Active Block I/O Scheduling System Publisher's description
from Werner Almesberger
ABISS is an extension for the Linux kernel that implements priorities for disk IO operations.
Apart from these guaranteed real-time (RT) streams, we also included multiple priorities for best-effort (BE) disk traffic.
The system consists of a framework that is added to the kernel, including an elevator implementing multiple priorities, with a policy and coordination unit implemented in user space. This approach ensures separation between the kernel infrastructure (the framework) and the policies (e.g. admission control) in user space.
The ABISS extensions are controlled through ioctls applied to files accessed through the regular POSIX API. A small library with wrapper functions shaped after stdio (abiss_fopen(), abiss_fread(), abiss_fwrite(), etc.) is available for applications preferring a higher-level API.
ABISS is still experimental. It can currently provide high priority for reading from a FAT, VFAT, ext2, and ext3 file system. Writing is always best-effort.
Only a framework for resource control exists. Therefore, the current implementation can enforce that an application conforms to the requested service, but it cannot make bandwidth guarantees. Furthermore, there are various sources of sporadic but significant delays in the kernel, which can affect the service obtained by an application.
What's New in This Release:
ï¿½ Updated to Linux 22.214.171.124.
ï¿½ The compatibility layer has been moved from a global handler into each ioctl in each filesystem supported by ABISS.
ï¿½ CFQ is now supported.
ï¿½ Power management and overlap handling have been disabled for this version.
System Requirements:No special requirements.
Program Release Status:
Program Install Support: Install and Uninstall