core: change the margin type used for scheduled point in core

OpenRailAssociation / osrd

An open source web application for railway infrastructure design, capacity analysis, timetabling and simulation

https://osrd.fr

GNU Lesser General Public License v3.0

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core: change the margin type used for scheduled point in core #6322

Open Castavo opened 6 months ago

Castavo commented 6 months ago

Description and goal

Today we use mareco, which is slow, we want to use linear to improve computation speed. (Ideally this could be a parameter)

Acceptance criteria

[ ] The scheduled points use the linear margin type
[ ] POST timetable/{id} have a parameter margin_type (or other name) to specify which one must be used

bloussou commented 6 months ago

Having a parameter will be possible with train schedule v2, adding this to the endpoint POST /timetable/{id} v1 could be nice too just to compare performances and be able to benchmark. It will be lost work but if it is not too much work then we should do it in my opinion.

Castavo commented 5 months ago

We tried it, and the number of trains working decreased (some trains work only with MARECO, some with Linear, but more work with MARECO apparently).

We still saw an average decrease of import time of 8% for the ones who worked.

We chose to not investigate further, for now, as the reason why these algorithm differ might be very hard to find.