summaryrefslogtreecommitdiffstats
path: root/doc/mon
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-21 11:54:28 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-21 11:54:28 +0000
commite6918187568dbd01842d8d1d2c808ce16a894239 (patch)
tree64f88b554b444a49f656b6c656111a145cbbaa28 /doc/mon
parentInitial commit. (diff)
downloadceph-e6918187568dbd01842d8d1d2c808ce16a894239.tar.xz
ceph-e6918187568dbd01842d8d1d2c808ce16a894239.zip
Adding upstream version 18.2.2.upstream/18.2.2
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'doc/mon')
-rw-r--r--doc/mon/README.txt27
-rw-r--r--doc/mon/paxos-call-chain.dot82
2 files changed, 109 insertions, 0 deletions
diff --git a/doc/mon/README.txt b/doc/mon/README.txt
new file mode 100644
index 000000000..fa1bf791a
--- /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 000000000..cdca200f0
--- /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];
+}