NFS Lands Initial Support For Directory Delegations In Linux 6.19
The Network File-System (NFS) client changes were merged today for the Linux 6.19 kernel with the most notable feature addition being initial support for basic directory delegations.
NFS directory delegations allow for an efficiency win by knowing if nobody else modified the directory on the NFS server then there are some re-validation shortcuts than can be subsequently taken by the NFS client. This work was pursued by Oracle to allow for better NFS efficiency when knowing a particular directory hasn't changed from underneath the client. For Linux 6.19 the directory delegation is hooked up for ACCESS, CREATE, UNLINK, and RENAME operations.
The directory_delegations module parameter is added to the NFS module for disabling the directory delegation feature if desired for debugging / testing / performance evaluation purposes.
Besides this basic directory delegation support, the NFS client merge brings code clean-ups to the SunRPC back channel code and various bug fixes throughout.
Merged last week meanwhile was the NFSD server changes for Linux 6.19 that add an option to disable I/O caching for that Linux 6.18 feature is now extended to include using direct I/O. The intent there is on further reducing the memory footprint consumed by NFS clients when accessing large data sets. Plus NFSD saw various minor optimizations and other code improvements.
NFS directory delegations allow for an efficiency win by knowing if nobody else modified the directory on the NFS server then there are some re-validation shortcuts than can be subsequently taken by the NFS client. This work was pursued by Oracle to allow for better NFS efficiency when knowing a particular directory hasn't changed from underneath the client. For Linux 6.19 the directory delegation is hooked up for ACCESS, CREATE, UNLINK, and RENAME operations.
The directory_delegations module parameter is added to the NFS module for disabling the directory delegation feature if desired for debugging / testing / performance evaluation purposes.
Besides this basic directory delegation support, the NFS client merge brings code clean-ups to the SunRPC back channel code and various bug fixes throughout.
Merged last week meanwhile was the NFSD server changes for Linux 6.19 that add an option to disable I/O caching for that Linux 6.18 feature is now extended to include using direct I/O. The intent there is on further reducing the memory footprint consumed by NFS clients when accessing large data sets. Plus NFSD saw various minor optimizations and other code improvements.