Summary:
All mgp_* symbols are exported from Memgraph executable, no other
symbols should be visible.
The primary C API header, mg_procedure.h, is now part of the
installation. Also, added a shippable query module example.
Directory `query_modules` is meant to contain sources of modules we
write and ship as part of the installation. Currently, there's only an
example module, but there may be potentially more. Some modules could
only be installed as part of the enterprise release.
For Memgraph to load custom procedures, it needs to be started with a
flag pointing to a directory with compiled shared libraries implementing
those procedures.
Reviewers: mferencevic, ipaljak, llugovic, dsantl, buda
Reviewed By: mferencevic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2538
Summary:
This change increases the throughput of the storage v2 durability 20x. With
this change, the storage v2 durability is 3x faster than the storage v1
durability in both recovery and snapshotting (before the change v2 durability
is slower than v1 durability).
Reviewers: teon.banek
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2529
Summary:
Store accumulated results as `communication::bolt::Value`s instead of
`TypedValue`s.
Add additional overloads for `Result` and `Summary` which accept `TypedValue`s
but internally perform conversions.
Reviewers: teon.banek, mferencevic
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2514
Summary:
Depends on D2471
- Add pointer to storage to `InterpreterContext`
- Rename `operator()` to `Prepare`
- Use `Interpret` instead of `operator()` (`Interpret` will be removed soon)
- Remove the `in_explicit_transaction` parameter
- Remove the memory resource parameter from `Interpret`
- Remove the storage accessor parameter from `Interpret`
- Fix up tests (remove the `Interpreter` from `database_transaction_timeout`)
Reviewers: teon.banek, mferencevic
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2482
Summary: Make `InterpreterContext` a top level instead of a nested struct
Reviewers: teon.banek
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2512
Summary: For example, the aggregate element produced for `COUNT(*)` has its `value` set to `NULL`.
Reviewers: teon.banek
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2463
Summary:
The registry is now in the `query::procedure` namespace, this makes the
naming more consistent. I.e. we are dealing with custom procedure which
are contained in modules. This naming convention is similar to Python
source code where each file represents a module and each module provides
multiple functions (or procedures in our case). At the moment we only
support exactly 1 procedure per module, but the openCypher syntax allows
for more.
Reviewers: mferencevic, ipaljak, dsantl
Differential Revision: https://phabricator.memgraph.io/D2454
Summary:
This diff implements a mechanism for registering plugins which provide
custom procedures for openCypher. Although the `Plugin` struct already
stores some function pointers, these are not set in stone w.r.t. to
requirements and signatures.
For example, in the future, we may want to allow a single plugin to
register multiple custom procedures instead of just one.
Reviewers: ipaljak, dsantl, mferencevic
Reviewed By: mferencevic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2386
Summary:
This diff adds support for an auth module. The module is used to provide
authentication and authorization (only user to role mappings). The module can
be written in any language and uses a simple protocol to communicate with
Memgraph.
Reviewers: teon.banek, buda
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2359
Summary:
Switching to Storage V2 API will require passing storage::View when
serializing VertexAccessor and EdgeAccessor, so this is just the first
step in adapting the code.
Reviewers: mferencevic, ipaljak
Reviewed By: mferencevic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2352
Summary:
Most instances of `@throw std::bad_alloc` are left unexplained as these
functions perform general heap allocations are it's obvious from the
function name that it will do so. Basically anything with `Create`, `Make` or
`Build` implies allocations. Additionally, which parts exactly perform
allocations are an implementation detail. Functions which do unexpected
heap allocations have the reason stated in the documentation, these
functions typically have exactly one spot which could raise such an
exception.
Some functions are marked as `noexcept`, these are usually "special
functions" such as constructors and operators. This could potentially
improve performance because STL may use API overloads that work faster
with `noexcept` stuff. Remaining non-throwing functions aren't marked as
`noexcept` as that wasn't our practice nor is common in our codebase. On
the other hand, if we continue enforcing the documentation of thrown
exceptions, perhaps we should start using `noexcept`.
Reviewers: mferencevic, ipaljak
Reviewed By: mferencevic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2350
Summary:
This makes Gid the same as the one in storage/v2. Before they can be
merge into one implementation, we probably want to have a similar
transition for remaining ID types.
Depends on D2346
Reviewers: mferencevic, ipaljak
Reviewed By: mferencevic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2347
Summary:
It never made sense that a global ID is its own namespace in the storage
directory tree.
Reviewers: mferencevic, ipaljak
Reviewed By: mferencevic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2346
Summary:
This effectively replaces the old PropertyValue implementation from the
one in storage/v2
Depends on D2333
Reviewers: mferencevic, ipaljak
Reviewed By: mferencevic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2335
Summary:
This is a different scheme for setting up a bookkeeping object while
still supporting arbitrary allocation alignment requests. The previous
scheme was simpler as it always allocated a power of 2 bytes, but the
trade-off was increased memory usage. This should waste less memory.
Reviewers: mtomic, mferencevic, ipaljak
Reviewed By: mtomic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2321
Summary:
There's a possible race condition where we add a deleted vertex into
index and garbage collection removes it from main storage before indices are
cleaned-up.
Reviewers: mferencevic, teon.banek
Reviewed By: mferencevic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2314
Summary:
Utils now contain a BasicResult implementation which supports different
types of error. This will make it useful for other parts of the code as
well as during the transition from old to new storage.
Reviewers: mtomic, msantl, mferencevic
Reviewed By: mferencevic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2291
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:
This ought to simplify the code which needs to work with any kind of
vertex iteration, be it through an index store or regular.
Reviewers: mtomic, mferencevic
Reviewed By: mferencevic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2258
Summary: this will make GC for indices easier
Reviewers: teon.banek, mferencevic
Reviewed By: teon.banek, mferencevic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2223
Summary:
`std::unordered_map` is 56 bytes in size, `std::map` is 48 bytes in size.
Also, `std::map` doesn't require the key type to be hashable.
Reviewers: mtomic, teon.banek
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2218
Summary:
For proper client interaction, we need to expose the (term_id, log_index)
pair for the transaction that's about to be replicated and we need to be able
to retrieve the status of a transaction defined by that pair. Transaction
status can be one of the following:
1) REPLICATED (self-explanatory)
2) WAITING (waiting for replication)
3) ABORTED (self-explanatory)
4) INVALID (received request with either invalid term_id or invalid log_index)
Reviewers: mferencevic
Reviewed By: mferencevic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2201
Summary:
The first 2 tuple elements are redundant as they are available through
EdgeAccessor and they needlessly complicate the usage of the API.
Reviewers: mtomic, mferencevic
Reviewed By: mtomic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2200
Summary:
The newly added methods are modeled after the ones being added in C++20 to
`std::pmr::polymorphic_allocator`.
Reviewers: mtomic, mferencevic
Reviewed By: mferencevic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2197
Summary:
`lock_guard` is holding vertex lock while we're deleting the vertex,
and then it might try to unlock it in its destructor and access freed memory.
Reviewers: teon.banek, mferencevic
Reviewed By: mferencevic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2192
Summary:
This is a preparation step in case we want to have a custom allocator in
SkipList. For example, pool based allocator for SkipListNode.
Introduction of MemoryResource and removal of `calloc` has reduced the
performance a bit according to micro benchmarks. This performance hit is
not visible on benchmarks which do more concurrent operations.
Reviewers: mferencevic, mtomic
Reviewed By: mferencevic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2140
Summary:
This change implements full edges support in storage v2. Edges can be created
and deleted. Support for detach-deleting vertices is added and regular vertex
deletion verifies existance of edges.
Reviewers: mtomic, teon.banek
Reviewed By: mtomic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2180
Summary:
Instead of calling the wanted method, this diff takes copies of both `is_replicated(x)` and `is_active(x)` results so that they can't change during the method execution.
The problem with the previous implementation was that the information about a
log could change during two consecutive queries as ilustrated in the example
below.
```
Thread 1 Thread2
rlog->set_active(1);
if (rlog->is_replicated(1)) return true;
rlog->set_replicated(1);
if (rlog->is_active(1)) return false;
throw InvalidLogReplicationLookup();
```
The snippet above would throw as we don't have any information about the log
`1`, because the `set_replicated` call would "shadow" the active bit.
Reviewers: ipaljak
Reviewed By: ipaljak
Subscribers: pullbot, mferencevic
Differential Revision: https://phabricator.memgraph.io/D2165
Summary:
We forgot to update `modified_vertices` in the case when the vertex
has an empty version chain. It didn't manifest before because it was impossible
for a vertex to have an empty version chain without garbage collection.
Reviewers: mferencevic, teon.banek
Reviewed By: mferencevic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2154
Summary:
We forgot to add the newly created vertex into `modified_vertices`
list.
Reviewers: teon.banek, mferencevic
Reviewed By: mferencevic
Differential Revision: https://phabricator.memgraph.io/D2153
Summary:
Initial implementation of new storage engine. It implements snapshot isolation
for transactions. All changes in the database are stored as deltas instead of
making full copies. Currently, the storage supports full transaction
functionality (commit, abort, command advancement). Also, support has been
implemented only for vertices that have only labels.
Reviewers: teon.banek, mtomic
Reviewed By: teon.banek
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2138
Summary:
Micro benchmarks show some minor variations compared to the previous
commit. Smaller cases are a bit worse while larger data cases are a bit
better.
Reviewers: mtomic, mferencevic
Reviewed By: mtomic
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D2136
