Embodiments are directed to managing data in a file system that includes a plurality of storage nodes and a plurality of storage volumes such that each storage node may be a compute instance provided by a cloud computing environment (CCE) and each storage volume may be based on blobs provided by the CCE. Write requests that include write data may be provided. A lowest range of addresses in the storage volume may be determined for storing the write data. Buckets may be determined based on the range of addresses and the write data assigned to the buckets. If portions of the buckets remain unassigned, other data may be provided from a cache volume or the blobs. The write data and the other data may be written to the portion of the blobs.