Patent attributes
A cloud-native global file system in which a local filer creates objects and forward them to a cloud-based object store is augmented to include a reshapable caching scheme for the local filer. Like striped caches, the approach uses a stripe, but the striping is implemented via a true RAID 0 (disk striping) rather than as a striped LV (logical volume) device. This approach allows for a “reshape” operation to convert from a n-way stripe set to a n+1-way stripe set. Preferably, a reshape involves redistributing each block on disk to its new calculated home. For example, going from a single disk to a two disk set would move every other block from disk 1 to disk 2, and rearrange the blocks on disk 1 to fill in the “holes”. Performance after the reshape matches that of a striped cache. In one embodiment, the cache is structured as a “degraded” RAID 4.