Abstract: Systems and methods for reducing read application in a virtual storage system are provided. According to one embodiment, heuristic data may be tracked and utilized in real-time by a file system of the virtual storage system at the level of granularity of a volume, thereby allowing a fast path flag to be enabled/disabled at a volume level during various phases of operation of a workload. The heuristic data for a given volume may be indicative of a correlation between (i) data blocks stored on the given volume being located within a compressible zone of a zoned checksum scheme and (ii) the respective data blocks containing compressed data and a corresponding checksum. Based on the heuristic data, read requests may be selectively directed to the read path (e.g., a fast path or a slow path) expected to mitigate read amplification when data compression is enabled for a zoned checksum scheme.

Abstract: Systems and methods for reducing read application in a virtual storage system are provided. According to one embodiment, read amplification is reduced when AZCS compression is being utilized by avoiding restarting of a read process via a slow path via a RAID layer of the virtual storage system when a data block associated with a read request and obtained via a first fast path read has been found not to be compressed. Instead, a second fast path read may be performed to obtain the corresponding checksum. Alternatively, or additionally, heuristics may be used to predict the odds of the data block being compressed. For example, when information encoded within a PVBN of the data block that identifies the PVBN as being within a compressed AZCS zone has shown to be sufficiently/insufficiently predictive of the data block being compressed, then a flag may be set to enable/disable fast path reads.