Dell Products Inc.

Christopher A Seibel

Vamsi K Vankamamidi

Andrew T Feld

Kamakshi Viswanadha

Christopher J Jones

Philippe Armangau

Vladimir Shveidel

James Vega Mccoy

In at least one embodiment, processing can include: receiving a write that writes content to a logical address; recording an entry for the write in a log; flushing the entry from the log; recording, in a metadata log, an update to a metadata page; flushing the update from the metadata log; generating an updated version of the metadata page including the update; staging the updated version of the metadata page to a staging area of a plurality of partitions, comprising: selecting a partition of the staging area based on: a partition owner of the partition, a page owner of the metadata page, a type of the metadata page, and a second type of the first partition; selecting a zone of the partition based on a processing node performing said staging; and writing the updated version of the metadata page to the zone of the partition.

Techniques for staging updated metadata pages based on owner and metadata

A method, computer program product, and computing system for receiving a metadata page for storage within a log-structured metadata store. An entry may be generated within a translation table page of a translation table within the log-structured metadata store, wherein each entry of a plurality of entries within the translation table page is associated with a separate metadata page. One or more metadata page deltas for the metadata page may be recorded in the log-structured metadata store. The one or more metadata page deltas for the metadata page may be flushed to a persistent memory storage. In response to flushing the one or more metadata page deltas for the metadata page, the entry within the translation table page that is associated with the metadata page may be updated without accessing any other entry within the translation table page associated with other metadata pages.

System and method for managing metadata access in a log-structured system

In at least one embodiment, processing can include: receiving, from a client, a request to access a metadata (MD) page, wherein the request specifies a lock type denoting a particular level of access to the MD page that is being requested by the request; and responsive to receiving the request, performing first processing including: locking the MD page and a corresponding translation table entry Efor the MD page in accordance with the lock type denoting a particular level of access being requested, wherein Emaps a logical address LAof the MD page to a physical storage or location PAon non-volatile storage where the MD page is stored; and subsequent to said locking, returning a response including the MD page to the client.

Techniques for destaging translation table updates and accessing translation table entries in a log-structured system

In at least one embodiment, processing can include: storing a metadata page at new physical location PA2 on non-volatile storage; and recording in a translation table (TT) log, a TT update to a mapping entry E1 of the TT, wherein the TT update updates E1 of the TT to map a logical address LA1 of the metadata page to PA2. Recording can include querying a unified hash table (UHT) in accordance with LA1 to determine whether the UHT includes a UHT entry mapping LA1 to a corresponding physical address or location of where the MD page is stored on non-volatile storage. Responsive to determining that the UHT includes a UHT entry for LA1, processing can include: determining whether the UHT entry is a cache type. If the UHT entry is the cache type, processing can include converting the UHT entry to a delta type entry of the TT log.

Techniques using a unified cache for storing and accessing translation table entries and updates

In at least one embodiment, processing can include: recording, in a metadata (MD) log, a metadata (MD) update to a MD page having a logical address LA1; flushing MD updates, including the MD update, from the MD log; applying at least the MD update to the MD page to generate an updated version; storing the updated version of the MD page at a storage location PA2 different from a first location of the MD page prior to updating; recording, in a translation table (TT) log, a TT update that updates entry E1 of a TT to map LA1 of the MD page to PA2 rather than the first location; flushing TT updates from the TT log; applying at least the TT update to the TT to generate an updated version; and storing the updated TT version at a storage location different from a prior location of the TT prior to updating.

Log-structured architecture for metadata

Techniques for providing an adaptive approach to prefetching data for sequential read streams in a storage system. The techniques can include performing prefetch operations for a sequential read stream in accordance with a prefetch distance and a prefetch size, counting or otherwise keeping track of occurrences of failure scenarios in the prefetch operations while servicing the sequential read stream, and modifying or adjusting one of the prefetch distance and the prefetch size based on the occurrences of the respective failure scenarios. In this way, host input/output (IO) latency can be reduced, and IO bandwidth can be increased, in the servicing of sequential read streams by the storage system.

Growing community of inventors

Walpole, MA, United States of America

Christopher A Seibel