📢 Git 2.41: New Features and Improvements Enhance Git's Performance

What's new and improved in Git 2.41?

One of the notable improvements in Git 2.41 is the enhanced handling of unreachable objects within a repository. Git repositories consist of various objects, including blobs, trees, and commits, which serve as the foundation of the repository's structure and history.

Unreachable objects are those that cannot be reached from any branch or tag in the repository's history. In previous versions of Git, these objects were stored as loose copies until they aged out, leading to potential repository size bloat and inode exhaustion.

To address this issue, Git 2.37 introduced "cruft packs", which store unreachable objects together in a packfile and use an auxiliary *.mtimes file to track object ages. In Git 2.41, cruft pack generation is enabled by default, optimizing repository size and performance.

Another significant improvement in Git 2.41 is the introduction of on-disk reverse indexes as a default feature. These reverse indexes store information similar to packfile indexes but are pre-computed and stored alongside the corresponding packfile as *.rev files.

This enhancement significantly speeds up operations in large repositories, particularly for tasks such as pushing changes or determining the on-disk size of an object. With the on-disk reverse indexes enabled by default, Git users can expect improved performance when running git gc after upgrading.

Test results have shown a 1.49x speed-up for CPU-intensive git push operations and an impressive 77x speed-up for computing the size of a single object using git cat-file --batch='%(objectsize:disk)'.

Git 2.41 also extends the credential helper protocol to support passing WWW-Authenticate headers between credential helpers and the services they authenticate with. This enhancement enables finer-grained access control to Git repositories by allowing users to scope their requests.

Additionally, the new for-each-ref formatting atom, %(ahead-behind:<base>), allows users to directly request information about the number of commits ahead or behind a specific base. This feature improves efficiency by performing the calculation in a single walk, making it more effective than previous methods.

In terms of usability and scripting capabilities, Git 2.41 introduces several improvements. The git fetch command now supports the --porcelain option, which provides a scripted-friendly output format. This option simplifies the process of programmatically processing fetch results.

Moreover, the fetch.hideRefs option allows users to exclude parts of the references in their local repository from the connectivity check performed during a fetch operation. This feature is particularly beneficial for users with numerous remotes or resource-constrained systems, as it significantly reduces the time required for the connectivity check.

Lastly, Git 2.41 enhances the git fsck command to check for corruption in reachability bitmaps and on-disk reverse indexes. These checks ensure data integrity by verifying the correctness of trailing checksums and the values stored in the *.rev file associated with on-disk reverse indexes. By incorporating these checks, Git provides an added layer of protection against potential data corruption.

Git 2.41 represents another significant milestone in the development of this popular distributed version control system. With improved handling of unreachable objects, on-disk reverse indexes, extended credential helper protocol, and enhanced scripting options, Git users can expect a more efficient and reliable experience. By embracing community contributions, Git continues to evolve and empower developers worldwide with robust version control capabilities.

How to download the latest version of Git

The latest version of the Git client can be downloaded from the official site. To download Git version 2.41 for Windows, click here. To download Git version 2.41 for Linux/Unix, click here. To download Git version 2.41 for Mac OS, click here.