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+Meta translator
+===============
+
+Introduction
+------------
+
+Meta xlator provides an interface similar to the Linux procfs, for GlusterFS
+runtime and configuration. This document lists some useful information about
+GlusterFS internals that could be accessed via the meta xlator. This is not
+exhaustive at the moment. Contributors are welcome to improve this.
+
+Note: Meta xlator is loaded automatically in the client graph, ie. in the
+mount process' graph.
+
+### GlusterFS native mount version
+
+>[root@trantor codebase]# cat $META/version
+>{
+> "Package Version": "3.7dev"
+>}
+
+### Listing of some files under the `meta` folder
+
+>[root@trantor codebase]# mount -t glusterfs trantor:/vol /mnt/fuse
+>[root@trantor codebase]# ls $META
+>cmdline frames graphs logging mallinfo master measure_latency process_uuid version
+
+### GlusterFS' process identifier
+
+>[root@trantor codebase]# cat $META/process_uuid
+>trantor-11149-2014/07/25-18:48:50:468259
+>
+This identifier appears in connection establishment log messages.
+For eg.,
+
+>[2014-07-25 18:48:49.017927] I [server-handshake.c:585:server_setvolume] 0-vol-server: accepted client from trantor-11087-2014/07/25-18:48:48:779656-vol-client-0-0-0 (version: 3.7dev)
+>
+
+### GlusterFS command line
+
+>[root@trantor codebase]# cat $META/cmdline
+>{
+> "Cmdlinestr": "/usr/local/sbin/glusterfs --volfile-server=trantor --volfile-id=/vol /mnt/fuse"
+>}
+
+### GlusterFS volume graph
+
+The following directory structure reveals the way xlators are stacked in a
+graph like fashion. Each (virtual) file under a xlator directory provides
+runtime information of that xlator. For eg. 'name' contains the name of the
+xlator.
+
+```
+/mnt/fuse/.meta/graphs/active
+|-- meta-autoload
+| |-- history
+| |-- meminfo
+| |-- name
+| |-- options
+| |-- private
+| |-- profile
+| |-- subvolumes
+| | `-- 0 -> ../../vol
+| |-- type
+| `-- view
+|-- top -> meta-autoload
+|-- vol
+| |-- history
+| |-- meminfo
+| |-- name
+| |-- options
+| | |-- count-fop-hits
+| | `-- latency-measurement
+| |-- private
+| |-- profile
+| |-- subvolumes
+| | `-- 0 -> ../../vol-md-cache
+| |-- type
+| `-- view
+|-- vol-client-0
+| |-- history
+| |-- meminfo
+| |-- name
+| |-- options
+| | |-- client-version
+| | |-- clnt-lk-version
+| | |-- fops-version
+| | |-- password
+| | |-- ping-timeout
+| | |-- process-uuid
+| | |-- remote-host
+| | |-- remote-subvolume
+| | |-- send-gids
+| | |-- transport-type
+| | |-- username
+| | |-- volfile-checksum
+| | `-- volfile-key
+| |-- private
+| |-- profile
+| |-- subvolumes
+| |-- type
+| `-- view
+|-- vol-client-1
+| |-- history
+| |-- meminfo
+| |-- name
+| |-- options
+| | |-- client-version
+| | |-- clnt-lk-version
+| | |-- fops-version
+| | |-- password
+| | |-- ping-timeout
+| | |-- process-uuid
+| | |-- remote-host
+| | |-- remote-subvolume
+| | |-- send-gids
+| | |-- transport-type
+| | |-- username
+| | |-- volfile-checksum
+| | `-- volfile-key
+| |-- private
+| |-- profile
+| |-- subvolumes
+| |-- type
+| `-- view
+|-- vol-dht
+| |-- history
+| |-- meminfo
+| |-- name
+| |-- options
+| |-- private
+| |-- profile
+| |-- subvolumes
+| | |-- 0 -> ../../vol-client-0
+| | `-- 1 -> ../../vol-client-1
+| |-- type
+| `-- view
+|-- volfile
+|-- vol-io-cache
+| |-- history
+| |-- meminfo
+| |-- name
+| |-- options
+| |-- private
+| |-- profile
+| |-- subvolumes
+| | `-- 0 -> ../../vol-read-ahead
+| |-- type
+| `-- view
+|-- vol-md-cache
+| |-- history
+| |-- meminfo
+| |-- name
+| |-- options
+| |-- private
+| |-- profile
+| |-- subvolumes
+| | `-- 0 -> ../../vol-open-behind
+| |-- type
+| `-- view
+|-- vol-open-behind
+| |-- history
+| |-- meminfo
+| |-- name
+| |-- options
+| |-- private
+| |-- profile
+| |-- subvolumes
+| | `-- 0 -> ../../vol-quick-read
+| |-- type
+| `-- view
+|-- vol-quick-read
+| |-- history
+| |-- meminfo
+| |-- name
+| |-- options
+| |-- private
+| |-- profile
+| |-- subvolumes
+| | `-- 0 -> ../../vol-io-cache
+| |-- type
+| `-- view
+|-- vol-read-ahead
+| |-- history
+| |-- meminfo
+| |-- name
+| |-- options
+| |-- private
+| |-- profile
+| |-- subvolumes
+| | `-- 0 -> ../../vol-write-behind
+| |-- type
+| `-- view
+`-- vol-write-behind
+ |-- history
+ |-- meminfo
+ |-- name
+ |-- options
+ |-- private
+ |-- profile
+ |-- subvolumes
+ | `-- 0 -> ../../vol-dht
+ |-- type
+ `-- view
+
+```