Provided by: libmemcached-libmemcached-perl_1.001801+dfsg-2build2_amd64 bug

NAME

       memcached_behavior_get, memcached_behavior_set - Manipulate behavior

LIBRARY

       C Client Library for memcached (libmemcached, -lmemcached)

SYNOPSIS

         #include <memcached.h>

         uint64_t
           memcached_behavior_get (memcached_st *ptr,
                                   memcached_behavior flag);

         memcached_return_t
           memcached_behavior_set (memcached_st *ptr,
                                   memcached_behavior flag,
                                   uint64_t data);

DESCRIPTION

       libmemcached(3) behavior can be modified by use memcached_behavior_set().  Default
       behavior is the library strives to be quick and accurate. Some behavior, while being
       faster, can also result in not entirely accurate behavior (for instance, memcached_set()
       will always respond with "MEMCACHED_SUCCESS").

       memcached_behavior_get() takes a behavior flag and returns whether or not that behavior is
       currently enabled in the client.

       memcached_behavior_set() changes the value of a particular option of the client. It takes
       both a flag (listed below) and a value. For simple on or off options you just need to pass
       in a value of 1. Calls to memcached_behavior_set() will flush and reset all connections.

       MEMCACHED_BEHAVIOR_USE_UDP
           Causes libmemcached(3) to use the UDP transport when communicating with a memcached
           server. Not all I/O operations are supported when this behavior is enababled. The
           following operations will return "MEMCACHED_NOT_SUPPORTED" when executed with the
           MEMCACHED_BEHAVIOR_USE_UDP enabled: memcached_version(), memcached_stat(),
           memcached_get(), memcached_get_by_key(), memcached_mget(), memcached_mget_by_key(),
           memcached_fetch(), memcached_fetch_result(), memcached_value_fetch().

           All other operations are supported but are executed in a 'fire-and-forget' mode, in
           which once the client has executed the operation, no attempt will be made to ensure
           the operation has been received and acted on by the server.

           libmemcached(3) does not allow TCP and UDP servers to be shared within the same
           libmemached(3) client 'instance'. An attempt to add a TCP server when this behavior is
           enabled will result in a "MEMCACHED_INVALID_HOST_PROTOCOL", as will attempting to add
           a UDP server when this behavior has not been enabled.

       MEMCACHED_BEHAVIOR_NO_BLOCK
           Causes libmemcached(3) to use asychronous IO. This is the fastest transport available
           for storage functions.

       MEMCACHED_BEHAVIOR_SND_TIMEOUT
           This sets the microsecond behavior of the socket against the SO_SNDTIMEO flag.  In
           cases where you cannot use non-blocking IO this will allow you to still have timeouts
           on the sending of data.

       MEMCACHED_BEHAVIOR_RCV_TIMEOUT
           This sets the microsecond behavior of the socket against the SO_RCVTIMEO flag.  In
           cases where you cannot use non-blocking IO this will allow you to still have timeouts
           on the reading of data.

       MEMCACHED_BEHAVIOR_TCP_NODELAY
           Turns on the no-delay feature for connecting sockets (may be faster in some
           environments).

       MEMCACHED_BEHAVIOR_HASH
           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_JENKINS, MEMCACHED_HASH_HSIEH, and
           MEMCACHED_HASH_MURMUR.  Each hash has it's advantages and it's weaknesses. If you
           don't know or don't care, just go with the default.  Support for MEMCACHED_HASH_HSIEH
           is a compile time option that is disabled by default. To enable support for this
           hashing algorithm, configure and build libmemcached with the --enable-hash_hsieh.

       MEMCACHED_BEHAVIOR_DISTRIBUTION
           Using this you can enable different means of distributing values to servers.  The
           default method is MEMCACHED_DISTRIBUTION_MODULA. You can enable consistent hashing by
           setting MEMCACHED_DISTRIBUTION_CONSISTENT.  Consistent hashing delivers better
           distribution and allows servers to be added to the cluster with minimal cache losses.
           Currently MEMCACHED_DISTRIBUTION_CONSISTENT is an alias for the value
           MEMCACHED_DISTRIBUTION_CONSISTENT_KETAMA.

       MEMCACHED_BEHAVIOR_CACHE_LOOKUPS
           Memcached can cache named lookups so that DNS lookups are made only once.

       MEMCACHED_BEHAVIOR_SUPPORT_CAS
           Support CAS operations (this is not enabled by default at this point in the server
           since it imposes a slight performance penalty).

       MEMCACHED_BEHAVIOR_KETAMA
           Sets the default distribution to MEMCACHED_DISTRIBUTION_CONSISTENT_KETAMA and the hash
           to MEMCACHED_HASH_MD5.

       MEMCACHED_BEHAVIOR_KETAMA_WEIGHTED
           Sets the default distribution to MEMCACHED_DISTRIBUTION_CONSISTENT_KETAMA with the
           weighted support.  and the hash to MEMCACHED_HASH_MD5.

       MEMCACHED_BEHAVIOR_KETAMA_HASH
           Sets the hashing algorithm for host mapping on continuum. 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, and
           MEMCACHED_HASH_FNV1A_32.

       MEMCACHED_BEHAVIOR_KETAMA_COMPAT
           Sets the compatibility mode. The value can be set to either
           MEMCACHED_KETAMA_COMPAT_LIBMEMCACHED (this is the default) or
           MEMCACHED_KETAMA_COMPAT_SPY to be compatible with the SPY Memcached client for Java.

       MEMCACHED_BEHAVIOR_POLL_TIMEOUT
           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.

       MEMCACHED_BEHAVIOR_USER_DATA
           This allows you to store a pointer to a specifc piece of data. This can be retrieved
           from inside of memcached_fetch_execute(). Cloning a memcached_st

           will copy the pointer to the clone. This was deprecated in 0.14 in favor of
           memcached_callback_set(3). This will be removed in 0.15.

       MEMCACHED_BEHAVIOR_BUFFER_REQUESTS
           Enabling buffered IO causes commands to "buffer" instead of being sent. Any action
           that gets data causes this buffer to be be sent to the remote connection. Quiting the
           connection or closing down the connection will also cause the buffered data to be
           pushed to the remote connection.

       MEMCACHED_BEHAVIOR_VERIFY_KEY
           Enabling this will cause libmemcached(3) to test all keys to verify that they are
           valid keys.

       MEMCACHED_BEHAVIOR_SORT_HOSTS
           Enabling this will cause hosts that are added to be placed in the host list in sorted
           order. This will defeat consisten hashing.

       MEMCACHED_BEHAVIOR_CONNECT_TIMEOUT
           In non-blocking mode this changes the value of the timeout during socket connection.

       MEMCACHED_BEHAVIOR_BINARY_PROTOCOL
           Enable the use of the binary protocol. Please note that you cannot toggle this flag on
           an open connection.

       MEMCACHED_BEHAVIOR_SERVER_FAILURE_LIMIT
           Set this value to enable the server be removed after continuous
           MEMCACHED_BEHAVIOR_SERVER_FAILURE_LIMIT times connection failure.

       MEMCACHED_BEHAVIOR_IO_MSG_WATERMARK
           Set this value to tune the number of messages that may be sent before libmemcached
           should start to automatically drain the input queue. Setting this value to high, may
           cause libmemcached to deadlock (trying to send data, but the send will block because
           the input buffer in the kernel is full).

       MEMCACHED_BEHAVIOR_IO_BYTES_WATERMARK
           Set this value to tune the number of bytes that may be sent before libmemcached should
           start to automatically drain the input queue (need at least 10 IO requests sent
           without reading the input buffer). Setting this value to high, may cause libmemcached
           to deadlock (trying to send data, but the send will block because the input buffer in
           the kernel is full).

       MEMCACHED_BEHAVIOR_IO_KEY_PREFETCH
           The binary protocol works a bit different than the textual protocol in that a multiget
           is implemented as a pipe of single get-operations which are sent to the server in a
           chunk. If you are using large multigets from your application, you may improve the
           latency of the gets by setting this value so you send out the first chunk of requests
           when you hit the specified limit.  It allows the servers to start processing the
           requests to send the data back while the rest of the requests are created and sent to
           the server.

       MEMCACHED_BEHAVIOR_NOREPLY
           Set this value to specify that you really don't care about the result from your
           storage commands (set, add, replace, append, prepend).

       MEMCACHED_BEHAVIOR_NUMBER_OF_REPLICAS
           If you just want "a poor mans HA", you may specify the numbers of replicas
           libmemcached should store of each item (on different servers).  This replication does
           not dedicate certain memcached servers to store the replicas in, but instead it will
           store the replicas together with all of the other objects (on the 'n' next servers
           specified in your server list).

       MEMCACHED_BEHAVIOR_RANDOMIZE_REPLICA_READ
           Allows randomizing the replica reads starting point. Normally the read is done from
           primary server and in case of miss the read is done from primary + 1, then primary + 2
           all the way to 'n' replicas. If this option is set on the starting point of the
           replica reads is randomized between the servers.  This allows distributing read load
           to multiple servers with the expense of more write traffic.

       MEMCACHED_BEHAVIOR_CORK
           Enable TCP_CORK behavior. This is only available as an option Linux.
           MEMCACHED_NO_SERVERS is returned if no servers are available to test with.
           MEMCACHED_NOT_SUPPORTED is returned if we were not able to determine if support was
           available. All other responses then MEMCACHED_SUCCESS report an error of some sort.
           This behavior also enables MEMCACHED_BEHAVIOR_TCP_NODELAY when set.

       MEMCACHED_BEHAVIOR_KEEPALIVE
           Enable TCP_KEEPALIVE behavior.

       MEMCACHED_BEHAVIOR_KEEPALIVE_IDLE
           Specify time, in seconds, to mark a connection as idle. This is only available as an
           option Linux.

       MEMCACHED_BEHAVIOR_SOCKET_SEND_SIZE
           Find the current size of SO_SNDBUF. A value of 0 means either an error occurred or no
           hosts were available. It is safe to assume system default if this occurs.

       MEMCACHED_BEHAVIOR_SOCKET_RECV_SIZE
           Find the current size of SO_RCVBUF. A value of 0 means either an error occurred or no
           hosts were available. It is safe to assume system default if this occurs.

       MEMCACHED_BEHAVIOR_SERVER_FAILURE_LIMIT
           This number of times a host can have an error before it is disabled.

       MEMCACHED_BEHAVIOR_AUTO_EJECT_HOSTS
           If enabled any hosts which have been flagged as disabled will be removed from the list
           of servers in the memcached_st structure. This must be used in combination with
           MEMCACHED_BEHAVIOR_SERVER_FAILURE_LIMIT.

       MEMCACHED_BEHAVIOR_RETRY_TIMEOUT
           When enabled a host which is problematic will only be checked for usage based on the
           amount of time set by this behavior.

RETURN

       memcached_behavior_get() returns either the current value of the get, or 0 or 1 on simple
       flag behaviors (1 being enabled). memcached_behavior_set() returns failure or success.

NOTES

       memcached_behavior_set() in version .17 was changed from taking a pointer to data value,
       to taking a uin64_t.

HOME

       To find out more information please check: <https://launchpad.net/libmemcached>

AUTHOR

       Brian Aker, <brian@tangent.org>

SEE ALSO

       memcached(1) libmemcached(3) memcached_strerror(3)

perl v5.26.0                                2017-Memcached::libmemcached::memcached_behavior(3pm)