Python uses memcached

Reprinted from Http://oursimplehouse.blog.sohu.com/63588732.html

Install memcached:
1. Download memcached-1.2.2.tar.gz
2. Tar xvzf memcached-1.2.2.tar.gz
3./configure;make;make Install

To install the Python API components:
1. Download python-memcached-1.39.tar.gz
2. Tar xvzf python-memcached-1.39.tar.gz
3. Python setup.py Install

Start memcached
Memcached-d-M 64-l 10.1.41.113-p 11211
This memcached is started as a daemon mode (-D), and then the cache space is 64M (-m), listening (-L) Server 10.1.41.113 port 11,212th (-P)
Add-u to specify the user parameter under root
Memcached-u bj1822-d-M 64-l 10.1.41.113-p 11211

Memcached-h
Memcached 1.2.2
-P <num> TCP port number to listen on (default:11211)
-U <num> UDP port number to listen on (default:0, off)
-S <file> UNIX socket path to listen on (disables network support)
-L <ip_addr> interface to listen in, default is Indrr_any
-D Run as a daemon
-R Maximize Core file limit
-U <username> assume identity of <username> (only if run as root)
-M <num> max memory to use for items in megabytes, default is ~ MB
-M return error on memory exhausted (rather than removing items)
-C <num> Max simultaneous connections, default is 1024
-K Lock down all paged memory
-V Verbose (print errors/warnings while in event loop)
-VV very verbose (also print client commands/reponses)
-H Print this help and exit
-I print memcached and libevent license
-B Run a managed instanced (mnemonic:buckets)
-P <file> Save PID in <file>, only used with-d option
-F <factor> chunk size growth factor, default 1.25
-N <bytes> minimum space allocated for key+value+flags, default 48

To write a Python program:
Import Memcache, Time
MC = Memcache. Client ([' 10.1.41.113:11211 '], debug=0)
Connect to the 10.1.41.113 11211 port, which is the MEMCACHD-initiated port.

Mc.set ("Some_key", "some value")
Set key and value, the third parameter defaults to 0, which means the data never times out.
If this is set:
Mc.set ("Some_key", "some value", 1)
Indicates timeout after one second
Two seconds to print value.
Time.sleep (2)
Value = Mc.get ("Some_key")
Print value
The result is none.

Delete
Mc.set ("Another_key", 3)                                                                               mc.delete ("Another_key")                                                                                                                 
Self-increment and self-reduction
Mc.set ("Key", "1")                                                                                     mc.incr ("key")                                                                                           MC.DECR ("key")           

About LRU
LRU is a buffer over the storage limit when the deletion of the trailing tail is the longest time no one to access the element, the parameter is-M. However, setting the-m and expiration time will present the risk of deleting the elements that are not invalidated. So someone on the internet changed the code to increase the judgment on Expiration Time:

Returns the code for the time-out:
if (Exptime > Realtime_maxdelta)
Return (rel_time_t) (exptime-stats.started);
else {
Return (rel_time_t) (Exptime + current_time);
}
There are two memcached of the Expiration Time format, which is the number of seconds to expire from January 1, 1970 when the number of seconds is greater than 60*60*24*30, which is 30 days, otherwise it is a valid number of seconds.

Delete the cache's code:
for (search = Tails[id]; tries>0 && search; tries--, Search=search->prev) {
if (search->refcount==0) {
Item_unlink (search);
Break
}
}
Additional conditions:
Search->exptime && search->exptime <= current_time
This will ensure that the deleted elements are all out of date.

Python uses memcached