Extent reads at random offsets by synthesizing extents to leverage sequential restore performance

A system for improving read performance of a file using data pre-fetches in a client-server network, comprising:

• a server hosting a filesystem storing data in storage for an application executed in the network;
• a network client hosting the application;
• a backup processing component obtaining extent information for delta changes between a first generation backup file and a second generation backup file;
• a data storage server running a Data Domain filesystem (DDFS), and wherein the client comprises a DDBoost client;
• a storage storing the extent information in a storage comprising part of a deduplication backup process executed by the data storage server, wherein the extent information is returned to the backup process for patching into a target file using a DDBoost application programming interface (API) to read the new synthesized file, wherein the API includes a read buffer with offset/length extent information of data of the new synthesized file;
• and
• a server component receiving, from the network client, an instruction to create a new synthesized file corresponding to the extent information, and creating, upon receiving this instruction, a new synthesized file comprising extents of the extent information as contiguous data that can be read sequentially to leverage the benefits of the pre-fetches.