On Ubuntu (18.04 and 20.04), installing zlib reported unable to locate package zlib: $ sudo apt install zlib Reading package lists… Done Building dependency tree Reading state information… Done E: Unable to locate package zlib How to install zlib in Ubuntu? Install zlib in Ubuntu from Ubuntu package repo In Ubuntu, the zlib package is
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Tag: gzip
How to split a gzip file to several small ones on Linux?
Posted onI have a very large (e.g. 100GB) .gz file and would like to split it into smaller files like 8GB/each for storage/copying. How to split a gzip file to several small ones on Linux? You may use the tool split to split a file by sizes. An example to split a large.tgz to at most
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SEEK_HOLE and SEEK_DATA: efficiently archive/copy large sparse files
Posted onHow to efficiently archive a very large sparse file, say 1TB? The sparse file may contains a small amount of data, say 32MB. SEEK_HOLE and SEEK_DATA The SEEK_HOLE/SEEK_DATA functionalities play the trick and makes `tar` and `cp` handle the large sparse file very efficiently. `lseek` with `SEEK_HOLE` returns the offset of the start of the
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Which Checksum Tool on Linux is Faster?
Posted onIt is common practice to calculate the checksums for files to check its integrity. For large files, the checksum computation is slow. Now I am wondering why it is so slow and whether choosing another tool will be better. In this post, I try three common tools md5sum, sha1sum and crc32 to compute checksums on
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Speeding Up the Site With Apache GZIP Compression
Posted onWe can speed up the site with compression while save bandwidth at the same time. As most of the modern browsers support gzip encoding, we can set it up to let the users enjoy faster speed. The Apache mod_deflate is easy to set up and standard. It compress the content on the fly. We can
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Speeding Up the Site by Using PHP GZIP Compression
Posted onCompression is a simple way to speed up the site. PHP’s gzip compression is excellent. And using it is very convenient: Simply put these codes before any HTML content at the beginning of the PHP script: <?php if (substr_count($_SERVER[‘HTTP_ACCEPT_ENCODING’], ‘gzip’)) ob_start(“ob_gzhandler”); else ob_start(); ?> In WordPress, the suitable position for these codes is the beginning
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How to Set Up Socks Proxy Using SSH Tunnel
Posted onWe can set up a socks proxy on top of a SSH tunnel. Besides the common proxy functions, such as web browsing, the proxy on top of SSH tunnel also ensures the security between the browser and the proxy server (the SSH server). In this post, we introduce and explain how to set up a
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How to Compress/Uncompress Files in Linux Using gzip, bzip2, 7z, rar and zip
Posted onCompress/uncompress files are frequent operations. The normal tools for compressing/uncompressing in Linux is gzip, bzip2, 7z, rar and zip. This post introduces how to compress and uncompress file in Linux using these tools. We use best compressing rate with all these tools and mark the options for “best rate” in bold fonts. We can delete
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