Benchmarks: lsf vs GNU ls

lsf v5.0.0 (Rust rewrite) vs GNU coreutils ls 9.10

Benchmarked with hyperfine using --shell=none (-N) for accurate sub-millisecond measurement. All tests run with --color=always to enable full ANSI color output on both tools.

System: Linux x86-64

Results Summary

lsf adds Nerd Font icons and colored icons to every entry -- GNU ls only adds filename colors. Despite this extra work, lsf matches or beats GNU ls in most scenarios.

Detailed Results

1. Small Directory - Grid View

Listing src/ (7 Rust source files):

Benchmark 1: /sbin/ls --color=always src/
  Time (mean +/- s):     745.8 us +/- 465.4 us
  Range (min ... max):   351.0 us ... 3375.1 us

Benchmark 2: ./target/release/lsf --color=always src/
  Time (mean +/- s):     649.2 us +/- 329.1 us
  Range (min ... max):   399.0 us ... 2437.5 us

Summary: lsf ran 1.15x faster than GNU ls

2. Large Directory - Grid View

Listing /tmp/lsf-bench/ (7300 files: 5000 .txt, 500 dirs, 1800 multi-extension):

Benchmark 1: /sbin/ls --color=always /tmp/lsf-bench/
  Time (mean +/- s):     10.2 ms +/- 3.6 ms
  Range (min ... max):    5.7 ms ... 22.8 ms

Benchmark 2: ./target/release/lsf --color=always /tmp/lsf-bench/
  Time (mean +/- s):     12.9 ms +/- 3.2 ms
  Range (min ... max):    8.5 ms ... 21.5 ms

Summary: GNU ls ran 1.27x faster than lsf

3. Long Format - Small Directory

-lah on src/ (7 files):

Benchmark 1: /sbin/ls -lah --color=always src/
  Time (mean +/- s):     1.7 ms +/- 1.0 ms

Benchmark 2: ./target/release/lsf -lah --color=always src/
  Time (mean +/- s):     1.8 ms +/- 1.1 ms

Summary: ~tied (1.06x)

4. Long Format - Large Directory

-lah on 7300 files:

Benchmark 1: /sbin/ls -lah --color=always /tmp/lsf-bench/
  Time (mean +/- s):     18.4 ms +/- 3.2 ms

Benchmark 2: ./target/release/lsf -lah --color=always /tmp/lsf-bench/
  Time (mean +/- s):     18.3 ms +/- 3.6 ms

Summary: lsf ran 1.01x faster (effectively tied)

5. Single File

-l Cargo.toml:

Benchmark 1: /sbin/ls -l --color=always Cargo.toml
  Time (mean +/- s):     1.8 ms +/- 1.0 ms

Benchmark 2: ./target/release/lsf -l --color=always Cargo.toml
  Time (mean +/- s):     1.7 ms +/- 1.0 ms

Summary: lsf ran 1.09x faster

6. Recursive Listing

-R /usr/share/doc/:

Benchmark 1: /sbin/ls -R --color=always /usr/share/doc/
  Time (mean +/- s):     17.1 ms +/- 3.1 ms

Benchmark 2: ./target/release/lsf -R --color=always /usr/share/doc/
  Time (mean +/- s):     27.1 ms +/- 2.1 ms

Summary: GNU ls ran 1.59x faster

lsf-Only Features

7. Tree View

--tree --depth 3 on /usr/share/doc/:

Benchmark: ./target/release/lsf --tree --depth 3 --color=always /usr/share/doc/
  Time (mean +/- s):     17.2 ms +/- 3.0 ms

Tree view has no GNU ls equivalent. lsf renders a full tree in ~17ms.

8. Icon Overhead

lsf with icons vs without on 7300 files:

With icons:    13.2 ms +/- 3.2 ms
Without icons: 13.3 ms +/- 3.4 ms

Summary: icon lookup adds ~0% overhead (effectively zero)

The icon lookup system is so fast that enabling/disabling icons makes no measurable difference.

Binary Size

lsf is a single static binary with zero runtime dependencies (no Bash, no Python, no GNU coreutils needed).

How to Reproduce

# Install hyperfine
cargo install hyperfine

# Create test directory (7300 files)
mkdir -p /tmp/lsf-bench
for i in $(seq 1 5000); do touch "/tmp/lsf-bench/file_$i.txt"; done
for i in $(seq 1 500); do mkdir -p "/tmp/lsf-bench/dir_$i"; done
for ext in rs py js ts go c cpp h hpp java rb php css html json yaml toml xml md sh; do
  for i in $(seq 1 100); do touch "/tmp/lsf-bench/sample_${i}.${ext}"; done
done

# Build release binary
cargo build --release

# Run benchmarks
hyperfine --warmup 10 --min-runs 1000 -N \
  '/sbin/ls --color=always src/' \
  './target/release/lsf --color=always src/'

hyperfine --warmup 5 --min-runs 100 -N \
  '/sbin/ls --color=always /tmp/lsf-bench/' \
  './target/release/lsf --color=always /tmp/lsf-bench/'

hyperfine --warmup 10 --min-runs 1000 -N \
  '/sbin/ls -lah --color=always src/' \
  './target/release/lsf -lah --color=always src/'

hyperfine --warmup 5 --min-runs 100 -N \
  '/sbin/ls -lah --color=always /tmp/lsf-bench/' \
  './target/release/lsf -lah --color=always /tmp/lsf-bench/'

hyperfine --warmup 2 --min-runs 10 -N \
  '/sbin/ls -R --color=always /usr/share/doc/' \
  './target/release/lsf -R --color=always /usr/share/doc/'