Optimizations & Performance Improvements For DM In Linux 3.19

Another one of the interesting early pull requests for the Linux 3.19 kernel is the Device Mapper changes.

Device Mapper, the kernel framework for mapping block devices into virtual block devices to be used for Linux software RAID, dm-crypt, LVM2, and other purposes, has seen some noteworthy improvements for this next Linux kernel cycle.

The Devie Mapper changes for Linux 3.19 include "significant DM thin-provisioning performance improvements" that were done to meet the needs of the Gluster distributed file-system. This should especially help out the performance of hardware RAID 6 devices too. Linux 3.19's Device Mapper also has optimizations in DM core and RCU dereference clean-ups, support for the new suspend/resume interface in DM core changes, DM cache discard improvements, DM cache multi-queue policy block promotion improvements, and various fixes.

Those big into using DM can find out more details via Mike Snitzer's pull request.