Summary:
The documentation includes `std` exceptions like `std::bad_alloc` or
`std::system_error`, for which there's probably nothing we can do. This
may seem unnecessary, but it will be really helpful when writing the C
API for interfacing with custom modules and plugins, as well as when
switching to storage v2 API.
In general, we should start updating the documentation of functions
which may throw exceptions. This ought to be enforced in code review, so
that the implementation and documentation are kept in sync.
Reviewers: mferencevic, mtomic, msantl
Reviewed By: mferencevic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2288
Summary:
Stream queries to the output table.
For effective output streaming, a simple operator, `OutputTableStream` is implemented which fetches and
produces a single row on each Pull.
Reviewers: teon.banek
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2099
Summary: Forward declare the needed struct and include in the correct file.
Reviewers: ipaljak
Reviewed By: ipaljak
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2110
Summary:
HA should now support constraints in the same way the SM version does.
I only tested this thing manually, but I plan to add a new integration test for
this also.
Reviewers: ipaljak, vkasljevic, mferencevic
Reviewed By: ipaljak, mferencevic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2083
Summary:
Preparing unique constraint code to be implemented in HA. To do so, I'm
moving everything to `stograge/common/` folder. I also added a new header,
`gid.hpp` which does a `ifdef` include of the correct `gid.hpp` based on the
product.
Reviewers: ipaljak, mferencevic, vkasljevic, teon.banek
Reviewed By: mferencevic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2079
Summary:
This change introduces dumping of indices keys. During the dump process,
an internal label is assigned to each vertex and index on vertex's
internal property id is created for faster matching during edge creation.
Reviewers: teon.banek
Reviewed By: teon.banek
Subscribers: msantl, pullbot
Differential Revision: https://phabricator.memgraph.io/D2046
Summary:
Prior to this change, a huge query was returned by DumpGenerator that
dumped the entire graph. This change split the single query to multiple
queries, each dumping a single vertex/edge. For easier vertex matching
when dumping edge, an internal property id is assigned to each vertex and
removed after the whole graph is dumped.
Reviewers: teon.banek
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2038
Summary:
There will be a lot of leftover files, execute the following commands inside
`src/` to remove them:
```
git clean -xf
rm -r rpc/ storage/single_node_ha/rpc/
```
Reviewers: teon.banek
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2011
Summary:
This is still in progress.
As reported in
https://app.asana.com/0/743890251333732/971034572323525/f
memgraph distributed fails when the snapshot that it tries to recover from is
invalid. Instead of inheritance of `StorageGc` this diff adds composition and we
don't try to register a rpc server after the initialization.
Reviewers: ipaljak, vkasljevic, mtomic
Reviewed By: vkasljevic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1930
Summary:
Case with existence constraints is about 8-9% slower then case without
existence constraints. Before this diff that difference was about 15-16%.
Reviewers: msantl, ipaljak
Reviewed By: ipaljak
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1917
Summary:
UniqueLabelPropertyConstraint defines label + property restriction on vertices.
Label + Property + PropertyValue for that property must be unique at any given moment.
Reviewers: msantl, ipaljak
Reviewed By: msantl
Subscribers: mferencevic, pullbot
Differential Revision: https://phabricator.memgraph.io/D1884
Summary:
`SHOW STORAGE STATS` when executed in a Raft cluster should return
stats for each member of the cluster.
`StorageStats` starts a RPC server on each member of the cluster that answers
about its local storage stats.
The query can be invoked only on the current leader, the leader sends a request
to each peer and shows the results it gets. If some peers don't answer within 1
second, stats for those peers won't be shown.
The new output can be seen here: P27
Reviewers: ipaljak, mferencevic
Reviewed By: ipaljak
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1907
Summary:
Added index creation and deletion handling in StateDelta.
Also included an integration test that creates an index and makes sure that it
gets replicated by killing each peer eventually causing a leader re-election.
Reviewers: ipaljak
Reviewed By: ipaljak
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1886
Summary: `DataRpcClient` and `DataRpcServer` now work with both old and new record. This will be needed later when I replace `Cache` with `LruCache`.
Reviewers: msantl, teon.banek, ipaljak
Reviewed By: msantl, teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1875
Summary:
Existence constraint ensures that all nodes with certain label have a certain property.
`ExistenceRule` defines label -> properties rule and `ExistenceConstraints` manages all
constraints.
Reviewers: msantl, ipaljak, teon.banek, mferencevic
Reviewed By: msantl, teon.banek, mferencevic
Subscribers: mferencevic, pullbot
Differential Revision: https://phabricator.memgraph.io/D1797
Summary:
During the following scenario:
- start a HA cluster with 3 machines
- find the leader and start sending queries
- SIGTERM the leader but leave other 2 machines untouched
The leader would be stuck in the shutdown phase.
This was happening because during the shutdown phase of the Bolt server, a
`graph_db_accessor` would try to commit a transaction after we've already shut
down Raft server. Raft, although not running, is still thinking it's in the
Leader mode. Tx Engine calls the `SafeToCommit` method to Commit transactions,
and ends up in an infinite loop.
Since Raft was shut down it won't handle any of the incoming RPCs and won't
change it's mode.
The fix here is to shut down the Bolt server before Raft, so we don't have any
pending commits once Raft is shut down.
Reviewers: ipaljak
Reviewed By: ipaljak
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1853
Summary:
Added a new awesome function called `storageInfo`. This function
returns a list of key-value pairs containing the following (useful?)
information:
* number of vertices
* number of edges
* average degree
* memory usage
* disk usage
The current implementation is in `awesome_memgraph_functions` but it will end up
as a separate clause for better access control.
Reviewers: teon.banek, mtomic, mferencevic
Reviewed By: teon.banek
Subscribers: pullbot, buda
Differential Revision: https://phabricator.memgraph.io/D1850
Summary:
In this part of log compaction for raft, I've implemented snapshooting
and snapshot recovery. I've also refactored the code a bit, so `RaftServer` now
has a pointer to the `GraphDb` and it can do some things by itself.
Log compaction requires some further work. Since snapshooting isn't synchronous
between peers, and each peer can work at their own pace, once we've compacted
the log so that the next log to be sent to peer `x` isn't available anymore, we
need to send the snapshot over the wire. This means that the next part will
contain the `InstallSnapshotRPC` and then maybe one more that will implement the
logic of sending `LogEntry` or the whole snapshot.
Reviewers: ipaljak
Reviewed By: ipaljak
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1834
Summary:
Once a leader loses it's leadership, in order to handle hanging
transactions, we reset the storage and the transaction engine.
This requires to re-apply all the commited entries from the log.
Once we add snapshot (log compaction) we would need to do that also.
One thing to have in mind is the `election_timeout_min` parameter. If it's set
too low it could trigger leader re-election too often.
Reviewers: ipaljak
Reviewed By: ipaljak
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1822
Summary:
Before I wrongly assumed `Shutdown` will always be called on Cursors and
removed BFS subcursors there. Now it is done using transactional cache clean-up
mechanism. There's a separate clean-up for `BfsSubcursorStorage` (for actual
subcursors) and `BfsRpcServer` (for database accessors created by the server).
I've changed `BfsRpcServer` to have a `GraphDbAccessor` per transaction,
instead of per `BfsSubcursor`. Mainly because there is no reliable way to check
if the transaction tied to the accessor has expired as it is not safe to call
`transaction_id` method (since `GraphDbAccessor` is holding only a reference to
`Transaction` object).
Reviewers: teon.banek, mferencevic
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1792
Summary:
Creating Raft noop logs on leader change will trigger the whole
log replication procedure that ends up committing/applying state deltas on newly
elected leaders that didn't receive the last commit index from the previous
leader.
I also included a small tweak that won't trigger add logs when a transaction
contains only BEGIN and ABORT StateDeltas, because we don't want to replicate
read queries.
Reviewers: ipaljak
Reviewed By: ipaljak
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1785
