Summary:
It seems that older clang versions erroneously accept modification of
constant pointers, this is a quick hack which resolves the issue on new
clang versions.
None of the const methods are really const and should not be marked as
such. This whole accessor thing is just a steaming pile of crap and
should be rewritten from scratch.
Reviewers: vkasljevic, msantl
Reviewed By: vkasljevic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1922
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:
`EdgesIterable` is used for iterating over Edges in distributed memgraph. Because of lru cache there is a possibility of data getting evicted as someone iterates over it.
To prevent that `EdgesIterable` will lock that data and release it when it's deconstructed.
Reviewers: msantl
Reviewed By: msantl
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1868
Summary:
CachedDataLock is necessary for lru cache as remote data is no longer
persistent. Most methods internally handle this, but for methods that
return pointers or references to remote data, we need to manually
lock data.
Reviewers: msantl, ipaljak
Reviewed By: msantl
Subscribers: teon.banek, pullbot
Differential Revision: https://phabricator.memgraph.io/D1869
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:
RecordAccessor doesn't implement `operator<`, so it doesn't make sense
to have it inherit TotalOrdering.
Reviewers: mferencevic, msantl, vkasljevic
Reviewed By: vkasljevic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1866
Summary:
`Edges` class didn't properly filter edges when given both edge type
and destination arguments, which causes weird bugs in query execution (wrong
edge getting matched in `Expand` with existing node flag set). This is probably
because we didn't support using both filters at the same time, but the API and
documentation for `VertexAccessor::in` and `VertexAccessor::out` functions
didn't reflect that.
Reviewers: teon.banek, msantl
Reviewed By: msantl
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1796
Summary:
This is just the first diff that tries to wire the raft protocol into
memgraph.
In this diff I'm introducing transaction engine reset functionality. I also
introduced `RaftInterface` which should be used wherever someone wants to access
Raft from Memgraph.
For design decisions see the feature spec.
Reviewers: ipaljak, teon.banek
Reviewed By: ipaljak
Subscribers: pullbot, teon.banek
Differential Revision: https://phabricator.memgraph.io/D1758
Summary:
GraphDb now has GetStorageStat method that returns live view to
object containing vertex_count, edge_count and avg_degree().
Stat is updated on each garbage collection run and represents number of
objects that are visible to any transaction.
Reviewers: teon.banek, msantl, ipaljak
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1731
Summary:
Since we need to send `StateDelta`s over the wire in HA, we need to be
able to serialize those bad boys.
This diff hopefully does this the right way.
Reviewers: teon.banek, mferencevic, ipaljak
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1725
Summary:
Initial for fork (in form of a c/p) form the current single node
version. Once we finish HA we plan to re-link the files to the single node
versions if they don't change.
Reviewers: ipaljak, buda, mferencevic
Reviewed By: ipaljak
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1705
Summary:
Blocking transaction has the ability to stop the transaction engine from
starting new transactions (regular or blocking) and to wait all other active
transactions to finish (to become non active, committed or aborted). One thing
that blocking transactions support is defining the parent transaction which
does not need to end in order for the blocking one to start. This is because of
a use case where we start nested transactions.
One could thing we should build indexes inside those blocking transactions. This
is true and I wanted to implement this, but this would require some digging in
the interpreter which I didn't want to do in this change.
Reviewers: mferencevic, vkasljevic, teon.banek
Reviewed By: mferencevic, teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1695
Summary:
LabelPropertyIndex now has the ability to enforce unique constraint.
This doesn't lock the tx engine.
Reviewers: teon.banek, mferencevic
Reviewed By: teon.banek
Subscribers: pullbot, vkasljevic, buda
Differential Revision: https://phabricator.memgraph.io/D1660
Summary:
This diff fixes the storage part of the bug that happen for the
following queries if all nodes end up on the non-master machine.
```
CREATE (a:T{c: True})-[:X{x: 2.5}]->(:A:B)-[:Y]->()-[:Z{r: 1}]->(a)
MATCH (:T{c: True})-[a:X{x: 2.5}]->(node:A:B)-[:Y]->()-[:Z{r: 1}]->() RETURN a AS node, node AS a
```
The current state of the code doesn't work completely, it's still missing the
query execution fix.
Reviewers: teon.banek, ipaljak, vkasljevic
Reviewed By: teon.banek
Subscribers: mferencevic, pullbot
Differential Revision: https://phabricator.memgraph.io/D1629
Summary:
Start removing `is_remote` from `Address`
Remove `GlobalAddress`
Remove `GlobalizedAddress`
Remove bitmasks from `Address`
Remove `is_local` from `Address`
Remove `is_local` from `RecordAccessor`
Remove `worker_id` from `Address`
Remove `worker_id` from `GidGenerator`
Unfriend `IndexRpcServer` from `Storage`
Remove `LocalizedAddressIfPossible`
Make member private
Remove `worker_id` from `Storage`
Copy function to ease removal of distributed logic
Remove `worker_id` from `WriteAheadLog`
Remove `worker_id` from `GraphDb`
Remove `worker_id` from durability
Remove nonexistant function
Remove `gid` from `Address`
Remove usage of `Address`
Remove `Address`
Remove `VertexAddress` and `EdgeAddress`
Fix Id test
Remove `cypher_id` from `VersionList`
Remove `cypher_id` from durability
Remove `cypher_id` member from `VersionList`
Remove `cypher_id` from database
Fix recovery (revert D1142)
Remove unnecessary functions from `GraphDbAccessor`
Revert `InsertEdge` implementation to the way it was in/before D1142
Remove leftover `VertexAddress` from `Edge`
Remove `PostCreateIndex` and `PopulateIndexFromBuildIndex`
Split durability paths into single node and distributed
Fix `TransactionIdFromWalFilename` implementation
Fix tests
Remove `cypher_id` from `snapshooter` and `durability` test
Reviewers: msantl, teon.banek
Reviewed By: msantl
Subscribers: msantl, pullbot
Differential Revision: https://phabricator.memgraph.io/D1647
Summary:
`heaptrack` shows a miniscule decrease in memory usage during query
execution.
Running the below query on the TEDTalk database 100 times gives the
following results:
- number of allocations: from 642647 to 642589
- bytes allocated in total: from 48.79 MiB to 48.78 MiB
```
MATCH (t:Tag)<-[:HasTag]-(n:Talk)
RETURN t.name AS Tag, COUNT(n) AS TalksCount
ORDER BY TalksCount DESC, Tag LIMIT 20;
```
Regarding `TypedValue`'s destructor: we're allowed to manually destruct the
union memebers that we constructed using placement-new. However, it is undefined
behavior to call the destructor after an object's lifetime has ended. Calling
`TypedValue`'s own destructor within its assignment operator counts as ending
its lifetime, which means that the next call to its destructor will invoke
undefined behavior.
See the C++ Draft N4140, clauses 12.4/15 and 3.8/1.3.
Reviewers: teon.banek, mtomic
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1630
Summary:
To clean the working directory after this diff you should execute:
```
rm src/database/counters_rpc_messages.capnp
rm src/database/counters_rpc_messages.hpp
rm src/database/serialization.capnp
rm src/database/serialization.hpp
```
Reviewers: teon.banek, msantl
Reviewed By: msantl
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1636
Summary:
This diff splits single node and distributed storage from each other.
Currently all of the storage code is copied into two directories (one single
node, one distributed). The logic used in the storage implementation isn't
touched, it will be refactored in following diffs.
To clean the working directory after this diff you should execute:
```
rm database/state_delta.capnp
rm database/state_delta.hpp
rm storage/concurrent_id_mapper_rpc_messages.capnp
rm storage/concurrent_id_mapper_rpc_messages.hpp
```
Reviewers: teon.banek, buda, msantl
Reviewed By: teon.banek, msantl
Subscribers: teon.banek, pullbot
Differential Revision: https://phabricator.memgraph.io/D1625
Summary:
This should allow us to more easily decouple the code which should be
open sourced. Unfortunately, the downside of this approach is that we
cannot rely on virtual calls to dispatch the serialization to correct
type. Another downside is that members need to be publicly accessible
for serialization.
Reviewers: mtomic, msantl
Reviewed By: mtomic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1596
Summary:
This diff changes the RPC layer to directly return `TResponse` to the user when
issuing a `Call<...>` RPC call. The call throws an exception on failure
(instead of the previous return `nullopt`).
All servers (network, RPC and distributed) are set to have explicit `Shutdown`
methods so that a controlled shutdown can always be performed. The object
destructors now have `CHECK`s to enforce that the `AwaitShutdown` methods were
called.
The distributed memgraph is changed that none of the binaries (master/workers)
crash when there is a communication failure. Instead, the whole cluster starts
a graceful shutdown when a persistent communication error is detected.
Transient errors are allowed during execution. The transaction that errored out
will be aborted on the whole cluster. The cluster state is managed using a new
Heartbeat RPC call.
Reviewers: buda, teon.banek, msantl
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1604
Summary:
Previous version of code was wrong in some cases. Example:
There's an edge e = (a)->(b). Node (a) belongs to worker 1, node (b) belongs to worker 0. Therefore, edge e belongs to worker 1.
When edge e was serialized on worker 0, address of node b was local and it would be globalized, but the worker id of edge (e) would be used, which is wrong.
Reviewers: teon.banek
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1599
Summary:
In a bunch of places `TypedValue` was used where `PropertyValue` should be. A lot of times it was only because `TypedValue` serialization code could be reused for `PropertyValue`, only without providing callbacks for `VERTEX`, `EDGE` and `PATH`. So first I wrote separate serialization code for `PropertyValue` and put it into storage folder. Then I fixed all the places where `TypedValue` was incorrectly used instead of `PropertyValue`. I also disabled implicit `TypedValue` to `PropertyValue` conversion in hopes of preventing misuse in the future.
After that, I wrote code for `VertexAccessor` and `EdgeAccessor` serialization and put it into `storage` folder because it was almost duplicated in distributed BFS and pull produce RPC messages. On the sender side, some subset of records (old or new or both) is serialized, and on the reciever side, records are deserialized and immediately put into transaction cache.
Then I rewrote the `TypedValue` serialization functions (`SaveCapnpTypedValue` and `LoadCapnpTypedValue`) to not take callbacks for `VERTEX`, `EDGE` and `PATH`, but use accessor serialization functions instead. That means that any code that wants to use `TypedValue` serialization must hold a reference to `GraphDbAccessor` and `DataManager`, so that should make clients reconsider if they really want to use `TypedValue` instead of `PropertyValue`.
Reviewers: teon.banek, msantl
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1598
Summary:
Since RecordAccessor is often instantiated and copied, using a
factory-like function to allocate concrete types on the heap would be
too costly. The approach in this diff uses a Strategy pattern (see
"Design Patterns" by Gamma et al.), where the Strategy interface is
given as RecordAccessor::Impl. Concrete implementations are then created
for each GraphDb. This allows us to instantiate the concrete
RecordAccessors::Impl *once* and *share* it among all RecordAccessors.
Reviewers: msantl, vkasljevic
Reviewed By: msantl
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1510
Summary:
Since we switched to Cap'n Proto serialization there's no need for
keeping boost around anymore.
Reviewers: mtomic, mferencevic, buda
Reviewed By: mtomic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D1515
