US 12,455,859 B2
Extent restore performance using smart prefetching
Nitin Madan, Cupertino, CA (US); Kedar Godbole, Pune (IN); Srikant Viswanathan, Pune (IN); and Bhimsen Bhanjois, Fremont, CA (US)
Assigned to Dell Products L.P., Round Rock, TX (US)
Filed by Dell Products L.P., Round Rock, TX (US)
Filed on Aug. 3, 2023, as Appl. No. 18/364,625.
Prior Publication US 2025/0045248 A1, Feb. 6, 2025
Int. Cl. G06F 16/172 (2019.01); G06F 11/14 (2006.01)
CPC G06F 16/172 (2019.01) [G06F 11/1469 (2013.01); G06F 2201/84 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A computer-implemented method for improving read performance of a file using data pre-fetches, comprising:
encoding an extent map identifying valid data of the file as extents, wherein the file is a holey file comprising the valid data interspersed with one or more holes constituting invalid data;
storing the extent map in a network client executing an application, wherein the application produces a read request to access the file from storage, wherein extent map comprises a recipe consisting of a sequence of offsets, with each offset defining a corresponding extent;
transferring, upon the read request, the extent map to a filesystem storing the file;
bringing, in the filesystem, the extents from the extent map into memory ahead of the read request;
calculating, using the recipe, extent-aware prefetch offsets that skip over the one or more holes so that the prefetch offsets always fall within an extent of valid data of the file; and
generating pre-fetches of data on the file using the extent-aware prefetch offsets.