sim_fabric/
source_sink_builder.rs

1// Copyright (c) 2025 Graphcore Ltd. All rights reserved.
2
3//! Library functions to build parts of the sim-fabric application.
4
5use std::rc::Rc;
6
7use gwr_components::sink::Sink;
8use gwr_components::source::Source;
9use gwr_engine::engine::Engine;
10use gwr_models::data_frame::DataFrame;
11use gwr_models::fabric::FabricConfig;
12use rand::SeedableRng;
13use rand::seq::SliceRandom;
14use rand_xoshiro::Xoshiro256PlusPlus;
15
16use crate::frame_gen::{FrameGen, TrafficPattern};
17
18// Define some types to aid readability
19pub type Sources = Vec<Rc<Source<DataFrame>>>;
20pub type Sinks = Vec<Rc<Sink<DataFrame>>>;
21
22#[expect(clippy::too_many_arguments)]
23#[must_use]
24pub fn build_source_sinks(
25    engine: &mut Engine,
26    config: &Rc<FabricConfig>,
27    traffic_pattern: TrafficPattern,
28    overhead_size_bytes: usize,
29    payload_size_bytes: usize,
30    num_send_frames: usize,
31    seed: u64,
32    num_active_sources: usize,
33) -> (Sources, Sinks, usize) {
34    let top = engine.top();
35
36    let num_ports = config.num_ports();
37    let mut total_expected_frames = 0;
38    let mut sources = Vec::with_capacity(num_ports);
39
40    let mut rng = Xoshiro256PlusPlus::seed_from_u64(seed);
41
42    // Create random set of sources that will be active
43    let mut all_port_indices: Vec<usize> = config.port_indices().clone();
44    all_port_indices.shuffle(&mut rng);
45    let active_port_indices: Vec<usize> = all_port_indices
46        .into_iter()
47        .take(num_active_sources)
48        .collect();
49
50    // Create an random set of initial assigments
51    let mut dest_indices: Vec<usize> = config.port_indices().clone();
52    dest_indices.shuffle(&mut rng);
53
54    let first_dest = dest_indices[0];
55
56    for (i, dest_index) in dest_indices.drain(..).enumerate() {
57        let source_index = config.port_indices()[i];
58
59        let config = config.clone();
60        let initial_dest_index = if traffic_pattern == TrafficPattern::AllToOne {
61            first_dest
62        } else {
63            dest_index
64        };
65
66        let num_frames_from_source = if active_port_indices.contains(&source_index) {
67            match traffic_pattern {
68                // These generators won't send anything
69                TrafficPattern::AllToOne | TrafficPattern::AllToAllFixed => {
70                    if source_index == initial_dest_index {
71                        0
72                    } else {
73                        num_send_frames
74                    }
75                }
76                // All other generators will send the requested number without sending to self.
77                _ => num_send_frames,
78            }
79        } else {
80            0
81        };
82
83        total_expected_frames += num_frames_from_source;
84
85        let data_generator: std::option::Option<Box<dyn Iterator<Item = DataFrame>>> =
86            if active_port_indices.contains(&source_index) {
87                Some(Box::new(FrameGen::new(
88                    top,
89                    config,
90                    source_index,
91                    initial_dest_index,
92                    traffic_pattern,
93                    overhead_size_bytes,
94                    payload_size_bytes,
95                    num_send_frames,
96                    seed,
97                )))
98            } else {
99                None
100            };
101        sources.push(
102            Source::new_and_register(
103                engine,
104                top,
105                format!("source{source_index}").as_str(),
106                data_generator,
107            )
108            .unwrap(),
109        );
110    }
111
112    let sinks: Sinks = config
113        .port_indices()
114        .iter()
115        .map(|i| Sink::new_and_register(engine, top, format!("sink{i}").as_str()).unwrap())
116        .collect();
117
118    (sources, sinks, total_expected_frames)
119}
sim_fabric/source_sink_builder.rs

sim_fabric/
source_sink_builder.rs
