operation record
The parameter is dump, showing the detailed operation record (number of times each key value get, set, hit, Del)

Flush_all

Clear all Key values
Note: Flush does not delete items, except that all items are marked as expired, so Memcache still occupies all of the memory.

Command Description Example:

Get	Reads a value	Get MyKey
Set	Set a key unconditionally	Set MyKey 0 60 5
Add	ADD a new key	Add Newkey 0 60 5
Replace	Overwrite existing Key	Replace key 0 60 5
Append	Append data to existing key	Append key 0 60 15
Prepend	Prepend data to existing key	Prepend Key 0 60 15
incr	Increments numerical key value by given number	INCR MyKey 2
Decr	Decrements numerical key value by given number	DECR MyKey 5
Delete	Deletes an existing key	Delete MyKey
Flush_all	Invalidate specific items immediately	Flush_all
Invalidate all items in n seconds	Flush_all 900
Stats	Prints General Statistics	Stats
Prints Memory Statistics	Stats Slabs
Prints Memory Statistics	Stats malloc
Print Higher level allocation statistics	Stats items
	Stats Detail
	Stats sizes
Resets statistics	Stats Reset
Version	Prints Server version.	Version
Verbosity	Increases log level	Verbosity
Quit	Terminate Telnet session	Quit

memcached command-line operation detailed