Linux's Local Cache For Network Filesystems Seeing Huge Speed-Up, Lower Memory Use

David Howells of Red Hat has been working to "massively overhaul" the code surrounding the kernel's local caching for network filesystems.

This big rework to fscache/cachefiles and friends not only lightens the code by around three thousand lines, but with now supporting async DIO to pass data to/from the cache, there is a "huge speed bonus" while also using less memory.

Besides modifying the core I/O interface and object lifecycle management for this local caching code, Howells has adapted the AFS file-system to make use of the new interface. He is still working on wiring up the reworked fscache code to NFS.

Those interested in all of the technical details can find them via this set of 61 patches now out for review. It will likely take some time to get this fscache code all squared away and the Linux network file-systems adapted for it, but long story short this improvement should be leading to a big speed-up and lower memory use once the code is ready to ship.