Check Gzip Compression

com > Apache & nginx Settings , disable it, or use the following article instead: How to enable gzip compression in nginx on a Plesk server. If it is enabled on the server side, it serves the compressed form of HTML, stylesheets and Javascript files. org Plugin Page Check and Enable GZIP compression. Check GZIP compression allows the server to transfer information more quickly. As devices get newer and more powerful, the software that comes with them gets bigger and more complex. With "Check GZIP compression" testing process is much easier than it sounds!. gzip also refers to the associated compressed data format used by the utility. Let’s check if HTML file named test. How effective is gzip compression?. All scripts are successfully compressed to *. What is gzip compression. Just enter your website URL, and click the submit button. Navigate to ‘/site/wwwroot’, there you will find the ‘web. Before you start, you must know Gzip compression status of your website. Note: The potential savings that Lighthouse lists are the potential savings when the response is encoded with GZIP. Tests were not run in parallel. Previously, by convention, it was used under the applicaion type, as application/x-gzip and when it was released, it was expected to be application/gzipped but present practice is to instead use the MIME encoding field such that the base data type is preserved. Compression Test How much smaller can your site images be? Website image optimization quick test Paste your website/image URL below and see how it performs. HTTP compression uses public domain compression algorithms, like gzip and compress, to compress XHTML, JavaScript, CSS, and other text files at the server. We have already discussed an excellent method for CSS compression , and in this article we share a super-easy technique for compressing all PHP content without editing a single file. You can use the Check GZIP Compression tool to do so. Validate if compression is enable or not: In chrome browser open up developer tools –> go to Network tab and check size of the content: As you see above actual size 9. There’s no reason to not use it these days. The level of compression. If your site is PHP based, there is an alternative (not recommended) method to apply gzip compression. YSlow says it's not, but 5 out of 6 websites that do the test say it is. But the guys at HAProxy Technologies worked hard on it (mainly David Du Colombier and @wlallemand). pigz was written by Mark Adler, and uses the zlib and pthread libraries. I set gzip on in the conf file and now I'm trying to see if it works. The GZIP compression enables the website page to decrease the size of its pages before they go online to the server for a user in browser online. Check GZIP tool helps you to optimize your website online for higher overall performance with the aid of decreasing the loading time of your pages. By default, this value is not enabled. To do this, I will of course need a connection which uses gzip compression. How effective is gzip compression? Compression of your HTML and CSS files with gzip typically saves around fifty to seventy percent of the file size. Other than Google’s tool there are many tools also offer functions to check the GZIP compression of a webpage. Outbound rewriting can be used together with IIS dynamic compression by using the following workaround:. The “ mod_gzip_on ” line enables the module. Summary GZIP compression is process of zipping or compressing files on server before they get delivered or transferred via network to browser. WinZip ® provides several methods for compressing the files that you add to a Zip file. As devices get newer and more powerful, the software that comes with them gets bigger and more complex. How Using GZIP Compression Helps Your Site's SEO Advanced SEO How to Optimize Your Meta-titles, Descriptions and Keywords Beginner SEO The Importance of a Robots. Under Orion, I used to just allow the filter to check the Accept-Encoding header value and then the filter would handle all gzip'ing requirements: a) set content encoding to gzip b) zip the page contents I'd prefer not to have to set content encoding in the MVC controller servlet since it breaks the pluggability of simply adding a to turn compression on. HTTP Compression, also known as Content-Encoding, is a technique in which content on a server is compressed before delivering the content to the browsers. But my nodejs app already has gzip enabled. Thus double check your. best linux gzip command (gzip compression) with examples Introduction In this article we are going to learn the How to use Linux gzip command (gzip compression) to compress files and directories. Debian based users can enable Gzip module (mod_deflate) using the following command. Whenever possible, each file is replaced by one with the extension. By default, gzip compression is enabled (you can see this with the gzip on directive). Demonstrates how to compress a file to create a. Both algorithms use a sliding window for backreferences. Apparently mod_gzip is not setup by default. Software compression methods such as LZ4 or LZS with lower compression ratio, but high bandwidth on CPUs are not an option in that case. Enabling Gzip compression in Joomla will definitely make the website faster. Note: The potential savings that Lighthouse lists are the potential savings when the response is encoded with GZIP. tar test # pure tar only. If you want to check if the GZIP compression has already been enabled on your site, all you have to do is to search the Internet and look for’GZIP compression online check’. When using the first two formats, gunzip checks a 32 bit CRC. Gzip replaces patent-encumbered data compression algorithms. The visitors' web browser then automatically decompresses the pages. Enter the address of a specific page or file to check. Why you need to Enable Gzip Compression on Your WordPress Website. From popular algorithms gzip and Brotli are supported. gzip files are bigger than Brotli files, but faster to build, and natively supported by all browsers over both http and https. To Gzip Compression, we need to include some codes in. Not all servers support Gzip, check whether yours supports it. Defending against the BREACH Attack Posted by Ivan Ristic in SSL Labs on August 7, 2013 4:52 AM When Juliano and Thai disclosed the CRIME attack last year , it was clear that the same attack technique could be applied to any other compressed data, and compressed response bodies (via HTTP compression) in particular. io/xqRL GZIP Compression Is A Quick Way To Improve WordPress Site Speed https://youtu. heatshrink: An Embedded Data Compression Library In embedded systems, space is always tight. We check the web server headers in order to find out if Accept-Encoding: br is present on the request we made. Can be given as 0 for no compression up to 9 for maximum compression. Gzip reduces the size of the named files using Lempel-Ziv coding (LZ77). Htaccess or nginx. Unfortunately, I still don't have compression working. PageSpeed Score with WordPress Gzip Compression = 58/100. After the compression the original files will be replaced by the compressed file which has a ". Here you can see how much it is when it is compressed and how much if it was not compressed and much more. lzop $1 All times are user times, measured by the unix time command. All scripts are successfully compressed to *. For both minute and second data, the compression rate of Bzip2 is the highest, followed by Gzip and GzipIO. In addition to archiving, we’ve also added support for compression using gzip. The visitors’ web browser then automatically unzips the pages. GZIP (Tweets) Taking a rather different view and looking at the ability of Brame and GZIP to compress small text samples - in this case a corpus of 100,000 tweets - let's compare the. Quick benchmark on ARM64. gzip is really good at, like, compressing repetitive text and stuff. In this post I will let you know the process to test, enable and disable Gzip compression in Joomla. But just a "curl" call will not work, since you have to add additional headers to indicate you are capable of handling a gzip'd response -- where curl would, by default, expect a normal plain text response. GNU gzip home page, where you can find the latest gzip source code, documentation, and development information. Check Site for gzip Compression. GZIP is based on the DEFLATE algorithm and, while people usually just refer to it as a single compression tool, there are actually different "levels" of GZIP compression. Until now, HAProxy did not include such feature. IIS gZip Compression Not Working after Setting Everything Hi All, I deployed a simple html page with ajax (loading a json file) in my iis 8. 6) Click the button ‘Yes’ near to the option ‘Gzip page compression’. Additional Resources. PageSpeed Score with WordPress Gzip Compression = 58/100. This tool checks your server to see if you have Gzip compression enabled. It helps users to reach them faster. 11 Simple Gzip Examples Posted by Jarrod on July 29, 2015 Leave a comment (2) Go to comments Gzip is used to compress a file in order to reduce disk space, it is quite popular in Linux and UNIX operating systems for this reason. Gzip attempts to truncate only the parts of the file name longer than 3 characters. Note: This implementation of GZip doesn't include CRC32 (Cyclic Redundancy Check) logic, due to this while using standard gzip decoder with "-d" option results in crc related warning and decompression fails. To check if gzip is enabled on your server, you must send a HTTP request containing the Accept-Encoding: gzip header. tar test # pure tar only. If you want to test from WordPress dashboard to test Gzip compression status, you can install “Check and Enable GZIP compression” plugin. 0 20 40 60 80 100 120 140 200 400 600 800 1,000 1,200 1,400 1,600 1,800 2,000 compressed size, bytes Requests delta http1 http1_gzip spdy3 0 20 40 60 80 100 120 140 100 200 300 400 500 600 700 compressed size, bytes Responses delta http1 http1_gzip spdy3. In this tutorial, We provide the basic GZip Command syntax, GZip options & Gzip Command Examples. (The demo project was updated. 015% for large files. GZIP compression reduces the size of pages (HTML/CSS/JS) in the web server before they are sent to the site visitor’s browser. Example: $ gzip -v -t file. If Brotli is used, even more savings are possible. Applications 23 - Compression with gzip With many systems, drive space as well as upload and download times can be important. Introduction. Gzip compression can help to improve your page speeds even further, however, so it’s worth implementing. ` Here we have a string. Compression is always performed, even if the compressed file is slightly larger than the original. If you want to log the compression ratio to a file, here’s the directives to add to enable the mod_deflate GZIP compression ratio logging. How to enable Gzip compression on your website??!!For most people reading this, compression is enabled by adding some code to a file called. But just a "curl" call will not work, since you have to add additional headers to indicate you are capable of handling a gzip'd response -- where curl would, by default, expect a normal plain text response. NET Core we have three options for compression: ASP. In making a choice of compression methods, there are several things to consider, including the type of data you are compressing, your plans for later unzipping the data, and the amount of time you are willing to wait while your data is being compressed. INI file setting. Just input your URL and wait for them to run a GZIP compression check on your website. It compresses the contents delivered to the client. NET GzipStream is known to generate a space-inefficient compression dictionary, AND it includes the Gzip wrapper; for small sets of data this is an unacceptable overhead, but for a 34MB file there is no noticeable impact. Gzip is the most popular and effective compression method currently available and generally reduces the response size by about 70%. What if files on the host are not compressed and are using a lot of bandwidth? You must check them out with the aid of our Check GZIP Compression program. Clients needed to trust that sites will stack, and if a customer were viewing a video, the disturbing buffering message would continue springing up. Check GZIP Compression. 0 Before you upload your code to Panaya's Code Box, you will need to compress the XML file into Zip archive using a standard archiving software like Gzip. With gzip, the only allowed method of compression and decompression is "one-shot", where all the data must be processed at once. " It's also (conveniently) a format understood by all modern browsers, capable of being generated by all modern servers, and it works particularly well on text content. Bzip2, Gzip and GzipIO compression algorithms are used to test minute and second data of an instrument in January 2009 outputted by an instrument. Here an example output, comparing the UNIX gzip / gunzip with the ABAP-GZIP. This program tests web pages for gzip or deflate compression. In order for gzip compression to work it needs two components: 1. LoadModule deflate_module modules/mod_deflate. The advantage for Brotli over gzip is that it uses a dictionary and thus it only needs to send keys. In particular, it will ignore symbolic links. Hope this helps. Apparently mod_gzip is not setup by default. Before you actually go and do any changes, you probably want to check whether your site’s gzipping files is already enabled for your WordPress site. ZIP and GZIP compression library for. As devices get newer and more powerful, the software that comes with them gets bigger and more complex. The statement is true. Summary GZIP compression is process of zipping or compressing files on server before they get delivered or transferred via network to browser. With "Check GZIP compression" testing process is much easier than it sounds!. The gzip compression can be enabled by directly changing httpd conf file. LATEST BLOGS. It sure felt like the copy was taking longer the more compression going on which makes sense actually when you think about it. gz Read the Content of a gzip-compressed File. Online tool to test if Gzip compression is working on your webpages and report file size savings. com or Varvy's gzip compression test. GZip Compression Test allows you to evaluate the compression results of your website in seconds hence providing your better insights for increasing the performance. If the input data is not in a format recognized by gzip , and if the option --stdout is also given, copy the input data without change to the standard ouput: let zcat. -> You can compress Linux files with the open-source “compression tool Gzip or with Zip”, which is recognized by most operating systems. Unfortunately, I still don't have compression working. By using our great tool Check GZIP Compression of website Gzip Checker Compression Test. gz eg ; gzip filename. htaccess file. I recently needed to setup Gzip on my somewhat new Windows 8 VM and had to lookup how to do that. The detection of the input format is automatic. Two compression algorithms are commonly used - deflate and gzip. Hi, thanks,. This saves bandwidth and causes pages to load and be displayed significantly faster. Fiddler is a Web Debugging Proxy which logs all HTTP(S) traffic between your computer and the Internet. Lighthouse lists each response that was sent without text compression. (* The purpose of test is to show that Indy library can not GZIP compress some string String is saved in file uncompresable. We analyzed Gziptest. Check GZIP Compression. Establish some performance baseline before enabling and see how the baseline will be changed after enabling gzip. GZip comes default in every Linux Distros. Hence, enabling text compression on a website helps improve pagespeed. I already mentioned this briefly earlier in this article, and it's actually the easiest step in the process. GZIP compression reduces the size of pages on a web server before they are sent to the visitor's browser. gz; then echo 'file is ok' else echo 'file is corrupt' fi Adding -v will make it actually report the result with a message. Enabling gzip compression on your script / webserver will not only help you achieving a greater score on Google PageSpeed "Enable compression" [1] test, but also allow a faster rendering time on your visitors browser. It is easy to think that if files are smaller, they take up less drive space. A quick benchmark on ARM64 (odroid, Cortex A53), on kernel Image (12MB), use default compression level (-6) because no way to configure the compression level of btrfs. How can I verify that gzip compression is working? Run a test with GTmetrix. Since SSL doesn’t know what data it is transporting, and it could be transporting data which is already compressed, such as a JPG file, or GZIP content from your web site. Gzip should already be enabled on Nginx by default. I already mentioned this briefly earlier in this article, and it’s actually the easiest step in the process. Here, applying GZIP compression would definitely improve the efficiency of transaction. Gzip reduces the size of the named files using Lempel-Ziv coding (LZ77). Sharing your test result so others can see as well: Compression/gzip. I am using xmlrpc-3. -c – to create archive, -v – verbose, -f for archiving file, -z to compress files in gzip format. We developed this program as a replacement for compress because of the Unisys and IBM patents covering the LZW algorithm used by compress. Gzip is short for GNU zip; as the program was created as a free software replacement for the compression program used in early Unix systems. We check the web server headers in order to find out if Accept-Encoding: br is present on the request we made. Jean-loup is also the primary author of gzip(1), the author of the comp. NET Core supports response compression. However, you can get better compression by compressing all members at once: cat file1 file2 | gzip > foo. Defending against the BREACH Attack Posted by Ivan Ristic in SSL Labs on August 7, 2013 4:52 AM When Juliano and Thai disclosed the CRIME attack last year , it was clear that the same attack technique could be applied to any other compressed data, and compressed response bodies (via HTTP compression) in particular. The GZIP compression enables the website page to decrease the size of its pages before they go online to the server for a user in browser online. GZIP compression is bundling (zipping) pages on a web server before the page is sent to the visitor. Check the Gzip compression information. How to enable or disable static and dynamic compression for a server. You don't want to gzip them, it will only make them bigger. gz If a compressed file consists of several members, the uncompressed size and. Use the z flag for gzip compression or the j flag for bzip compression. While compression re-ducesnetworktraffic,ifnotproperlyimplementeditmay make an application vulnerable to DoS attacks. This generally means that the standard uncompress does not check its input, and happily generates garbage output. Text Compression Methods. Therefore, it’s a standard practice to enable gzip compression in web servers. Gzip is a method of compressing files (reducing file size) so that data transfer over the network is faster and loads your site in just a few seconds. Both algorithms use a sliding window for backreferences. Create a file, phpinfo. IIS Compression is a collection of compression scheme providers that add support for Brotli compression and provide a better implementation of Gzip and Deflate compression than those that ship with IIS. Tar BZ2 archives can also be extracted from the command line. htaccess Compressing your website files, especially the text files, with mod_gzip or mod_deflate on Apache not only save heaps of network bandwidth, but also speed up downloading your website up to 70%. There is a nice free tool for Internet Explorer which can be used to see if your server's http responses are compressed: Fiddler. Check Compression with Our Free SEO Tool. A simple Gzip checker allows you to quickly test if Gzip is enabled on your website, verify that your site has Gzip\deflate compression enabled. Most of my traffic comes from modern browsers, and quite frankly, most. Putting in a request header of ‘Accept-Encoding: compress, gzip’ will prompt the server to respond with compression. com will confirm that web sites run with node. @Lenor If you mean how enabling gzip compression affect server performance - the only way is to monitor the server performance. Under Orion, I used to just allow the filter to check the Accept-Encoding header value and then the filter would handle all gzip'ing requirements: a) set content encoding to gzip b) zip the page contents I'd prefer not to have to set content encoding in the MVC controller servlet since it breaks the pluggability of simply adding a to turn compression on. CL_ABAP_GZIP is a standard SAP object class available within R/3 SAP systems depending on your version and release level. If this happens to you then don’t panic. It was developed by Jean-Loup Gaily and Mark Alder, and released on October 31, 1992. If it is missing, assume GZIP. After the compression the original files will be replaced by the compressed file which has a “. Enabling gzip compression on your site will dramatically reduce the amount of data sent from your server to the visitors browsers, thus increasing the page-load speed. 0 and later has native support for Brotli compression in its zlib module. Gzip should already be enabled on Nginx by default. If your site is PHP based, there is an alternative (not recommended) method to apply gzip compression. I am using xmlrpc-3. In the client I run the following:. The time is the real entry from the time command. Yes, the gzip file header starts with bytes "1F 8B 08"although the last byte (08 - the compression method) may have other values in the future. Enable and test gzip compression support on your web server. $ tar cvf test. 6) Click the button ‘Yes’ near to the option ‘Gzip page compression’. 49% savings when gzipping the uncompressed. Data Compression (gzip)¶ BidSwitch supports JSON and Compressed JSON (gzip) as data formats for bid requests and bid responses. Enabling GZIP compression from the server is one standard practice. com - it should identify whether or not gzip compression is happening. gzip_comp_level 1. Compression Benchmarks 07 Jun 2017. Dynamic Content. js, apache, nginx and other servers are properly delivering compressed results in response to requests. Following a few performance related blogs recently this one is following a similar trend and is going to look at Brotli compression. File Compression and Archiving with Gzip, Zip, and Tar. The gzip utility reduces the size of the named files using adaptive Lempel-Ziv coding, in deflate mode. But it seams that there is a kind of trailer in an authentic gzip file which is missing in the output of CL_ABAP_GZIP. 86 bpc on alice and 1. For both minute and second data, the compression rate of Bzip2 is the highest, followed by Gzip and GzipIO. GZIP Compression Enabled: enable or disable GZIP compression for all Web applications. NET Core does compression. and check if GZIP compression is working for your site. Processing compressed content works if the browser has requested compressed content; otherwise it ignores the HTTP header Content-Encoding: gzip although it would be able to decompress the content. GZIP is based on the DEFLATE algorithm and, while people usually just refer to it as a single compression tool, there are actually different "levels" of GZIP compression. The core receives uncompressed input files and produces compressed files. This allows your server to deliver these (smaller) files to a site visitor much more quickly. The ideal way to enable compression in Litespeed is to do it through the configuration under “tuning”. Under “Add Reference”click the “Browse” tab. Grab Your Free 17-Point WordPress Pre-Launch PDF Checklist: http://vid. On average - 41. Enable text compression on the server(s) that served these responses in order to pass this audit. Level 0 = no compression, then level 1-4 are roughly the fastest to compress with reasonable quality. tar in AIX by default does not support compression. There are two caveats to this, however: some compression formats cannot be split for parallel processing, and others are slow enough at decompression that jobs become CPU-bound, eliminating your gains on IO. The tool doesn't create compressed files, so generally the size of the EOT is about the size of the input TTF. After the compression the original files will be replaced by the compressed file which has a “. Title: Check GZIP compression Description: Check if GZIP compression on your web server is enabled and save at least 50% of your bandwidth usage. This for sure is one of the easiest ways to check if the GZIP is enabled on your server. Gzip Compression test GZip is a form of data compression of web page and makes it smaller before sending them over to the browser. com - it should identify whether or not gzip compression is happening. The Knowledgebase article is one of the ones that I referenced. 67GHz, 8GB DDR3 RAM, tmpfs as ram disk) Key Results:. IPS will drop HTTP traffic with multiple encoding schemes, only if Gzip enforcement is enabled and the "drop compressed traffic if inspection is stopped" was checked. It's worth noting that for IIS 7 - 9 compression settings aren't site scoped, they are at the server level, but in IIS 10 you can now configure this per site. Enabling gzip compression on your site will dramatically reduce the amount of data sent from your server to the visitors browsers, thus increasing the page-load speed. Quick benchmark on ARM64. Check GZIP compression allows the server to transfer information more quickly. GZIP is a generic compression method that can be applied to any stream of bits. Some of the commonly used commands are: – The compress command – The gzip command – The zip command. Try compression checker to verify whether GZIP is enabled on a specific web page. You can go back to compression for your site and ensure Dynamic Compression is checked. Brotli is a new standard that provides better compression than gzip - it's now supported in all 4 major browsers. Every VU (virtual user) runs the same test case, with a 1-second delay in between. GZIP content-encoding HTTP Response Header. Thanks, I will take a look at that with the host. Login to your web host server. 12 - 24/02/11: * Fixed an inconsistency with the Tag element. By default, this value is not enabled. To view these settings open up IIS Manager. In the Compression pane, check the boxes to enable static or dynamic compression, or remove the check marks to disable static or dynamic compression. net and there are people in this newsgroup who have the solution. Gzip compression is one of the tools to make your website load faster. NET with the same input file. When using the gzip utility, the -1 option is also known as best compression and results in a higher compression ratio. Compression is a simple, effective way to save bandwidth and speed up your site. Check GZIP compression. HTTP compression is a capability that can be built into web servers and web clients to improve transfer speed and bandwidth utilization. What is Brotli compression? Google’s Brotli is the new replacement for the old gzip and deflate compression. How to Check Gzip Compression. Essentially what this does is, is asks the server compress all the files before sending them to the user. Htaccess or nginx. If you sometimes check if GZIP compression is enabled or not on some other sites. sudo a2enmod deflate Step 2 - Configure Gzip Compression. bits and the dynamic length would be 433 bits. com - it should identify whether or not gzip compression is happening. As devices get newer and more powerful, the software that comes with them gets bigger and more complex. Tests were on Fedora 17 x86_64 with a Intel Core i5-3360M processor and a Intel SSDSC2BW180A3 drive. -c – to create archive, -v – verbose, -f for archiving file, -z to compress files in gzip format. I am using xmlrpc-3. In addition, you must include the expired parameter to check the value of the Expires header field. All you have to do is provide the URL to your website, then run the search. Each file is renamed to the same name plus the extension “. Better compressors “learn”, using prior input to improve compression on subsequent input. This will add the compression module to the test ASP. The SCO compress -H format (lzh compression method) does not include a CRC but also allows some consistency checks. Htaccess or nginx. htaccess file gives a 500 error, and having asked the host again they have now told me that gzip compression is not available on their shared hosting server. Gzip will only attempt to compress regular files. FOLLOW US. Sur Check GZIP compression. This saves a lot of traffic and makes pages load and display much faster. Establish some performance baseline before enabling and see how the baseline will be changed after enabling gzip. GZIP Compression Best Practices for Apache. We looked into this in the past, and for engineering reasons decided not to enable it at that time. But the guys at HAProxy Technologies worked hard on it (mainly David Du Colombier and @wlallemand). I tried compressing one of the archive log files. Jan 18, 2019 #2. org/http-compression. Compression is an easy way to reduce the size of packages and in the same time increase the speed of communication between client and server. In order to check if the GZIP compression is already enabled on your site, you have to search the Internet and check for ‘GZIP compression online check’. No, the image compression check (particularly for jpegs) is re-compressing the images at a standard quality level (and stripping out the meta data). htaccess file. Prior to Domino 8. I set gzip on in the conf file and now I'm trying to see if it works. com - it should identify whether or not gzip compression is happening. htaccess Gzip Compression. GZIP compression is used to reduce the traffic between the web servers and the browser. htaccess file and website have to be crafted in such a way to enable GZIP compression. GZIP is a generic compression method that can be applied to any stream of bits. Official documentation; Popular search terms: nginx gzip. To check the Brotli compression on the test server you can use the nightly build of the Firefox browser, which also supports this format. Gzip compression using PHP. gzip 7,8,9 use an inordinate amount of resources for a minimal improvement in results. config’ file. If you sometimes check if GZIP compression is enabled or not on some other sites. duplichecker. Let me make something clear. See the mtime attribute for more details. Newer versions of HBase have the ability cache block in compressed form, but I did not test this here. Considering the benefits of GZIP compression, it's important to check whether your site has enabled it or not. It is sending the header Accept-Encoding: gzip, deflate - but only if using HTTP/1. For me personally it is a mandatory step in either the website construction or the Search Engine Optimisation process. ZipAccel-C is a custom hardware implementation of a lossless data compression engine that complies with the Deflate, GZIP, and ZLIB compression standards. pigz, which stands for parallel implementation of gzip, is a fully functional replacement for gzip that exploits multiple processors and multiple cores to the hilt when compressing data. Force compression or decompression even if the file has multiple links or the corresponding file already exists.