3 memcached_behavior_get memcached_behavior_set
7 C Client Library for memcached (libmemcached, -lmemcached)
11 #include <memcached.h>
14 memcached_behavior_get (memcached_st *ptr,
15 memcached_behavior flag);
18 memcached_behavior_set (memcached_st *ptr,
19 memcached_behavior flag,
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>).
30 memcached_behavior_get() takes a behavior flag and returns whether or not
31 that behavior is currently enabled in the client.
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.
40 =item MEMCACHED_BEHAVIOR_REPLICAS
42 By default libmemcached(3) stores data in just one node of the cluster. Setting this value
43 to a number will cause that number of copies to be kept. The value must be greater then
44 zero, and must be at most the same value as the number of hosts in the cluster.
46 =item MEMCACHED_BEHAVIOR_NO_BLOCK
48 Causes libmemcached(3) to use asychronous IO. This is the fastest transport
49 available for storage functions. For read operations it is currently
50 similar in performance to the non-blocking method (this is being
53 =item MEMCACHED_BEHAVIOR_TCP_NODELAY
55 Turns on the no-delay feature for connecting sockets (may be faster in some
58 =item MEMCACHED_BEHAVIOR_HASH
60 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.
62 =item MEMCACHED_BEHAVIOR_DISTRIBUTION
64 Using this you can enable different means of distributing values to servers.
65 The default method is MEMCACHED_DISTRIBUTION_MODULA. You can enable
66 consistent hashing by setting MEMCACHED_DISTRIBUTION_CONSISTENT.
67 Consistent hashing delivers better distribution and allows servers to be
68 added to the cluster with minimal cache losses.
70 =item MEMCACHED_BEHAVIOR_CACHE_LOOKUPS
72 Memcached can cache named lookups so that DNS lookups are made only once.
74 =item MEMCACHED_BEHAVIOR_SUPPORT_CAS
76 Support CAS operations (this is not enabled by default at this point in the server since it imposes a slight performance penalty).
78 =item MEMCACHED_BEHAVIOR_POLL_TIMEOUT
80 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.
82 =item MEMCACHED_BEHAVIOR_USER_DATA
84 This allows you to store a pointer to a specifc piece of data. This can be
85 retrieved from inside of memcached_fetch_execute(). Cloning a memcached_st
87 will copy the pointer to the clone. This was deprecated in 0.14 in favor
88 of memcached_callback_set(3). This will be removed in 0.15.
90 =item MEMCACHED_BEHAVIOR_BUFFER_REQUESTS
92 Enabling buffered IO causes commands to "buffer" instead of being sent. Any
93 action that gets data causes this buffer to be be sent to the remote
94 connection. Quiting the connection or closing down the connection will also
95 cause the buffered data to be pushed to the remote connection.
97 =item MEMCACHED_BEHAVIOR_VERIFY_KEY
99 Enabling this will cause libmemcached(3) to test all keys to verify that they
102 =item MEMCACHED_BEHAVIOR_SORT_HOSTS
104 Enabling this will cause hosts that are added to be placed in the host list in
105 sorted order. This will defeat consisten hashing.
107 =item MEMCACHED_BEHAVIOR_CONNECT_TIMEOUT
109 In non-blocking mode this changes the value of the timeout during socket
116 memcached_behavior_get() returns either the current value of the get, or 0
117 or 1 on simple flag behaviors (1 being enabled). memcached_behavior_set()
118 returns whether or not the behavior was enabled.
122 memcached_behavior_set() in version .17 was changed from taking a pointer
123 to data value, to taking a uin64_t.
127 To find out more information please check:
128 L<http://tangent.org/552/libmemcached.html>
132 Brian Aker, E<lt>brian@tangent.orgE<gt>
136 memcached(1) libmemcached(3) memcached_strerror(3)