Dragonflybsd 6.2 was first launched in January 2022, including amdgpu Linux kernel driver porting, hammer2 improvements, nvmm hypervisor porting, and other improvements. Dragonflybsd 6.2.2 was released this weekend. Various bug fixes were made on the basis of stable code base.
The 6.2 series provides hardware support for the type-2 hypervisor with nvmm, adds amdgpu driver, and has the experimental ability to remotely install hammer2 volumes, as well as many other changes.
Dragonflybsd 6.2.2 is mainly used to repair the hammer2 original file system used by the BSD operating system by default. The scope of repair of hammer2 includes solving the possible crash problem, and the error that deleted files are still sluggish before unmounting in the file system.
Dragonflybsd 6.2.2 also solves the possible readdir() contention problem in TMPFS, and there are many different kernel fixes. In addition, there are updated time zone data as maintenance updates.
Dragonfly belongs to the same kind of operating system as other BSD derived systems and Linux. It shares the ancestor code with other BSD operating systems. Dragonfly provides another possibility for BSD foundation, which is completely different from FreeBSD, NetBSD and OpenBSD series.
Dragonfly contains many useful features that distinguish it from other similar operating systems.
The most prominent is hammer, a modern high-performance file system with built-in image and historical access functions.
Virtual kernel provides the ability to run a complete kernel as a user process to manage resources or accelerate kernel development and debugging.
The dragonflybsd kernel uses several synchronization and locking mechanisms for SMP. Since the beginning of the project, most of the work has been carried out in this field. It deliberately simplifies the categories of some locks, makes more subsystems less prone to deadlocks, and rewrites almost all the original code bases with algorithms specially designed for SMP. All these bring a very stable and high-performance kernel that can effectively use all the CPU, memory and i/o resources.
Dragonflybsd has almost no bottleneck or lock contention in the kernel. Almost all operations can run concurrently on any number of CPUs. Over the years, VFS support infrastructure (namecache, vnode cache), user support infrastructure (uid, GID, process group, session), process and thread infrastructure, storage subsystem, network, user and kernel memory allocation and management, process fork, exec and exit/ teardown, time keeping, and all other aspects of kernel design have been rewritten with the goal of extreme SMP performance.
Dragonfly uses swap space to cache file system data and metadata, thus making unique use of the widespread presence of low-cost solid-state storage devices (SSDs). This feature is often referred to as "swap cache", which can greatly increase the workload of servers and workstations with a small hardware investment.
The dragonfly storage stack includes powerful, locally written AHCI and nvme drivers, which are partially implemented through the stable device name of devfs and the device mapper for reliable volume management and encryption.
Other functions that are particularly useful to system administrators are: a high-performance and scalable TMPFS implementation, an extremely efficient nullfs, which does not require internal replication of directory or file nodes, dntpd (NTP client) written natively uses full line interception and standard deviation summation to maintain highly accurate time, and DMA, It aims to provide low overhead mail services for system operators who do not need more extensive mail services such as postfix or sendmail.
Dragonfly uses the dports system to provide thousands of source code and binary applications. These functions, combined with more functions, make Dragonfly a modern, useful, friendly and familiar UNIX like operating system.
The list of more than 20 stable bug fixes that make up dragonflybsd 6.2.2 can be found in the submission list:
This stable version of dragonflybsd can be downloaded from dragonflybsd Org Download: