From 35907dad8212eb85390d87531f3389d57011a650 Mon Sep 17 00:00:00 2001
From: Brian Hicks <brian@brianthicks.com>
Date: Tue, 24 Aug 2021 17:23:35 -0500
Subject: [PATCH] use a bump allocator again

---
 BENCHMARKING.md | 21 +++++++++++++++++++++
 Cargo.lock      | 38 ++++++++++++++++++++++++++++++++++++--
 Cargo.toml      |  3 ++-
 src/main.rs     |  4 ++++
 4 files changed, 63 insertions(+), 3 deletions(-)

diff --git a/BENCHMARKING.md b/BENCHMARKING.md
index c29baa5..308f225 100644
--- a/BENCHMARKING.md
+++ b/BENCHMARKING.md
@@ -170,3 +170,24 @@ Summary
 ```
 
 Yep!
+
+## Bump Allocation (again)
+
+Let's try the bump allocator again... it seemed like a fluke that it produced such a severe performance degradation.
+
+```
+$ hyperfine './result/bin/similar-sort define < /usr/share/dict/words' './target/release/similar-sort benchmark < /usr/share/dict/words'
+Benchmark #1: ./result/bin/similar-sort define < /usr/share/dict/words
+  Time (mean ± σ):     286.2 ms ±   5.0 ms    [User: 251.4 ms, System: 72.5 ms]
+  Range (min … max):   280.8 ms … 298.4 ms    10 runs
+
+Benchmark #2: ./target/release/similar-sort benchmark < /usr/share/dict/words
+  Time (mean ± σ):     111.3 ms ±   3.4 ms    [User: 94.7 ms, System: 16.0 ms]
+  Range (min … max):   104.1 ms … 118.5 ms    24 runs
+
+Summary
+  './target/release/similar-sort benchmark < /usr/share/dict/words' ran
+    2.57 ± 0.09 times faster than './result/bin/similar-sort define < /usr/share/dict/words'
+```
+
+That seems more like what I'd expect!
diff --git a/Cargo.lock b/Cargo.lock
index 13b4edb..e006877 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -21,7 +21,7 @@ version = "0.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ee49baf6cb617b853aa8d93bf420db2383fab46d314482ca2803b40d5fde979b"
 dependencies = [
- "winapi",
+ "winapi 0.3.9",
 ]
 
 [[package]]
@@ -32,7 +32,7 @@ checksum = "d9b39be18770d11421cdb1b9947a45dd3f37e93092cbf377614828a319d5fee8"
 dependencies = [
  "hermit-abi",
  "libc",
- "winapi",
+ "winapi 0.3.9",
 ]
 
 [[package]]
@@ -62,6 +62,17 @@ version = "1.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
 
+[[package]]
+name = "bump_alloc"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0272cee31aeb08593d1b75da4d942cb24ff6f4a08571a1d410aa7e7500ad8b37"
+dependencies = [
+ "kernel32-sys",
+ "libc",
+ "winapi 0.3.9",
+]
+
 [[package]]
 name = "cc"
 version = "1.0.69"
@@ -206,6 +217,16 @@ version = "0.3.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ce23b50ad8242c51a442f3ff322d56b02f08852c77e4c0b4d3fd684abc89c683"
 
+[[package]]
+name = "kernel32-sys"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7507624b29483431c0ba2d82aece8ca6cdba9382bff4ddd0f7490560c056098d"
+dependencies = [
+ "winapi 0.2.8",
+ "winapi-build",
+]
+
 [[package]]
 name = "lazy_static"
 version = "1.4.0"
@@ -372,6 +393,7 @@ dependencies = [
 name = "similar-sort"
 version = "2.0.0"
 dependencies = [
+ "bump_alloc",
  "color-eyre",
  "rayon",
  "strsim 0.10.0",
@@ -526,6 +548,12 @@ version = "0.9.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5fecdca9a5291cc2b8dcf7dc02453fee791a280f3743cb0905f8822ae463b3fe"
 
+[[package]]
+name = "winapi"
+version = "0.2.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "167dc9d6949a9b857f3451275e911c3f44255842c1f7a76f33c55103a909087a"
+
 [[package]]
 name = "winapi"
 version = "0.3.9"
@@ -536,6 +564,12 @@ dependencies = [
  "winapi-x86_64-pc-windows-gnu",
 ]
 
+[[package]]
+name = "winapi-build"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2d315eee3b34aca4797b2da6b13ed88266e6d612562a0c46390af8299fc699bc"
+
 [[package]]
 name = "winapi-i686-pc-windows-gnu"
 version = "0.4.0"
diff --git a/Cargo.toml b/Cargo.toml
index d91660b..2a3e86a 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -7,7 +7,8 @@ edition = "2018"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-structopt = "0.3.22"
+bump_alloc = "0.1.0"
 color-eyre = "0.5.7"
 rayon = "1.5.1"
 strsim = "0.10.0"
+structopt = "0.3.22"
diff --git a/src/main.rs b/src/main.rs
index 6490164..20e103c 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -4,6 +4,9 @@ use std::io::{self, stdin, stdout, BufRead, BufWriter, Write};
 use strsim::levenshtein;
 use structopt::StructOpt;
 
+#[global_allocator]
+static A: bump_alloc::BumpAlloc = bump_alloc::BumpAlloc::new();
+
 // works like `sort`, but sorts according to Levenshtein distance instead of
 // alphanumerically.
 #[derive(StructOpt)]
@@ -42,6 +45,7 @@ fn try_main() -> Result<()> {
     for (_, candidate) in distances {
         writeln!(out, "{}", candidate).context("could not write to stdout")?;
     }
+    out.flush().context("could not finish writing to stdout")?;
 
     Ok(())
 }