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Questions tagged [gzip]

Gzip is any of several software applications used for file compression and decompression. The term usually refers to the GNU Project's implementation, "gzip" standing for GNU zip. It is based on the DEFLATE algorithm, which is a combination of Lempel-Ziv (LZ77) and Huffman coding.

Gzip is any of several software applications used for file compression and decompression. The term usually refers to the GNU Project's implementation, "gzip" standing for GNU zip. It is based on the DEFLATE algorithm, which is a combination of Lempel-Ziv (LZ77) and Huffman coding.

Gzip is based on the DEFLATE algorithm, which is a combination of LZ77 and Huffman coding. DEFLATE was intended as a replacement for LZW and other patent-encumbered data compression algorithms, which, at the time, limited the usability of compress and other popular archivers.

"Gzip" is often also used to refer to the gzip file format, which is:

  • a 10-byte header, containing a magic number, a version number and a time stamp
  • optional extra headers, such as the original file name
  • a body, containing a DEFLATE-compressed payload
  • an 8-byte footer, containing a CRC-32 checksum and the length of the original uncompressed data

source: wikipedia

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how to enable iis 7 dynamic content compression?

I've turned on dynamic content compression in IIS 7, but Fiddler is showing that my dynamic pages are still being served without content-encoding: gzip. Static content compression is working fine on the same servers. Not sure if it matters but most…
davidcl
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Problems with Gzip compression on Amazon CloudFront

I had a CloudFront distribution configured with S3 as an origin. I have enabled "Compress Objects Automatically" as per Amazon guide. Waited for the distribution status to display "online" then invalidated all files. My Response headers…
Lukigi
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gzip on httpd or on Tomcat?

In a Java web application running in an Apache Tomcat servlet container with an Apache httpd in front of it: is it better to use enable GZIP compression on Tomcat or on httpd level? is it better to have SSL enabled in Tomcat or on…
mhaller
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gzip_ratio not printing in nginx logs

I'm configuring the nginx access_log to output in JSON format to use with other tools. The data I want includes info about the compression. I have gzip on, but the only thing I'm getting for the gzip_ratio is -. To confirm, the embedded var is…
gotmikhail
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dd command piped over gzip and ssh faster and faster as dd progresses

I am running the following command to copy a LVM from one host to another: dd if=/dev/vg_1/lv1 conv=noerror,sync bs=4M | gzip | ssh user@ip 'gzip -d | dd of=/dev/vg_2/lv1 bs=4M' To begin with I was getting a speed of about 11 MB/s about an hour…
user2284355
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IIS 7.5 inconsistently Gzips files (with PHP & ASP.NET)

I made some changes to the web.config of a server running IIS 7.5 improve the performance (mostly front-end). A 3rd party testing tool says the site is running "PHP/5.3.10, ASP.NET" and if memory serves, it is ASP.NET 4.5 I think it's due to the odd…
adam-asdf
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Why is gzip compression varying in efficiency in IIS?

While running Fiddler, I noticed something odd in a request for a static ~5MB XML file to my server: Despite sending byte-for-byte identical headers (Edit: Including the headers), the responses were different: Response A: 1. 700KB of gzip…
Brian
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Turn off gzip for a location in Nginx

How can gzip be turned off for a particular location and all its sub-directories? My main site is at http://mydomain.com and I want to turn gzip off for both http://mydomain.com/foo and http://mydomain.com/foo/bar. gzip is turned on in nginx.conf. I…
Nyxynyx
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How to disable gzip compression for particular virtual host apache

Im using Apache and I have enabled zip compression to all my virtual host domain. However, I want to disable the gzip compression on one particular virtual host only. I try this method. All separated virtual host file i.e. domain.com.conf has this…
James W.
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Enable gzip on Nginx

Yes, I know that there are a lot of other questions that seem exactly like this out there. I think I must've looked all of them. Twice. In desparation, I'm adding another in case my specific configuration is the issue. Bear with me. First, the…
Rob Wilkerson
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Apache mod_deflate not compressing javascript and css files?

"GET /Symfony/web/app.php/app/dashboard HTTP/1.1" 4513/37979 (11%) "GET /Symfony/web/css/application.css HTTP/1.1" -/- (-%) "GET /Symfony/web/js/application.js HTTP/1.1" -/- (-%) "GET /Symfony/web/js/highcharts.js HTTP/1.1" -/- (-%) "GET…
gremo
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tar gzip slowing down server

I have a backup script that: compress some files generate md5 copy the compressed file to another server. the other server finishes comparing MD5 (to find copy errors). Here it's the core script: nice -n 15 tar -czvf $BKP $PATH_BKP/*.* \ | xargs…
Josir
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Combine two or more compressed files

I have 2 gz files those I need to merge into one -- that is to say I want to combine two .gz files into one such that when I extract the combined file I get a single file containing the concatenation of the original input files. time join <(zcat…
shantanuo
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Enabling HTTP Compression in WebSphere Application Server 7

I know the correct way of enabling gzip HTTP Compression for a WebSphere Application Server is to activate and configure the mod_gzip module in the IBM HTTP Server connected/installed in this environment. However, our WAS 7 environments don't have…
Filipe Fedalto
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Should I serve compressed PDFs?

I'd like to know if there's a general rule of thumb wheter to enable gzipping for PDF files or not. I use NGINX but I think this would be helpful for Apache users as well. Thanks.
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