It's apparent that a number of distributions and their customers remain on long-term stable kernels. We are aware of the scalability problems and other bugs in NFSD in kernels between v5.4 and v6.1. To address the filecache and other scalability problems in those kernels, I'm preparing backported patches of NFSD fixes for several popular LTS kernels. These backports are destined for the official LTS kernel branches so that distributions can easily integrate them into their products. Once this effort is complete, Greg and Sasha will continue to be responsible for backporting NFSD-related fixes from upstream into the LTS kernels. --- I've pushed the NFSD backports to branches in this repo: https://git.kernel.org/pub/scm/linux/kernel/git/cel/linux.git If you are able, I encourage you to pull these, review them or try them out, and report any issues or successes. I'm currently using the NFS workflows in kdevops as the testing platform, but am planning to include other tests. LTS v5.15.y There has been one new report of problems with freezing NFSD threads in linux-5.15.y, which Neil tracked down and fixed. The patch must also be applied to nfsd-5.10.y. LTS v5.10.y I've continued to build out automated NFSD testing for this kernel and origin/linux-5.10.y. I plan to send this patch series to Greg and Sasha soon. You can find this series in the "nfsd-5.10.y" branch in the above repo. -- Chuck Lever