Filesystem with isolated independent filesets

A computer program product for managing a filesystem, the filesystem including a pool of data blocks, and further including a pool of index blocks, the computer program product comprising a non-transitory computer-readable storage medium having program instructions embodied therewith, the program instructions executable by a computer to cause the computer to:

• identify within the pool of data blocks a plurality of non-overlapping subpools of data blocks, the plurality of subpools of data blocks including a first subpool of data blocks and further including a second subpool of data blocks;
• identify within the pool of index blocks a plurality of non-overlapping subpools of index blocks, the plurality of subpools of index blocks including a first subpool of index blocks and further including a second subpool of index blocks, wherein the first subpool of data blocks is non-overlapping from the second subpool of data blocks, and wherein the first subpool of index blocks is non-overlapping from the second subpool of index blocks, and wherein each of the first and second subpools of data blocks and the first and the second subpools of index blocks are arranged in isolated, independent file sets;
• mount a first file group within a global namespace on a first mount point on the filesystem;
• mount a second file group within the global namespace on a second mount point on the filesystem, wherein the first mounted file group and the second mounted file group are configured to undergo filesystem checks independently of each other, the filesystem checks performed in response to corruption within at least one of the first mounted file group and the second mounted file group;
• allocate the first subpool of data blocks to the first mounted file group, wherein the allocating the first subpool of data blocks to the first mounted file group comprises transferring control of the first subpool of data blocks from the filesystem to the first file group;
• allocate the first subpool of index blocks to the first mounted file group, wherein the allocating the first subpool of index blocks to the first mounted file group comprises transferring control of the first subpool of index blocks from the filesystem to the first file group, wherein the first mounted file group includes a first set of files, the first set of files having a first set of file data and further having a first set of file metadata;
• populate the first subpool of data blocks with the first set of file data;
• populate the first subpool of index blocks with the first set of file metadata;
• allocate the second subpool of data blocks to the second mounted file group;
• allocate the second subpool of index blocks to the second mounted file group, wherein the second mounted file group includes a second set of files, the second set of files having a second set of file data and further having a second set of file metadata;
• populate the second subpool of data blocks with the second set of file data;
• populate the second subpool of index blocks with the second set of file metadata;
• operate the first mounted file group at a first redundant array of independent disks (RAID) level while operating the second mounted file group at a second RAID level;
• and
• perform, in response to corruption resulting from double allocation of at least one data block within the first mounted file group, a filesystem check on the first mounted file group without contemporaneously performing the filesystem check on the second mounted file group.

A system for managing a filesystem, the filesystem including a pool of data blocks and further including a pool of index blocks, the system comprising one or more computer processor circuits configured to perform a method comprising:

• identifying within the pool of data blocks a plurality of non-overlapping subpools of data blocks, the plurality of subpools of data blocks including a first subpool of data blocks and further including a second subpool of data blocks;
• identifying within the pool of index blocks a plurality of non-overlapping subpools of index blocks, the plurality of subpools of index blocks including a first subpool of index blocks and further including a second subpool of index blocks, wherein the first subpool of data blocks is non-overlapping from the second subpool of data blocks, and wherein the first subpool of index blocks is non-overlapping from the second subpool of index blocks, and wherein each of the first and second subpools of data blocks and the first and the second subpools of index blocks are arranged in isolated, independent file sets;
• mounting a first file group within a global namespace on a first mount point on the filesystem;
• mounting a second file group within the global namespace on a second mount point on the filesystem, wherein the first mounted file group and the second mounted file group are configured to undergo filesystem checks independently of each other, the filesystem checks performed in response to corruption within at least one of the first mounted file group and the second mounted file group;
• allocating the first subpool of data blocks to the first mounted file group;
• allocating the first subpool of index blocks to the first mounted file group;
• allocating the second subpool of data blocks to the second mounted file group;
• allocating the second subpool of index blocks to the second mounted file group;
• establishing a corruption isolation barrier between a first virtual machine having a first virtual hard drive and a second virtual machine having a second virtual hard drive by storing data of the first virtual hard drive within the first subpool data blocks allocated to the first mounted file group, further by storing metadata of the first virtual hard drive within the first subpool of index blocks allocated to the first mounted file group, further by storing data of the second virtual hard drive within the second subpool of data blocks allocated to the second mounted file group, and further by storing metadata of the second virtual hard drive with the second subpool of index blocks allocated to the second mounted file group;
• operating the first mounted file group at a first redundant array of independent disks (RAID) level while operating the second mounted file group at a second RAID level;
• and
• performing, in response to corruption resulting from double allocation of at least one data block within the first mounted file group, a filesystem check on the first mounted file group without contemporaneously performing the filesystem check on the second mounted file group.