JBoss Community Archive (Read Only)

Infinispan 6.0

Memcached Server


As of Infinispan 5.3, the supported way to start an Infinispan Memcached server is via the Infinispan Server. This page details differences between the original Memcached server functionality and the Infinispan implementation

Command Clarifications

Flush All

Even in a clustered environment, flush_all command leads to the clearing of the Infinispan Memcached server where the call lands. There's no attempt to propagate this flush to other nodes in the cluster. This is done so that flush_all with delay use case can be reproduced with the Infinispan Memcached server. The aim of passing a delay to flush_all is so that different Memcached servers in a full can be flushed at different times, and hence avoid overloading the database with requests as a result of all Memcached servers being empty. For more info, check the Memcached text protocol section on flush_all.

Unsupported Features

This section explains those parts of the memcached text protocol that for one reason or the other, are not currently supported by the Infinispan based memcached implementation.

Individual Stats

Due to difference in nature between the original memcached implementation which is C/C++ based and the Infinispan implementation which is Java based, there're some general purpose stats that are not supported. For these unsupported stats, Infinispan memcached server always returns 0.

Here's the list of currently unsupported stats:

  • pid

  • pointer_size

  • rusage_user

  • rusage_system

  • bytes

  • curr_connections

  • total_connections

  • connection_structures

  • auth_cmds

  • auth_errors

  • limit_maxbytes

  • threads

  • conn_yields

  • reclaimed

Statistic Settings

The settings statistics section of the text protocol has not been implemented due to its volatility.

Settings with Arguments Parameter

Since the arguments that can be send to the Memcached server are not documented, Infinispan Memcached server does not support passing any arguments to stats command. If any parameters are passed, the Infinispan Memcached server will respond with a CLIENT_ERROR.

Delete Hold Time Parameter

Memcached does no longer honor the optional hold time parameter to delete command and so the Infinispan based memcached server does not implement such feature either.

Verbosity Command

Verbosity command is not supported since Infinispan logging cannot be simplified to defining the logging level alone.

JBoss.org Content Archive (Read Only), exported from JBoss Community Documentation Editor at 2020-03-11 09:40:30 UTC, last content change 2013-07-08 13:55:18 UTC.