diff options
Diffstat (limited to 'doc/source/deployment_guide.rst')
| -rw-r--r-- | doc/source/deployment_guide.rst | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/doc/source/deployment_guide.rst b/doc/source/deployment_guide.rst index 0417e6a5c..f6fdfbd2a 100644 --- a/doc/source/deployment_guide.rst +++ b/doc/source/deployment_guide.rst @@ -489,6 +489,29 @@ that have available RAM and CPU. Typically Memcached is run on the proxy servers. The ``memcache_servers`` config option in the ``proxy-server.conf`` should contain all memcached servers. +************************* +Shard Range Listing Cache +************************* + +When a container gets :ref:`sharded<sharding_doc>` the root container will still be the +primary entry point to many container requests, as it provides the list of shards. +To take load off the root container Swift by default caches the list of shards returned. + +As the number of shards for a root container grows to more than 3k the memcache default max +size of 1MB can be reached. Care is needed to keep an eye on the current value or resize it +to something like 5MB. + +Memcache has a ``stats sizes`` option that can point out the current size usage. As this +reaches the current max an increase might be in order:: + + # telnet <memcache server> 11211 + > stats sizes + STAT 160 2 + STAT 448 1 + STAT 576 1 + END + + ----------- System Time ----------- |