Try out faster hash algorithm

brood/Cargo.lock

@@ -41,6 +41,7 @@ name = "brood"
 version = "0.1.0"
 dependencies = [
  "clap",
+ "rustc-hash",
  "serde",
  "serde_json",
  "simd-json",
@@ -218,6 +219,12 @@ dependencies = [
  "proc-macro2",
 ]
 
+[[package]]
+name = "rustc-hash"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "08d43f7aa6b08d49f382cde6a7982047c3426db949b1424bc4b7ec9ae12c6ce2"
+
 [[package]]
 name = "ryu"
 version = "1.0.11"

brood/Cargo.toml

@@ -5,6 +5,7 @@ edition = "2021"
 
 [dependencies]
 clap = { version = "4.0.5", features = ["derive"] }
+rustc-hash = "1.1.0"
 serde = { version = "1.0.145", features = ["derive"] }
 serde_json = "1.0.85"
 simd-json = "0.6.0"

brood/src/ingest.rs

@@ -1,7 +1,7 @@
 use std::collections::hash_map::Entry;
-use std::collections::HashMap;
 use std::io::{self, BufRead, BufReader};
 
+use rustc_hash::FxHashMap;
 use serde::Deserialize;
 
 use crate::data::{Link, Page};
@@ -44,23 +44,23 @@ struct FirstStage {
     /// The first entry with id 0 represents a nonexistent link.
     pages: Vec<Page>,
     /// Map from title to index in [`Self::pages`] (used during the second pass).
-    pages_map: HashMap<String, u32>,
+    pages_map: FxHashMap<String, u32>,
     /// List with link info and index into [`Self::titles`].
     links: Vec<Link>,
     /// List with titles.
     titles: Vec<String>,
     /// Map from title to index in [`Self::titles`] (used during decoding).
-    titles_map: HashMap<String, u32>,
+    titles_map: FxHashMap<String, u32>,
 }
 
 impl FirstStage {
     fn new() -> Self {
         let mut result = Self {
             pages: vec![],
-            pages_map: HashMap::new(),
+            pages_map: FxHashMap::default(),
             links: vec![],
             titles: vec![],
-            titles_map: HashMap::new(),
+            titles_map: FxHashMap::default(),
         };
         result.push_page(0, 0, "this link does not exist".to_string(), false);
         result