module Nn_state: sig .. end
State manager: Provide the logical view of the state, and forward changes
to the database and to the nameslaves (2-phase commit)
type Plasma_util.errno
exception Transaction_error of errno
class type shared_state_t = object .. end
This object exists once in the nn_master container, and collects
information from not yet committed views (such as which ID's are
used), so that the views can avoid clashes between each other.
type [ `Balanced of int ]
- `Balanced factor: Blocks are allocated on all datanodes,
so that the nodes fill up similarly. The int is the
replication factor
type Nn_db.modification Queue.t
A journal is a queue of database modifications. Journals are the
entities that are sent to the slaves
class type view_t = object .. end
A view is a high-level transaction, involving both the local db and
the slaves
class type ds_view_t = object .. end
View on datastore state
type
|
td_idlist : int list; |
|
td_safetrans_id : int64; |
|
td_safetrans_secret : int64; |
|
td_safetrans_tmo : int64; |
}
class type bm_view_t = object .. end
View on blockmap state:
class type inode_view_t = object .. end
The following classes are used as follows: First, a
shared_state
is created. This object is passed on as arguments to the view
objects. The views, if all connected with the same
shared_state,
can be committed in one go (in
Nn_commit).
class shared_state : Unixqueue.event_system -> Nn_config.nn_node_config -> int -> string -> shared_state_t
class ds_view : shared_state_t -> ds_view_t
class bm_view : shared_state_t -> bm_view_t
class inode_view : shared_state_t -> inode_view_t
val encap_time : float -> Pfs_rpcapi_aux.time
Turn the time (as seconds since epoch) into the RPC version
