Commit Graph

5 Commits

Author SHA1 Message Date
Teon Banek
8da3839a1d Convert variable start planning to iterative process
Summary: This change increases the planning time, but should reduce memory consumption.

Reviewers: florijan, mislav.bradac

Reviewed By: mislav.bradac

Subscribers: pullbot

Differential Revision: https://phabricator.memgraph.io/D901
2017-10-16 10:12:09 +02:00
florijan
76fe8bfadf Variable expansion consolidaton
Summary:
- Removed BreadthFirstAtom, using EdgeAtom only with a Type enum.
- Both variable expansions (breadth and depth first) now have mandatory inner node and edge Identifiers.
- Both variable expansions use inline property filtering and support inline lambdas.
- BFS and variable expansion now have the same planning process.
- Planner modified in the following ways:
	- Variable expansions support inline property filtering (two filters added to all_filters, one for inline, one for post-expand).
	- Asserting against existing_edge since we don't support that anymore.
	- Edge and node symbols bound after variable expansion to disallow post-expand filters to get inlined.
	- Some things simplified due to different handling.
- BreadthFirstExpand logical operator merged into ExpandVariable. Two Cursor classes remain and are dynamically chosen from.

As part of planned planner refactor we should ensure that a filter is applied only once. The current implementation is very suboptimal for property filtering in variable expansions.

@buda: we will start refactoring this these days. This current planner logic is too dense and complex. It is becoming technical debt. Most of the time I spent working on this has been spent figuring the planning out, and I still needed Teon's help at times. Implementing the correct and optimal version of query execution (avoiding multiple potentially expensive filterings) was out of reach also due to tech debt.

Reviewers: buda, teon.banek

Reviewed By: teon.banek

Subscribers: pullbot, buda

Differential Revision: https://phabricator.memgraph.io/D852
2017-10-05 13:12:39 +02:00
Teon Banek
b31478dfd8 Look into parameter value when estimating plan cost
Summary: Test cost estimator considers parameter values

Reviewers: florijan, mislav.bradac

Reviewed By: florijan

Subscribers: pullbot

Differential Revision: https://phabricator.memgraph.io/D798
2017-09-15 16:14:57 +02:00
Teon Banek
0aee18544d Add caching VerticesCount during planning and estimation
Summary:
Benchmark planning and estimating indexed ScanAll. According to the benchmark,
caching speeds up the whole process of planning and estimation by a factor of
2. Most of the performance gain is in the `CostEstimator` itself, due to plenty
of calls to `VerticesCount` when estimating all of the generated plans.

Reviewers: mislav.bradac, florijan

Reviewed By: mislav.bradac

Subscribers: pullbot

Differential Revision: https://phabricator.memgraph.io/D765
2017-09-09 12:26:48 +02:00
Teon Banek
591d086013 Map symbols to expansions to speed up variable planning
Summary:
Test variable planning BFS.
Add more tests for variably planning ExpandVariable.
Don't recreate the whole matching when varying expansions.
Use explicit constructors in private planner classes.

Reviewers: mislav.bradac, florijan

Reviewed By: mislav.bradac

Subscribers: pullbot

Differential Revision: https://phabricator.memgraph.io/D691
2017-08-23 11:39:45 +02:00