A developer attempted to reduce the size of all npm packages by 5% by replacing all spaces with tabs in package.json files. This seemingly minor change exploited a quirk in how npm calculates package sizes, which only considers the size of tarballs and not the expanded code. The attempt failed because while the tarball size technically decreased, popular registries like npm, pnpm, and yarn unpack packages before installing them. Consequently, the space savings vanished after decompression, making the effort ultimately futile and highlighting the disconnect between reported package size and actual disk space usage. The experiment revealed that reported size improvements don't necessarily translate to real-world benefits and underscored the complexities of dependency management in the JavaScript ecosystem.
This post provides a high-level overview of compression algorithms, categorizing them into lossless and lossy methods. Lossless compression, suitable for text and code, reconstructs the original data perfectly using techniques like Huffman coding and LZ77. Lossy compression, often used for multimedia like images and audio, achieves higher compression ratios by discarding less perceptible data, employing methods such as discrete cosine transform (DCT) and quantization. The post briefly explains the core concepts behind these techniques and illustrates how they reduce data size by exploiting redundancy and irrelevancy. It emphasizes the trade-off between compression ratio and data fidelity, with lossy compression prioritizing smaller file sizes at the expense of some information loss.
Hacker News users discussed various aspects of compression, prompted by a blog post overviewing different algorithms. Several commenters highlighted the importance of understanding data characteristics when choosing a compression method, emphasizing that no single algorithm is universally superior. Some pointed out the trade-offs between compression ratio, speed, and memory usage, with specific examples like LZ77 being fast for decompression but slower for compression. Others discussed more niche compression techniques like ANS and its use in modern codecs, as well as the role of entropy coding. A few users mentioned practical applications and tools, like using zstd for backups and mentioning the utility of brotli. The complexities of lossy compression, particularly for images, were also touched upon.
Summary of Comments ( 47 )
https://news.ycombinator.com/item?id=42840548
HN commenters largely praised the author's effort and ingenuity despite the ultimate failure. Several pointed out the inherent difficulties in achieving universal optimization across the vast and diverse npm ecosystem, citing varying build processes, developer priorities, and the potential for unintended consequences. Some questioned the 5% target as arbitrary and possibly insignificant in practice. Others suggested alternative approaches, like focusing on specific package types or dependencies, improving tree-shaking capabilities, or addressing the underlying issue of JavaScript's verbosity. A few comments also delved into technical details, discussing specific compression algorithms and their limitations. The author's transparency and willingness to share his learnings were widely appreciated.
The Hacker News post "My failed attempt to shrink all NPM packages by 5%" generated a moderate amount of discussion, with several commenters exploring the nuances of the original author's approach and offering alternative perspectives on JavaScript package size optimization.
Several commenters questioned the chosen metric of file size reduction. One commenter argued that focusing solely on file size misses the bigger picture, as smaller file sizes don't always translate to improved performance. They suggested that metrics like parse time, execution time, and memory usage are more relevant, especially in a browser environment where parsing and execution costs often outweigh download times. Another commenter echoed this sentiment, pointing out that gzip compression already significantly reduces the impact of file size during transmission. They suggested that focusing on improving the efficiency of the code itself, rather than simply reducing its character count, would be a more fruitful endeavor.
There was some discussion around the specific techniques the original author employed. One commenter questioned the efficacy of removing comments and whitespace, arguing that these changes offer minimal size reduction while potentially harming readability and maintainability. They pointed out that modern minification tools already handle these tasks efficiently. Another commenter suggested that the author's focus on reducing the size of individual packages might be misguided, as the cumulative size of dependencies often dwarfs the size of the core code. They proposed exploring techniques to deduplicate common dependencies or utilize tree-shaking algorithms to remove unused code.
Some commenters offered alternative approaches to package size reduction. One suggested exploring alternative module bundlers or build processes that might offer better optimization. Another mentioned the potential benefits of using smaller, more focused libraries instead of large, all-encompassing frameworks. The use of WebAssembly was also brought up as a potential avenue for performance optimization, albeit with its own set of trade-offs.
A few commenters touched on the broader implications of package size in the JavaScript ecosystem. One expressed concern over the increasing complexity and size of modern JavaScript projects, suggesting that a greater emphasis on simplicity and minimalism would be beneficial. Another commenter noted the challenges of maintaining backwards compatibility while simultaneously pursuing optimization, highlighting the tension between stability and progress.
Finally, there were a couple of more skeptical comments questioning the overall value of the original author's experiment. One suggested that the effort expended on achieving a 5% reduction in package size might not be justified given the marginal gains. Another simply stated that the whole endeavor seemed like a "weird flex."