Viewed 22k times. Improve this question. David David 5, 15 15 gold badges 51 51 silver badges 89 89 bronze badges. Add a comment. Active Oldest Votes. Improve this answer. LearningFast LearningFast 1, 12 12 silver badges 12 12 bronze badges. Mark Adler Mark Adler Thanks for the response and for the link to the benchmarks.
My main concern was whether doing so would put any extra burden on the client having to decompress content. Based on those results it would seem not - in fact it could be even faster.
But for all practical purposes, this shouldn't be measurably worse for clients unless you try to port chrome to a calculator. The reason decompression is faster at a higher compression level on the same input data is very simply due to the fact that the decompressor has less input data that it has to process. MarkAdler uff I just realized that you're that Adler. I'm humbled by the fact that you read my answer on compression! RonJohn thanks for the heads up! Replaced it with an archive. Sign up or log in Sign up using Google.
Sign up using Facebook. Update As mentioned in the comments, I have been unable to reproduce the original result with gzip.
Working on the assumption that I accidentally used a different compression format in that original quick test I've repeated with gzip and updated the figures below accordingly. It very much depends on the data being compressed.
If the data has low redundancy to start with, for instance, the archive contains images files in a format that is compressed natively gif, jpg, png, For binary files like program executables you might see up to compression, for plain text, HTML or other markups or or more is not unlikely. You can check how much data would result from unpacking a gzip file, without actually writing its uncompressed content to disk, with gunzip -c file.
If compressed content is a tar file containing many many small files you might find that noticeably more disk space is required to unpack the full archive, but in most circumstances, the count returned from piping gunzip output through wc is going to be as accurate as you need. Look for The maximum compression ratio of the deflate format is This is because the longest run that can be encoded is bytes. You can get more compression by gzipping the result of gzip.
Normally that doesn't improve compression, but for very long runs it can. By the way, the LZ77 approach used by deflate is more general than run-length encoding. This allows copying a string from some distance back, or replicating a byte as in run-length for a distance of one, or replicating triples of bytes with a distance of three, etc.
The compression ratio of any compression algorithm will be a function of the data being compressed besides the length of that data. Here is an analysis at MaximumCompression , Look at one of the samples like,. Summary of the multiple file compression benchmark tests. So maximal ratio looks to be around x.
Know how your site or web app is performing with real user insights. Pinpoint the root cause down to a poor-performing line of code. Integrated, cost-effective, hosted, and scalable full-stack, multi-source log management. Quickly jump into the relevant logs to accelerate troubleshooting. The size of the web is growing exponentially. From to , the average size of a website increased from 2. Considering 1. The question is, how do we keep websites fast even as they get bigger and bigger?
One answer is in data compression using gzip. Gzip is a data compression algorithm capable of compressing and decompressing files quickly. The name also refers to two other technologies: the software used to compress and decompress files, and the format those files are stored in. Gzip can compress almost any file type, from plain text to images, and is fast enough to compress and decompress data on-the-fly. Web servers use gzip to reduce the total amount of data transferred to clients.
When the web server receives the request, it generates the response as normal, then checks the Accept-Encoding header to determine how to encode the response.
If the server supports gzip, it uses gzip to compress each resource. It then delivers the compressed copies of each resource with an added Content-Encoding header , specifying that the resource is encoded using gzip. The browser then decompresses the content into its original uncompressed version before rendering it to the user. However, this comes at a cost. Article's content. Latest Blogs. Application Security Application Delivery.
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