via search is extremely slow

[miklcct]

Expected behavior

A search with one via point takes at most twice the time of the search without via point.

Observed behavior

It takes much more time compared to a search without via point.

The following query took 3 minutes and 22 seconds to run, but without the via point, it only took 9 seconds. Caching isn't an issue as I ran the query without the via point first, then with via point afterwards.

Version of OTP used (exact commit hash or JAR name)

2.7.0-SNAPSHOT

Data sets in use (links to GTFS and OSM PBF files)

Great Britain OSM + GTFS

Command line used to start OTP

Router config and graph build config JSON

Steps to reproduce the problem

1. Plan a journey with a via point, with the following query

# This is an example query for fetching all routes of your OTP deployment.
# Click on the documentation icon on the left to read about the available types
# or use autocomplete to explore the schema.
query GtfsExampleQuery {
  planConnection(
    origin: {
      location: {
        coordinate: {
          latitude: 51.5
          longitude: 0.0
        }
      }
    }
    destination: {
      location: {
        coordinate: {
          latitude: 51.50743
          longitude: -0.12772
        }
      }
    }
    via: [
      {
      	visit: {
          stopLocationIds: ["GB:910GLNDNBDE"]
          minimumWaitTime: "PT30M"
      	}
      }
    ]
  ) {
    edges {
      node {
        start
        end
        legs {
          from {
            name
          }
          to {
            name
          }
          route {
            shortName
          }
        }
      }
    }
  }
}

[t2gran]

If you query the two segments separately, what do you get?

• From (51.5, 0.0) to "GB:910GLNDNBDE"
• From "GB:910GLNDNBDE" to (51.50743, -0.12772)

[miklcct]

They are fast, with response time just 4 and 6 seconds respectively.

[miklcct]

The same problem also appears at the production Digitransit all-Finland server ( https://api.digitransit.fi/routing/v2/finland/gtfs/v1 ) - the query timed out after about 30 seconds. Without a via point, it only takes 5 seconds for results to load.

However, the response time from the Norway test server ( https://otp2debug.entur.org/otp/routers/default/index/graphql ) is normal.