US 12,306,721 B2
Pre-filter check for compressibility using stored compression factors to improve reads in a deduplication file system
Donna Barry Lewis, Holly Springs, NC (US); Nitin Madan, Cupertino, CA (US); 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 Jul. 26, 2023, as Appl. No. 18/359,427.
Prior Publication US 2025/0036530 A1, Jan. 30, 2025
Int. Cl. G06F 16/00 (2019.01); G06F 11/14 (2006.01); G06F 16/174 (2019.01)
CPC G06F 11/1453 (2013.01) [G06F 11/1469 (2013.01); G06F 16/1744 (2019.01); G06F 2201/84 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A computer-implemented method of optimizing compression for reads in a restore path of a client-side inline deduplication file system, comprising:
defining an extent covering data segments for which compression ratio statistics are calculated;
calculating a respective compression ratio for each data segment in the defined extent, wherein the compression ratio of a data segment is calculated by dividing an uncompressed size of the data segment by a compressed size of the data segment;
associating each unique compression ratio with a corresponding index value;
storing each compression ratio and associated corresponding index value in an array;
appending the array as extended file attribute to the data segments;
using the indexed compression ratio by a backup server to determine whether or not to apply compression to the data segments in a restore path sending the data segments from the backup server, and wherein an index value is calculated by dividing an offset by a size of the extent minus 1; and
applying, in a deduplication process of the backup server, the compression to the data segments to reduce an amount of data processed during the reads by the client-side deduplication file system.