Do not delete block if just a single replication error. Write TODO stuff.

This commit is contained in:
Alex 2020-04-22 19:25:15 +00:00
parent 8971f34c81
commit 231cb32955
2 changed files with 36 additions and 18 deletions

34
TODO
View file

@ -1,18 +1,36 @@
Replication
-----------
Finish the thing that sends blocks to other nodes if needed before deleting them locally.
Testing
-------
How are we going to test that our replication method works correctly?
We will have to introduce lots of dummy data and then add/remove nodes many times.
Repair:
- re-propagate block ref table to rc
Improvements
------------
Membership: keep IP addresses of failed nodes and try to reping them regularly
RPC client/server: do not go through the serialization+HTTP+TLS+deserialization when doing a request to ourself.
RPC requests: unify quorum + timeout in a "RequestStrategy" class,
and add to the request strategy whether or not the request should continue in the background
once `quorum` valid responses have been received
To do list
----------
Attaining S3 compatibility
--------------------------
- table for access keys
- S3 request signature verification
- api_server following the S3 semantics for get/put/delete
- implement object listing
- possibly other necessary endpoints ?
Lower priority
--------------
- less a priority: hinted handoff
- repair: re-propagate block ref table to rc
- FIXME in rpc_server when garage shuts down and futures can be interrupted
(tokio::spawn should be replaced by a new function background::spawn_joinable)

View file

@ -278,25 +278,25 @@ impl BlockManager {
let who_needs = join_all(who_needs_fut).await;
let mut need_nodes = vec![];
let mut errors = 0;
for (node, needed) in who.into_iter().zip(who_needs.iter()) {
match needed {
Ok(Message::NeedBlockReply(true)) => {
need_nodes.push(node);
}
Err(_) => {
errors += 1;
Err(e) => {
return Err(Error::Message(format!(
"Should delete block, but unable to confirm that all other nodes that need it have it: {}",
e
)));
}
_ => {
return Err(Error::Message(format!(
"Unexpected response to NeedBlockQuery RPC"
)));
}
_ => (),
}
}
if errors > (garage.system.config.data_replication_factor - 1) / 2 {
return Err(Error::Message(format!(
"Should delete block, but not enough nodes confirm that they have it."
)));
}
if need_nodes.len() > 0 {
let put_block_message = self.read_block(hash).await?;
let put_responses = self