The constants below are defined by this extension, and will only be available when the extension has either been compiled into PHP or dynamically loaded at runtime.
Memcached::OPT_COMPRESSION
Enables or disables payload compression. When enabled, item values longer than a certain threshold (currently 100 bytes) will be compressed during storage and decompressed during retrieval transparently.
Type: boolean, default: TRUE.
Memcached::OPT_SERIALIZER
Specifies the serializer to use for serializing non-scalar values.
The valid serializers are Memcached::SERIALIZER_PHP
or Memcached::SERIALIZER_IGBINARY. The latter is
supported only when memcached is configured with
--enable-memcached-igbinary option and the
igbinary extension is loaded.
Type: integer, default: Memcached::SERIALIZER_PHP.
Memcached::SERIALIZER_PHP
The default PHP serializer.
Memcached::SERIALIZER_IGBINARY
The » igbinary serializer. Instead of textual representation it stores PHP data structures in a compact binary form, resulting in space and time gains.
Memcached::SERIALIZER_JSON
The JSON serializer. Requires PHP 5.2.10+.
Memcached::OPT_PREFIX_KEY
This can be used to create a "domain" for your item keys. The value specified here will be prefixed to each of the keys. It cannot be longer than 128 characters and will reduce the maximum available key size. The prefix is applied only to the item keys, not to the server keys.
Type: string, default: "".
Memcached::OPT_HASH
Specifies the hashing algorithm used for the item keys. The valid
values are supplied via Memcached::HASH_* constants.
Each hash algorithm has its advantages and its disadvantages. Go with the
default if you don't know or don't care.
Type: integer, default: Memcached::HASH_DEFAULT
Memcached::HASH_DEFAULT
The default (Jenkins one-at-a-time) item key hashing algorithm.
Memcached::HASH_MD5
MD5 item key hashing algorithm.
Memcached::HASH_CRC
CRC item key hashing algorithm.
Memcached::HASH_FNV1_64
FNV1_64 item key hashing algorithm.
Memcached::HASH_FNV1A_64
FNV1_64A item key hashing algorithm.
Memcached::HASH_FNV1_32
FNV1_32 item key hashing algorithm.
Memcached::HASH_FNV1A_32
FNV1_32A item key hashing algorithm.
Memcached::HASH_HSIEH
Hsieh item key hashing algorithm.
Memcached::HASH_MURMUR
Murmur item key hashing algorithm.
Memcached::OPT_DISTRIBUTION
Specifies the method of distributing item keys to the servers. Currently supported methods are modulo and consistent hashing. Consistent hashing delivers better distribution and allows servers to be added to the cluster with minimal cache losses.
Type: integer, default: Memcached::DISTRIBUTION_MODULA.
Memcached::DISTRIBUTION_MODULA
Modulo-based key distribution algorithm.
Memcached::DISTRIBUTION_CONSISTENT
Consistent hashing key distribution algorithm (based on libketama).
Memcached::OPT_LIBKETAMA_COMPATIBLE
Enables or disables compatibility with libketama-like behavior. When enabled, the item key hashing algorithm is set to MD5 and distribution is set to be weighted consistent hashing distribution. This is useful because other libketama-based clients (Python, Ruby, etc.) with the same server configuration will be able to access the keys transparently.
Note:
It is highly recommended to enable this option if you want to use consistent hashing, and it may be enabled by default in future releases.
Type: boolean, default: FALSE.
Memcached::OPT_BUFFER_WRITES
Enables or disables buffered I/O. Enabling buffered I/O causes storage commands to "buffer" instead of being sent. Any action that retrieves data causes this buffer to be sent to the remote connection. Quitting the connection or closing down the connection will also cause the buffered data to be pushed to the remote connection.
Type: boolean, default: FALSE.
Memcached::OPT_BINARY_PROTOCOL
Enable the use of the binary protocol. Please note that you cannot toggle this option on an open connection.
Type: boolean, default: FALSE.
Memcached::OPT_NO_BLOCK
Enables or disables asynchronous I/O. This is the fastest transport available for storage functions.
Type: boolean, default: FALSE.
Memcached::OPT_TCP_NODELAY
Enables or disables the no-delay feature for connecting sockets (may be faster in some environments).
Type: boolean, default: FALSE.
Memcached::OPT_SOCKET_SEND_SIZE
The maximum socket send buffer in bytes.
Type: integer, default: varies by platform/kernel configuration.
Memcached::OPT_SOCKET_RECV_SIZE
The maximum socket receive buffer in bytes.
Type: integer, default: varies by platform/kernel configuration.
Memcached::OPT_CONNECT_TIMEOUT
In non-blocking mode this set the value of the timeout during socket connection, in milliseconds.
Type: integer, default: 1000.
Memcached::OPT_RETRY_TIMEOUT
The amount of time, in seconds, to wait until retrying a failed connection attempt.
Type: integer, default: 0.
Memcached::OPT_SEND_TIMEOUT
Socket sending timeout, in microseconds. In cases where you cannot use non-blocking I/O this will allow you to still have timeouts on the sending of data.
Type: integer, default: 0.
Memcached::OPT_RECV_TIMEOUT
Socket reading timeout, in microseconds. In cases where you cannot use non-blocking I/O this will allow you to still have timeouts on the reading of data.
Type: integer, default: 0.
Memcached::OPT_POLL_TIMEOUT
Timeout for connection polling, in milliseconds.
Type: integer, default: 1000.
Memcached::OPT_CACHE_LOOKUPS
Enables or disables caching of DNS lookups.
Type: boolean, default: FALSE.
Memcached::OPT_SERVER_FAILURE_LIMIT
Specifies the failure limit for server connection attempts. The server will be removed after this many continuous connection failures.
Type: integer, default: 0.
Memcached::HAVE_IGBINARY
Indicates whether igbinary serializer support is available.
Type: boolean.
Memcached::HAVE_JSON
Indicates whether JSON serializer support is available.
Type: boolean.
Memcached::GET_PRESERVE_ORDER
A flag for Memcached::getMulti() and Memcached::getMultiByKey() to ensure that the keys are returned in the same order as they were requested in. Non-existing keys get a default value of NULL.
Memcached::RES_SUCCESS
The operation was successful.
Memcached::RES_FAILURE
The operation failed in some fashion.
Memcached::RES_HOST_LOOKUP_FAILURE
DNS lookup failed.
Memcached::RES_UNKNOWN_READ_FAILURE
Failed to read network data.
Memcached::RES_PROTOCOL_ERROR
Bad command in memcached protocol.
Memcached::RES_CLIENT_ERROR
Error on the client side.
Memcached::RES_SERVER_ERROR
Error on the server side.
Memcached::RES_WRITE_FAILURE
Failed to write network data.
Memcached::RES_DATA_EXISTS
Failed to do compare-and-swap: item you are trying to store has been modified since you last fetched it.
Memcached::RES_NOTSTORED
Item was not stored: but not because of an error. This normally means that either the condition for an "add" or a "replace" command wasn't met, or that the item is in a delete queue.
Memcached::RES_NOTFOUND
Item with this key was not found (with "get" operation or "cas" operations).
Memcached::RES_PARTIAL_READ
Partial network data read error.
Memcached::RES_SOME_ERRORS
Some errors occurred during multi-get.
Memcached::RES_NO_SERVERS
Server list is empty.
Memcached::RES_END
End of result set.
Memcached::RES_ERRNO
System error.
Memcached::RES_BUFFERED
The operation was buffered.
Memcached::RES_TIMEOUT
The operation timed out.
Memcached::RES_BAD_KEY_PROVIDED
Bad key.
Memcached::RES_CONNECTION_SOCKET_CREATE_FAILURE
Failed to create network socket.
Memcached::RES_PAYLOAD_FAILURE
Payload failure: could not compress/decompress or serialize/unserialize the value.