tursom/memgraph
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Make raft work in the happy path

Browse Source
This commit is contained in:
Tyler Neely 2022-07-14 19:57:52 +00:00
parent 63beeb8771
commit 3466c15f76
1 changed files with 9 additions and 6 deletions

15
tests/simulation/raft.cpp
View File

@ -177,6 +177,7 @@ class Server {
}
void BroadcastAppendEntries(std::map<Address, FollowerTracker> &followers) {
Log("leader broadcasting, total log size is ", state_.log.size());
for (auto &[address, follower] : followers) {
LogIndex index = follower.confirmed_contiguous_index;
@ -187,7 +188,7 @@ class Server {
AppendRequest ar{
.term = state_.term,
.last_log_index = index,
.last_log_term = TermAtIndex(index),
.last_log_term = PreviousTermFromIndex(index),
.entries = entries,
.leader_commit = state_.commit_index,
};
@ -204,11 +205,11 @@ class Server {
return io_.Rand(time_distrib);
}
Term TermAtIndex(LogIndex index) {
if (state_.log.size() <= index) {
Term PreviousTermFromIndex(LogIndex index) {
if (state_.log.size() <= index + 1) {
return 0;
} else {
auto &[term, data] = state_.log.at(index);
auto &[term, data] = state_.log.at(index - 1);
return term;
}
}
@ -300,7 +301,6 @@ class Server {
// Leaders (re)send AppendRequest to followers.
std::optional<Role> Cron(Leader &leader) {
// TODO time-out client requests if we haven't made progress after some threshold
Log("leader broadcasting");
BroadcastAppendEntries(leader.followers);
return std::nullopt;
}
@ -432,6 +432,8 @@ class Server {
leader.pending_client_requests.push_back(pcr);
BroadcastAppendEntries(leader.followers);
// TODO add message to pending requests buffer, reply asynchronously
return std::nullopt;
}
@ -497,7 +499,8 @@ class Server {
if (req.last_log_index != LastLogIndex()) {
Log("req.last_log_index is above our last applied log index");
} else if (req.last_log_term != LastLogTerm()) {
Log("req.last_log_term differs from our leader term at that slot");
Log("req.last_log_term differs from our leader term at that slot, expected: ", LastLogTerm(), " but got ",
req.last_log_term);
} else {
// happy path
Log("Follower applying batch of entries to log of size ", req.entries.size());