ef8206686f172a8be54fa0c32ef71bd8a5916dec
[m6w6/libmemcached] / docs / memcached_behavior.pod
1 =head1 NAME
2
3 memcached_behavior_get memcached_behavior_set
4
5 =head1 LIBRARY
6
7 C Client Library for memcached (libmemcached, -lmemcached)
8
9 =head1 SYNOPSIS
10
11 #include <memcached.h>
12
13 unsigned long long
14 memcached_behavior_get (memcached_st *ptr,
15 memcached_behavior flag);
16
17 memcached_return
18 memcached_behavior_set (memcached_st *ptr,
19 memcached_behavior flag,
20 void *data);
21
22 =head1 DESCRIPTION
23
24 libmemcached(3) behavior can be modified by use memcached_behavior_set().
25 Default behavior is the library strives to be quick and accurate. Some
26 behavior, while being faster, can also result in not entirely accurate
27 behavior (for instance, memcached_set() will always respond with
28 C<MEMCACHED_SUCCESS>).
29
30 memcached_behavior_get() takes a behavior flag and returns whether or not
31 that behavior is currently enabled in the client.
32
33 memcached_behavior_set() changes the value of a particular option of the
34 client. It takes both a flag (listed below) and a value. For simple on or
35 off options you just need to pass in a value of 1. Calls to
36 memcached_behavior_set() will flush and reset all connections.
37
38 =over 4
39
40 =item MEMCACHED_BEHAVIOR_NO_BLOCK
41
42 Causes libmemcached(3) to use asychronous IO. This is the fastest transport
43 available for storage functions. For read operations it is currently
44 similar in performance to the non-blocking method (this is being
45 looked into).
46
47 =item MEMCACHED_BEHAVIOR_TCP_NODELAY
48
49 Turns on the no-delay feature for connecting sockets (may be faster in some
50 environments).
51
52 =item MEMCACHED_BEHAVIOR_HASH
53
54 Makes the default hashing algorithm for keys use MD5. The value can be set to either MEMCACHED_HASH_DEFAULT, MEMCACHED_HASH_MD5, MEMCACHED_HASH_CRC, MEMCACHED_HASH_FNV1_64, MEMCACHED_HASH_FNV1A_64, MEMCACHED_HASH_FNV1_32, MEMCACHED_HASH_FNV1A_32, MEMCACHED_HASH_KETAMA. The behavior for all hashes but MEMCACHED_HASH_DEFAULT is identitical to the Java driver written by Dustin Sallings.
55
56 =item MEMCACHED_BEHAVIOR_DISTRIBUTION
57
58 Using this you can enable different means of distributing values to servers.
59 The default method is MEMCACHED_DISTRIBUTION_MODULA. You can enable
60 consistent hashing by setting MEMCACHED_DISTRIBUTION_CONSISTENT.
61 Consistent hashing delivers better distribution and allows servers to be
62 added to the cluster with minimal cache losses.
63
64 =item MEMCACHED_BEHAVIOR_CACHE_LOOKUPS
65
66 Memcached can cache named lookups so that DNS lookups are made only once.
67
68 =item MEMCACHED_BEHAVIOR_SUPPORT_CAS
69
70 Support CAS operations (this is not enabled by default at this point in the server since it imposes a slight performance penalty).
71
72 =item MEMCACHED_BEHAVIOR_POLL_TIMEOUT
73
74 Modify the timeout value that is used by poll(). The default value is -1. An signed int pointer must be passed to memcached_behavior_set() to change this value. For memcached_behavior_get() a signed int value will be cast and returned as the unsigned long long.
75
76 =item MEMCACHED_BEHAVIOR_USER_DATA
77
78 This allows you to store a pointer to a specifc piece of data. This can be
79 retrieved from inside of memcached_fetch_execute(). Cloning a memcached_st
80 will copy the pointer to the clone. This was deprecated in 0.14 in favor
81 of memcached_callback_set(3). This will be removed in 0.15.
82
83 =item MEMCACHED_BEHAVIOR_BUFFER_REQUESTS
84
85 Enabling buffered IO causes commands to "buffer" instead of being sent. Any
86 action that gets data causes this buffer to be be sent to the remote
87 connection. Quiting the connection or closing down the connection will also
88 cause the buffered data to be pushed to the remote connection.
89
90 =back
91
92 =head1 RETURN
93
94 memcached_behavior_get() returns either the current value of the get, or 0
95 or 1 on simple flag behaviors (1 being enabled). memcached_behavior_set()
96 returns whether or not the behavior was enabled.
97
98 =head1 HOME
99
100 To find out more information please check:
101 L<http://tangent.org/552/libmemcached.html>
102
103 =head1 AUTHOR
104
105 Brian Aker, E<lt>brian@tangent.orgE<gt>
106
107 =head1 SEE ALSO
108
109 memcached(1) libmemcached(3) memcached_strerror(3)
110
111 =cut
112