v0.9.2: Performance

This version contains a performance improvement for the new nigiri core. The scale of the improvement depends on many factors such as dataset size or query type. To illustrate the differences between the different algorithms, a evaluation was done using a two week timetable of Germany, Switzerland and the Netherlands (each one as GTFS) and according OSM data.

In the follwing table Range 2h means that the departure time window was 2h, MCD is the multi-criteria Dijkstra contained in the routing module, TB is the TripBased algorithm. Nigiri is the new MOTIS core which is based on the RAPTOR algorithm. The coordinate to coordinate case considers up to 15 min walking for the first and last leg. Big differences can be seen on the 99% percentile where the slowest queries are now more than one second faster (or 35%).

Start	Query	Router	Avg.	q50	q80	q90	q99
Coordinate → Coordinate	Range 2h	MCD	2,321 ms	1,709 ms	3,647 ms	4,829 ms	10,131 ms
Coordinate → Coordinate	Range 2h	TB	1,952 ms	1,909 ms	2,742 ms	3,173 ms	4,416 ms
Coordinate → Coordinate	Range 2h	nigiri v0.9.1	1,049 ms	886 ms	1,561 ms	2,049 ms	3,530 ms
Coordinate → Coordinate	Range 2h	nigiri v0.9.2	802 ms	699 ms	1,157 ms	1,485 ms	2,303 ms

Differences for station to station queries are not as distinctive but especially the improvement on the 99% quantile is significant (10% reduction). EA query type stands for earliest arrival query (called Ontrip in the MOTIS API).

Start	Query	Router	Avg.	q50	q80	q90	q99
Station → Station	EA	MCD	555 ms	436 ms	745 ms	1,017 ms	2,002 ms
Station → Station	EA	TB	583 ms	465 ms	943 ms	1,230 ms	1,950 ms
Station → Station	EA	nigiri v0.9.1	209 ms	206 ms	290 ms	338 ms	428 ms
Station → Station	EA	nigiri v0.9.2	203 ms	202 ms	272 ms	311 ms	382 ms

Benchmarks were conducted on a AMD Ryzen 9 5900X 12-Core Processor with MOTIS built in Release mode. MOTIS calculations were limited to 12 threads.

Steps to reproduce

# config.ini

modules=nigiri
modules=intermodal
modules=osrm

mode=batch
num_threads=12
dataset.no_schedule=true
intermodal.router=nigiri
osrm.profiles=motis/osrm-profiles/foot.lua

[import]
paths=schedule-nl:input/schedule/nl
paths=schedule-delfi:input/schedule/delfi
paths=schedule-swiss:input/schedule/swiss
paths=osm:input/osm.pbf

[nigiri]
geo_lookup=true
first_day=2023-05-16
num_days=14

# config-routing.ini

modules=routing
modules=intermodal
modules=osrm
modules=lookup

mode=batch
num_threads=12
intermodal.router=routing
osrm.profiles=motis/osrm-profiles/foot.lua

[dataset]
begin=20230516
num_days=14
cache_graph=true
adjust_footpaths=false

[import]
paths=schedule-nl:input/schedule/nl
paths=schedule-delfi:input/schedule/delfi
paths=schedule-swiss:input/schedule/swiss
paths=osm:input/osm.pbf

# config-tripbased.ini

modules=routing
modules=intermodal
modules=osrm
modules=lookup
modules=tripbased

mode=batch
num_threads=12
intermodal.router=tripbased
osrm.profiles=motis/osrm-profiles/foot.lua

[dataset]
begin=20230516
num_days=14
cache_graph=true
adjust_footpaths=false

[import]
paths=schedule-nl:input/schedule/nl
paths=schedule-delfi:input/schedule/delfi
paths=schedule-swiss:input/schedule/swiss
paths=osm:input/osm.pbf

Generate coordinate to coordinate range queries (backward):

./motis/motis generate -c config-routing.ini --search_dir backward --start_type intermodal_pretrip --start_modes osrm_foot-15 --dest_type coordinate --dest_modes osrm_foot-15 --routers /routing /nigiri /tripbased --out q_ipretrip_idest_TARGET.txt

Generate station to station earliest arrival queries (forward):

./motis/motis generate -c config-routing.ini --message_type=routing --start_type=ontrip_station --dest_type=station --routers /routing /nigiri /tripbased --search_dir forward --out q_ontrip_sdest_TARGET.txt

Run routings:

~/code/motis/cmake-build-relwithdebinfo-mimalloc/motis -c config.ini --batch_input_file q_ipretrip_idest_nigiri.txt --batch_output_file r_ipretrip_idest_nigiri_new.txt && \
  ./motis/motis -c config.ini --batch_input_file q_ipretrip_idest_nigiri.txt --batch_output_file r_ipretrip_idest_nigiri_09.txt && \
  ./motis/motis -c config-routing.ini --batch_input_file q_ipretrip_idest_routing.txt --batch_output_file r_ipretrip_idest_routing.txt && \
  ./motis/motis -c config-tripbased.ini --batch_input_file q_ipretrip_idest_tripbased.txt --batch_output_file r_ipretrip_idest_tripbased.txt

Show statistics:

./motis/motis analyze r_ipretrip_idest_nigiri_new.txt && \
  ./motis/motis analyze r_ipretrip_idest_nigiri_09.txt && \
  ./motis/motis analyze r_ipretrip_idest_routing.txt && \
  ./motis/motis analyze r_ipretrip_idest_tripbased.txt

What's Changed

• Fixes for RI Basis + RSL RT by @pablohoch in #330
• nigiri gtfs loader memory improvement + routing speedup by @felixguendling in #331

Full Changelog: v0.9.1...v0.9.2