faster

Cargo.lock

@@ -2,6 +2,18 @@
 # It is not intended for manual editing.
 version = 4
 
+[[package]]
+name = "autocfg"
+version = "1.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ace50bade8e6234aa140d9a2f552bbee1db4d353f69b8217bc503490fc1a9f26"
+
+[[package]]
+name = "bitflags"
+version = "2.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8f68f53c83ab957f72c32642f3868eec03eb974d1fb82e453128456482613d36"
+
 [[package]]
 name = "byteorder"
 version = "1.5.0"
@@ -18,16 +30,71 @@ checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 name = "chains-gen"
 version = "0.1.0"
 dependencies = [
+ "dashmap",
+ "fnv",
  "indexmap",
  "rand",
+ "rayon",
 ]
 
+[[package]]
+name = "crossbeam-deque"
+version = "0.8.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9dd111b7b7f7d55b72c0a6ae361660ee5853c9af73f70c3c2ef6858b950e2e51"
+dependencies = [
+ "crossbeam-epoch",
+ "crossbeam-utils",
+]
+
+[[package]]
+name = "crossbeam-epoch"
+version = "0.9.18"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5b82ac4a3c2ca9c3460964f020e1402edd5753411d7737aa39c3714ad1b5420e"
+dependencies = [
+ "crossbeam-utils",
+]
+
+[[package]]
+name = "crossbeam-utils"
+version = "0.8.21"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d0a5c400df2834b80a4c3327b3aad3a4c4cd4de0629063962b03235697506a28"
+
+[[package]]
+name = "dashmap"
+version = "6.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5041cc499144891f3790297212f32a74fb938e5136a14943f338ef9e0ae276cf"
+dependencies = [
+ "cfg-if",
+ "crossbeam-utils",
+ "hashbrown 0.14.5",
+ "lock_api",
+ "once_cell",
+ "parking_lot_core",
+ "rayon",
+]
+
+[[package]]
+name = "either"
+version = "1.13.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "60b1af1c220855b6ceac025d3f6ecdd2b7c4894bfe9cd9bda4fbb4bc7c0d4cf0"
+
 [[package]]
 name = "equivalent"
 version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5443807d6dff69373d433ab9ef5378ad8df50ca6298caf15de6e52e24aaf54d5"
 
+[[package]]
+name = "fnv"
+version = "1.0.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3f9eec918d3f24069decb9af1554cad7c880e2da24a9afd88aca000531ab82c1"
+
 [[package]]
 name = "getrandom"
 version = "0.2.15"
@@ -39,6 +106,12 @@ dependencies = [
  "wasi",
 ]
 
+[[package]]
+name = "hashbrown"
+version = "0.14.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e5274423e17b7c9fc20b6e7e208532f9b19825d82dfd615708b70edd83df41f1"
+
 [[package]]
 name = "hashbrown"
 version = "0.15.2"
@@ -52,7 +125,8 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8c9c992b02b5b4c94ea26e32fe5bccb7aa7d9f390ab5c1221ff895bc7ea8b652"
 dependencies = [
  "equivalent",
- "hashbrown",
+ "hashbrown 0.15.2",
+ "rayon",
 ]
 
 [[package]]
@@ -61,6 +135,35 @@ version = "0.2.169"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b5aba8db14291edd000dfcc4d620c7ebfb122c613afb886ca8803fa4e128a20a"
 
+[[package]]
+name = "lock_api"
+version = "0.4.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "07af8b9cdd281b7915f413fa73f29ebd5d55d0d3f0155584dade1ff18cea1b17"
+dependencies = [
+ "autocfg",
+ "scopeguard",
+]
+
+[[package]]
+name = "once_cell"
+version = "1.20.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1261fe7e33c73b354eab43b1273a57c8f967d0391e80353e51f764ac02cf6775"
+
+[[package]]
+name = "parking_lot_core"
+version = "0.9.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1e401f977ab385c9e4e3ab30627d6f26d00e2c73eef317493c4ec6d468726cf8"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "redox_syscall",
+ "smallvec",
+ "windows-targets",
+]
+
 [[package]]
 name = "ppv-lite86"
 version = "0.2.20"
@@ -118,6 +221,47 @@ dependencies = [
  "getrandom",
 ]
 
+[[package]]
+name = "rayon"
+version = "1.10.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b418a60154510ca1a002a752ca9714984e21e4241e804d32555251faf8b78ffa"
+dependencies = [
+ "either",
+ "rayon-core",
+]
+
+[[package]]
+name = "rayon-core"
+version = "1.12.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1465873a3dfdaa8ae7cb14b4383657caab0b3e8a0aa9ae8e04b044854c8dfce2"
+dependencies = [
+ "crossbeam-deque",
+ "crossbeam-utils",
+]
+
+[[package]]
+name = "redox_syscall"
+version = "0.5.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "03a862b389f93e68874fbf580b9de08dd02facb9a788ebadaf4a3fd33cf58834"
+dependencies = [
+ "bitflags",
+]
+
+[[package]]
+name = "scopeguard"
+version = "1.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "94143f37725109f92c262ed2cf5e59bce7498c01bcc1502d7b9afe439a4e9f49"
+
+[[package]]
+name = "smallvec"
+version = "1.13.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3c5e1a9a646d36c3599cd173a41282daf47c44583ad367b8e6837255952e5c67"
+
 [[package]]
 name = "syn"
 version = "2.0.96"
@@ -141,6 +285,70 @@ version = "0.11.0+wasi-snapshot-preview1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9c8d87e72b64a3b4db28d11ce29237c246188f4f51057d65a7eab63b7987e423"
 
+[[package]]
+name = "windows-targets"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9b724f72796e036ab90c1021d4780d4d3d648aca59e491e6b98e725b84e99973"
+dependencies = [
+ "windows_aarch64_gnullvm",
+ "windows_aarch64_msvc",
+ "windows_i686_gnu",
+ "windows_i686_gnullvm",
+ "windows_i686_msvc",
+ "windows_x86_64_gnu",
+ "windows_x86_64_gnullvm",
+ "windows_x86_64_msvc",
+]
+
+[[package]]
+name = "windows_aarch64_gnullvm"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "32a4622180e7a0ec044bb555404c800bc9fd9ec262ec147edd5989ccd0c02cd3"
+
+[[package]]
+name = "windows_aarch64_msvc"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "09ec2a7bb152e2252b53fa7803150007879548bc709c039df7627cabbd05d469"
+
+[[package]]
+name = "windows_i686_gnu"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8e9b5ad5ab802e97eb8e295ac6720e509ee4c243f69d781394014ebfe8bbfa0b"
+
+[[package]]
+name = "windows_i686_gnullvm"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0eee52d38c090b3caa76c563b86c3a4bd71ef1a819287c19d586d7334ae8ed66"
+
+[[package]]
+name = "windows_i686_msvc"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "240948bc05c5e7c6dabba28bf89d89ffce3e303022809e73deaefe4f6ec56c66"
+
+[[package]]
+name = "windows_x86_64_gnu"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "147a5c80aabfbf0c7d901cb5895d1de30ef2907eb21fbbab29ca94c5b08b1a78"
+
+[[package]]
+name = "windows_x86_64_gnullvm"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "24d5b23dc417412679681396f2b49f3de8c1473deb516bd34410872eff51ed0d"
+
+[[package]]
+name = "windows_x86_64_msvc"
+version = "0.52.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "589f6da84c646204747d1270a2a5661ea66ed1cced2631d546fdfb155959f9ec"
+
 [[package]]
 name = "zerocopy"
 version = "0.7.35"

Cargo.toml

@@ -4,5 +4,8 @@ version = "0.1.0"
 edition = "2024"
 
 [dependencies]
-indexmap = "2.7.0"
+dashmap = { version = "6.1.0", features = ["rayon"] }
+fnv = "1.0.7"
+indexmap = { version = "2.7.0", features = ["rayon"] }
 rand = "0.8.5"
+rayon = "1.10.0"

src/main.rs

@@ -2,20 +2,21 @@ use std::time::Instant;
 
 use markov::{MarkovAllNodes, MarkovNode, MarkovToken};
 
+use rayon::{iter::ParallelIterator, str::ParallelString};
+
 mod markov;
 
 fn main() {
     // chain creation
 
     let content = std::fs::read_to_string("./data.txt").unwrap();
-    let lines = content.lines();
 
-    let mut all_nodes = MarkovAllNodes::new();
+    let all_nodes = MarkovAllNodes::new();
     let root_node = MarkovNode::new(MarkovToken::Root);
     let end_node = MarkovNode::new(MarkovToken::End);
 
     let start = Instant::now();
-    for line in lines {
+    content.par_lines().for_each(|line| {
         let mut nodes = line
             .split_whitespace()
             .filter(|s| s.chars().all(|c| c.is_ascii_alphanumeric()))
@@ -30,13 +31,20 @@ fn main() {
                 break;
             }
 
-            node.conns.borrow_mut().connect(next_node.clone());
+            node.conns.connect(next_node.clone());
 
             node = next_node;
         }
-    }
+    });
     println!("took {:?} to create chain", start.elapsed());
 
+    // cache index maps
+
+    let start = Instant::now();
+    root_node.conns.index_map();
+    all_nodes.cache_index_maps();
+    println!("took {:?} to cache index maps", start.elapsed());
+
     // generation
 
     let mut rng = rand::thread_rng();
@@ -52,7 +60,7 @@ fn main() {
             .unwrap_or_else(|| root_node.clone());
 
         loop {
-            let next_node = node.conns.borrow().random_weighted(&mut rng);
+            let next_node = node.conns.random_weighted(&mut rng);
 
             if let MarkovToken::Value(value) = &node.value {
                 result += value;

src/markov.rs

@@ -1,8 +1,13 @@
-use std::{cell::RefCell, collections::HashMap, hash::Hash, rc::Rc};
+use std::{
+    hash::Hash,
+    sync::{Arc, OnceLock},
+};
 
-use indexmap::IndexMap;
 use rand::{distributions::WeightedIndex, prelude::Distribution, rngs::ThreadRng};
 
+type FnvDashMap<K, V> = dashmap::DashMap<K, V, fnv::FnvBuildHasher>;
+type FnvIndexMap<K, V> = indexmap::IndexMap<K, V, fnv::FnvBuildHasher>;
+
 #[derive(PartialEq, Eq, Hash, Debug)]
 pub enum MarkovToken {
     Root,
@@ -22,9 +27,14 @@ impl MarkovToken {
 
 pub struct MarkovNode {
     pub value: MarkovToken,
-    pub conns: RefCell<MarkovConns>,
+    pub conns: MarkovConns,
 }
 
+impl std::fmt::Debug for MarkovNode {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> Result<(), std::fmt::Error> {
+        self.value.fmt(f)
+    }
+}
 impl PartialEq for MarkovNode {
     fn eq(&self, other: &Self) -> bool {
         self.value.eq(&other.value)
@@ -38,55 +48,70 @@ impl Hash for MarkovNode {
 }
 
 impl MarkovNode {
-    pub fn new(token: MarkovToken) -> Rc<Self> {
+    pub fn new(token: MarkovToken) -> Arc<Self> {
-        Rc::new(Self {
+        let conns = MarkovConns {
+            conns: FnvDashMap::default(),
+            im_cached: OnceLock::new(),
+        };
+
+        Arc::new(Self {
             value: token,
-            conns: RefCell::new(MarkovConns(IndexMap::new())),
+            conns,
         })
     }
 }
 
-pub struct MarkovConns(pub IndexMap<Rc<MarkovNode>, u32>);
+pub struct MarkovConns {
+    conns: FnvDashMap<Arc<MarkovNode>, u32>,
+    im_cached: OnceLock<FnvIndexMap<Arc<MarkovNode>, u32>>,
+}
 
 impl MarkovConns {
-    pub fn connect(&mut self, word: Rc<MarkovNode>) {
+    pub fn connect(&self, n: Arc<MarkovNode>) {
-        if let Some(count) = self.0.get_mut(&word) {
+        self.conns.entry(n).and_modify(|c| *c += 1).or_insert(1);
-            *count += 1;
-        } else {
-            self.0.insert(word, 1);
-        }
     }
 
-    fn index(&self, i: usize) -> Rc<MarkovNode> {
+    pub fn index_map(&self) -> &FnvIndexMap<Arc<MarkovNode>, u32> {
-        self.0.get_index(i).map(|(n, _)| n.clone()).unwrap()
+        self.im_cached.get_or_init(|| {
+            self.conns
+                .iter()
+                .map(|r| (r.key().clone(), *r.value()))
+                .collect::<FnvIndexMap<_, _>>()
+        })
     }
 
-    pub fn random_weighted(&self, rng: &mut ThreadRng) -> Rc<MarkovNode> {
+    pub fn random_weighted(&self, rng: &mut ThreadRng) -> Arc<MarkovNode> {
-        let wi = WeightedIndex::new(self.0.iter().map(|(_, c)| c)).unwrap(); // SAFETY: there should always be at least an end token
+        let im = self.index_map();
+
+        let wi = WeightedIndex::new(im.iter().map(|(_, c)| c).copied()).unwrap(); // SAFETY: there should always be at least an end token
         let i = wi.sample(rng);
 
-        self.index(i)
+        im.get_index(i).map(|(n, _)| n.clone()).unwrap()
     }
 }
 
-pub struct MarkovAllNodes(HashMap<String, Rc<MarkovNode>>);
+pub struct MarkovAllNodes(FnvDashMap<String, Arc<MarkovNode>>);
 
 impl MarkovAllNodes {
     pub fn new() -> Self {
-        Self(HashMap::new())
+        Self(FnvDashMap::default())
     }
 
-    pub fn node(&mut self, word: &str) -> Rc<MarkovNode> {
+    pub fn node(&self, word: &str) -> Arc<MarkovNode> {
-        if let Some(node) = self.0.get(word) {
+        self.0
-            node.clone()
+            .entry(word.to_string())
-        } else {
+            .or_insert_with(|| MarkovNode::new(MarkovToken::Value(word.to_string())))
-            let node = MarkovNode::new(MarkovToken::Value(word.to_string()));
+            .value()
-            self.0.insert(word.to_string(), node.clone());
+            .clone()
-            node
-        }
     }
 
-    pub fn try_node(&self, word: &str) -> Option<Rc<MarkovNode>> {
+    pub fn try_node(&self, word: &str) -> Option<Arc<MarkovNode>> {
-        self.0.get(word).cloned()
+        self.0.get(word).map(|r| r.clone())
+    }
+
+    pub fn cache_index_maps(&self) {
+        self.0.iter().for_each(|e| {
+            e.value().conns.index_map();
+        });
     }
 }