sharp/docs/performance.md

Performance

Test environment

• AWS EC2 c4.xlarge (4x E5-2666 v3 @ 2.90GHz)
• Ubuntu 16.04.1 LTS (HVM, SSD)
• Node.js v6.9.1

The contenders

• jimp v0.2.27 - Image processing in pure JavaScript. Bilinear interpolation only.
• lwip v0.0.9 - Wrapper around CImg. Compiles outdated, insecure dependencies from source.
• mapnik v3.5.14 - Whilst primarily a map renderer, Mapnik contains bitmap image utilities.
• imagemagick-native v1.9.3 - Wrapper around libmagick++, supports Buffers only.
• imagemagick v0.1.3 - Supports filesystem only and "has been unmaintained for a long time".
• gm v1.23.0 - Fully featured wrapper around GraphicsMagick's gm command line utility.
• sharp v0.17.0 / libvips v8.4.2 - Caching within libvips disabled to ensure a fair comparison.

The task

Decompress a 2725x2225 JPEG image, resize to 720x480 using Lanczos 3 resampling (where available), then compress to JPEG at a "quality" setting of 80.

Results

Module	Input	Output	Ops/sec	Speed-up
jimp (bilinear)	buffer	buffer	1.05	1.0
lwip	buffer	buffer	2.32	2.2
mapnik	buffer	buffer	2.90	2.8
imagemagick-native	buffer	buffer	4.00	3.8
imagemagick	file	file	7.16	6.8
gm	buffer	buffer	7.12	6.8
gm	file	file	7.16	6.8
sharp	stream	stream	27.97	26.6
sharp	file	file	28.69	27.3
sharp	buffer	file	28.81	27.4
sharp	file	buffer	28.99	27.6
sharp	buffer	buffer	29.17	27.8

Greater libvips performance can be expected with caching enabled (default) and using 8+ core machines, especially those with larger L1/L2 CPU caches.

The I/O limits of the relevant (de)compression library will generally determine maximum throughput.

Benchmark test prerequisites

Requires both ImageMagick and GraphicsMagick:

brew install imagemagick
brew install graphicsmagick

sudo apt-get install imagemagick libmagick++-dev graphicsmagick

sudo yum install ImageMagick-devel ImageMagick-c++-devel GraphicsMagick

Running the benchmark test

git clone https://github.com/lovell/sharp.git
cd sharp
npm install
cd test/bench
npm install
npm test