With NFSv4.2 is the server-side copy (SSC) functionality with the Linux 5.5 kernel's NFS client-side support for that support in allowing "inter" copy offloads between different NFS servers.

When it comes to the storage/file-system changes with the in-development Linux 5.5 kernel one of the most prominent end-user-facing changes is more robust RAID1 for Btrfs with the ability to have three or four copies of the data rather than just two copies, should data safety be of utmost importance and concerned over the possibility of two disks in an array failing.

The Flash-Friendly File-System continues to be refined and with the forthcoming Linux 5.5 kernel are more improvements albeit largely bug fixes.

The XFS file-system is seeing a large number of changes for the in-development Linux 5.5 kernel.

The Linux 5.5 block changes landed earlier this week with a wide variety of driver and core improvements. There are some I/O optimizations to make the pull exciting as well as the NVMe HWMON drive temperature reporting integration.

While EXT4 is the most common Linux file-system among distributions and is quite mature at this stage, it does continue seeing noteworthy improvements every so often with new kernel releases. With Linux 5.5 there are more notable improvements on deck.

David Sterba sent in his pull request early of the Btrfs file-system changes that are ready for merging into the Linux 5.5 merge window next week.

For the past four years going back to Linux 4.4 has been EXT4 native file-system encryption making use of the kernel's FSCRYPT framework that is shared between several file-systems. That support has continued to improve with time and with Linux 5.5 another limitation will be dropped.

While Linux 5.4 is rolling out in about two weeks, the out-of-tree Reiser4 file-system has just been updated for Linux 5.3 support.

Taking place this past week in San Francisco was the annual OpenZFS Developer Summit. As usual, Matthew Ahrens as the co-founder of Sun ZFS and current OpenZFS contributor at Delphix talked about the state of the open-source ZFS efforts in his keynote.

Among other EXT4 file-system changes en route for the upcoming Linux 5.5 kernel is a new direct I/O read implementation.

Fscrypt as the file-system encryption framework used by the likes of EXT4 and F2FS for offering native encryption capabilities continues being improved upon, especially by the likes of Google that are making use of it for Android devices.

Similar to the transparent file-system compression that has been available on the likes of Btrfs and ZFS for years, the Flash-Friendly File-System (F2FS) is also in the process of receiving native compression support.

Longtime FUSE developer Miklos Szeredi of Red Hat has been working on a new "FUSE2" FUSE kernel driver for implementing file-systems in user-space.

ZFS On Linux 0.8.2 is out with fixes in order to provide compatibility with the brand new Linux 5.3 stable kernel while retaining support still going back to the Linux 2.6.32 days.

VirtIO-FS as a better approach for sharing folders/files with guest VMs is set to debut in Linux 5.4.

Sent in and already landed on Monday were the PCI changes for Linux 5.4 and includes an interesting feature addition.

Added to the device mapper (DM) code with the Linux 5.4 kernel is an interesting addition that benefits those wanting to carry out some interesting use-cases around remote replication of block devices.

While most of the other Linux file-systems are seeing mostly mundane changes for the Linux 5.4 feature work, the F2FS activity is fairly notable.

The OpenZFS file-system could soon be seeing better data deduplication support.

Like the mostly mundane Btrfs and XFS changes with the Linux 5.4 merge window, the EXT4 file-system activity is mostly focused on fixes too but also new debugging ioctls.

The Linux 5.4 block subsystem changes brings the new blk-iocost model.

The mature XFS and Btrfs file-systems continue seeing more fixes and cleaning with the now in-development Linux 5.4 kernel.

In addition to submitting the FS-VERITY file authentication code for Linux 5.4, Google's Eric Biggers has sent out his big update to the fscrypt file encryption framework for this next kernel revision.

While the upcoming Linux 5.4 kernel cycle is finally bringing a driver for Microsoft exFAT file-system read/write support, it's dated on an old Samsung code drop that has seen little public work over the years. Since queued for staging-next, there has been a big uptick in clean-ups and other activity, but there also exists another alternative out-of-tree exFAT Linux driver.

A Phoronix reader pointed out recent patches by a SUSE engineer working on support for mounting root file-systems over SMB (Samba).

The EXT4 case-insensitive lookup optimization added to the file-system with the current Linux 5.3 cycle has been ported to the Flash-Friendly File-System (F2FS) for the upcoming Linux 5.4.

A Phoronix reader recently pointed out a little known kernel tunable option to adjust the number of I/O polling queues for NVMe solid-state drives that can potentially help improve the performance/latency. Here are some benchmarks from the NVMe poll_queues option.

Linux 5.4 will be a big kernel on the file-system front as in addition to introducing the new VirtIO-FS and exFAT file-system support, Huawei's EROFS file-system will be graduating from staging.

In addition to the initial exFAT driver landing for Linux 5.4, also slated to land for this next kernel cycle is the VirtIO-FS file-system driver.