The code base of the Linux kernel, which serves as the foundation for version 6.15, has incorporated a set of changes aimed at optimizations that significantly enhance the performance of network operations in various situations:
- The GRO (Generic Receive Offload) optimization, which combines multiple small packets into a larger one, is now utilized when switching packet processing to another CPU (for load balancing) while using the XDP (eXpress Data Path) subsystem, allowing packet processing at the network driver level before they are sent to the network stack. The performance gain in TCP stream processing from this optimization can reach up to twofold.
- Under heavy load, the performance of the connect() function has increased by up to two times by replacing spin-locking with the RCU (Read-Copy-Update) synchronization mechanism when searching for records containing connection information (source and target ports). Additionally, hash optimization has provided a further performance boost of 229%. an IP address The implementation of MPTCP (Multipath TCP), an extension of the TCP protocol for enabling packet delivery simultaneously over multiple routes through different network interfaces tied to different IP addresses, has been accelerated. In single-stream mode, MPTCP has been sped up by 29%.
- In netfilter, when a socket exists, route lookups in the FIB (Forwarding Information Base) have been discontinued. Thanks to this optimization, performance has increased by 20%.
- UDP performance under flood conditions has been enhanced by 10% by eliminating unnecessary operations with the sk_tsflags structure when receiving packets.
- Furthermore, in the upcoming Linux kernel 6.15, a change has been approved for the exFAT filesystem driver that speeds up file deletion operations. Previously, the exFAT driver individually sent 'discard' requests to storage for each released cluster of the deleted file. The optimized version groups these requests, resulting in a reduction of the deletion time for a test file of 80 GB from 286 seconds to 1.6 seconds.
Release of the Restic backup system 0.18. Attack on CDC
Source: opennet.ru
