How to Use the Command 'pigz' (with Examples)

Pigz, short for “Parallel Implementation of GZip,” is a powerful, multithreaded zlib compression utility. Unlike gzip, which compresses files using a single processor, pigz can utilize multiple processors and cores, resulting in significantly faster compression times. This utility is particularly beneficial for compressing large files or directories when time efficiency is of the essence. Pigz can seamlessly handle both compression and decompression tasks, making it a versatile tool for various file management scenarios.

Compress a file with default options

Code:

pigz path/to/file

Motivation:

Using the default options of pigz is suitable when you want a quick and effective compression without delving into specific settings. It permits the automatic balancing of speed and compression ratio. This is particularly useful in situations where the computational resources are limited, and you just need a decent compression to conserve space.

Explanation:

• pigz: Calls the pigz utility to perform compression.
• path/to/file: Specifies the file you intend to compress.

Example Output:

After execution, the original file will be replaced by a new file with the same name, appended with a .gz extension (e.g., file.gz).

Compress a file using the best compression method

Code:

pigz -9 path/to/file

Motivation:

When maximum compression is desired to save as much space as possible, even at the cost of additional time spent on the compression process, the -9 option is ideal. This is particularly important when dealing with storage limitations or when sharing data over a network with bandwidth constraints.

Explanation:

• pigz: Initiates the pigz utility.
• -9: Instructs pigz to apply the highest level of compression, resulting in a smaller file size.
• path/to/file: Specifies the path to the file that will be compressed.

Example Output:

The output is a highly compressed file with a .gz extension. Although it takes longer to compress, the file size is minimized as much as the zlib compression algorithm can allow.

Compress a file using no compression and 4 processors

Code:

pigz -0 -p4 path/to/file

Motivation:

There are instances where the primary goal is not to compress the contents, but to take advantage of pigz’s parallelism for faster file packaging. Using no compression ensures the process is swift, which is useful when the button is focused on wrapping files for transfer rather than reducing file size.

Explanation:

• pigz: Calls the pigz utility.
• -0: Designates no compression; the data is simply stored.
• -p4: Utilizes 4 processors to manage the task concurrently for faster execution.
• path/to/file: The file you wish to encase in a gzip wrapper.

Example Output:

The resulting output file is a wrapped file a .gz extension, processed quickly due to multiple processors being employed, although not compressed in size.

Compress a directory using tar

Code:

tar cf - path/to/directory | pigz > path/to/file.tar.gz

Motivation:

To compress entire directories, capturing their structure within a single compressed archive, the combination of tar and pigz is an efficient solution. This method is vital when you need to backup, transfer or store nested files while maintaining their hierarchy.

Explanation:

• tar cf -: Creates an uncompressed tarball of the specified directory.
• path/to/directory: The directory being targeted for backup.
• |: A pipe that takes the output from tar and uses it as input to pigz.
• pigz: Compresses the tarball created by tar.
• >: Redirects the compressed output to a specified file.
• path/to/file.tar.gz: Designates the output file for the compressed directory archive.

Example Output:

The output is a .tar.gz file which encapsulates the original directory structure in its entirety while being compressed for efficient storage.

Decompress a file

Code:

pigz -d archive.gz

Motivation:

Sometimes, the necessity arises to access the original contents of a compressed file. Decompression is essential for retrieving these files in their usable form. It’s particularly useful for extracting compressed backups or archives for further processing or modification.

Explanation:

• pigz: Executes the pigz utility.
• -d: Directs pigz to decompress the specified file, essentially reversing the compression.
• archive.gz: The compressed file that needs decompression.

Example Output:

Once executed, the decompressed file will replace the original .gz file, restoring it to its pre-compression state.

List the contents of an archive

Code:

pigz -l archive.tar.gz

Motivation:

Before decompressing a large archive, it’s often helpful to verify its contents to ensure that it contains the required files or to attain an understanding of its internal structure. Listing the files without extraction can save time and computational resources, particularly when dealing with extensive archives.

Explanation:

• pigz: Executes the pigz utility.
• -l: Allows listing of the contents without full decompression.
• archive.tar.gz: Indicates the archive whose contents you wish to list.

Example Output:

You will receive a list of the files contained within archive.tar.gz, displayed directly in the terminal.

Conclusion:

Pigz provides a versatile and efficient solution for handling file compression and decompression with added benefits of speed through its multithreading capabilities. Whether maximizing storage efficiency with highest compression settings or aiming for rapid processing with multiple processors, pigz caters to a wide variety of use cases that suit different project requirements.