US 12,430,210 B2
Managing changes to metadata in a data storage system
Dror Zalstein, Givatayim (IL); Vladimir Shveidel, Pardes-Hana (IL); and Jenny Derzhavetz, Raanana (IL)
Assigned to Dell Products L.P., Round Rock, TX (US)
Filed by Dell Products L.P., Round Rock, TX (US)
Filed on Mar. 23, 2023, as Appl. No. 18/188,568.
Prior Publication US 2024/0320098 A1, Sep. 26, 2024
Int. Cl. G06F 11/14 (2006.01); G06F 11/07 (2006.01); G06F 11/20 (2006.01)
CPC G06F 11/1435 (2013.01) [G06F 11/0793 (2013.01); G06F 11/2056 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A method comprising:
maintaining, in a persistent memory of a data storage system, a metadata change log, wherein the metadata change log is searchable and stores metadata changes that are to be applied to data storage system metadata that is stored in non-volatile data storage devices of the data storage system; and
adding a plurality of new metadata changes to the metadata change log, by:
storing the new metadata changes into the persistent memory within a memory pool for the metadata change log, wherein the memory pool for the metadata change log comprises a portion of the persistent memory from which the metadata change log is allocated,
storing, into a transaction entry located in the persistent memory within a memory pool for transaction entries, a plurality of structural modifications to the metadata change log that are needed to add the new metadata changes to the metadata change log, by storing, for each one of the structural modifications, i) an offset of a null pointer within the memory pool for the metadata change log and ii) a pointer to a location of a respective one of the new metadata changes within the persistent memory, wherein the null pointer is replaced by the pointer to the location of the respective one of the new metadata changes when the transaction entry is processed, and wherein the memory pool for transaction entries comprises a portion of the persistent memory from which transaction entries are allocated that is separately located from the portion of the persistent memory from which the metadata change log is allocated, and
processing the transaction entry to perform the structural modifications to the metadata change log stored in the transaction entry.