diff options
Diffstat (limited to 'doc/mon')
| -rw-r--r-- | doc/mon/README.txt | 27 | ||||
| -rw-r--r-- | doc/mon/paxos-call-chain.dot | 82 |
2 files changed, 109 insertions, 0 deletions
diff --git a/doc/mon/README.txt b/doc/mon/README.txt new file mode 100644 index 00000000..fa1bf791 --- /dev/null +++ b/doc/mon/README.txt @@ -0,0 +1,27 @@ +paxos-call-chain.dot describes to some detail the call chain involved in the +Paxos algorithm, paying special consideration to the messages involved. + +This information is not easily obtainable by Doxygen, as it does not follow +the call chain when messages are involved, since it becomes an async workflow. + +To obtain the graph one should run + + dot -T<format> paxos-call-chain.dot -o paxos-call-chain.<format> + +e.g., + + dot -Tps paxos-call-chain.dot -o paxos-call-chain.ps + +or + + dot -Tpng paxos-call-chain.dot -o paxos-call-chain.png + +It should do the trick. + +Also, for future reference, we consider that: + - boxed nodes refer to the Leader; + - elliptical nodes refer to the Peon; + - diamond shaped nodes refer to state changes; + - dotted lines illustrate a message being sent from the Leader to the Peon, + or vice-versa. + diff --git a/doc/mon/paxos-call-chain.dot b/doc/mon/paxos-call-chain.dot new file mode 100644 index 00000000..cdca200f --- /dev/null +++ b/doc/mon/paxos-call-chain.dot @@ -0,0 +1,82 @@ +digraph Paxos { + concentrate=true +// subgraph cluster0 { + collect -> state_recovering; + collect -> send_mmp_collect -> handle_collect [style=dotted]; + handle_collect -> send_mmp_last; + send_mmp_last -> handle_last [style=dotted]; + handle_last -> collect [label="collect(last_pn)"]; + handle_last -> send_mmp_commit; + handle_last -> state_active; + handle_last -> begin; + handle_last -> extend_lease; + +// color=grey; +// style=filled; +// label="Post-Election call chain"; +// } + + election_finished -> leader_init; + leader_init -> collect [label="collect(0)"]; + send_mmp_commit -> handle_commit [style=dotted]; + + begin -> state_updating; + begin -> send_mmp_begin; + begin -> commit; + + send_mmp_begin -> handle_begin [style=dotted]; + handle_begin -> state_updating; + handle_begin -> send_mmp_accept; + send_mmp_accept -> handle_accept [style=dotted]; + + handle_accept -> extend_lease; + handle_accept -> state_active; + handle_accept -> commit; + + extend_lease -> send_mmp_lease; + send_mmp_lease -> handle_lease [style=dotted]; + handle_lease -> state_active; + handle_lease -> send_mmp_lease_ack; + send_mmp_lease_ack -> handle_lease_ack [style=dotted]; + + commit -> send_mmp_commit; + commit -> "last_committed++" [shape=box]; + send_mmp_commit -> handle_commit [style=dotted]; + + handle_commit -> store_state; + + propose_pending -> propose_new_value; + propose_new_value -> begin; + + election_finished [label="Election Finished", shape=box, bgcolor=grey, style=filled]; + collect [label="collect()", shape=box]; + commit [label="commit()", shape=box]; + begin [label="begin()", shape=box]; + extend_lease [label="extend_lease()", shape=box]; + store_state [label="store_state()"]; // peon + + propose_pending [label="PaxosService::propose_pending()"]; + propose_new_value [label="propose_new_value"]; + + send_mmp_collect [label="send(OP_COLLECT)", shape=box]; + send_mmp_last [label="send(OP_LAST)"]; + send_mmp_commit [label="send(OP_COMMIT)", shape=box]; + send_mmp_begin [label="send(OP_BEGIN)", shape=box]; + send_mmp_accept [label="send(OP_ACCEPT)"]; + send_mmp_lease [label="send(OP_LEASE)", shape=box]; + send_mmp_lease_ack [label="send(OP_LEASE_ACK)"]; + + handle_collect [label="handle_collect()"]; + handle_last [label="handle_last()", shape=box]; + handle_begin [label="handle_begin()"]; + handle_accept [label="handle_accept()", shape=box]; + handle_lease [label="handle_lease()"]; + handle_lease_ack [label="handle_lease_ack()", shape=box]; + handle_commit [label="handle_commit()"]; + + leader_init [label="Paxos::leader_init()", shape=box]; + + state_recovering [label="RECOVERING", shape=diamond]; + state_active [label="ACTIVE", shape=diamond]; + state_updating [label="UPDATING", shape=diamond]; +} |