[PATCH 0/8 V2] x86/intel_rdt: Intel Memory bandwidth allocation
From: Vikas Shivappa
Date: Fri Feb 17 2017 - 14:58:34 EST
Memory b/w allocation(MBA) is part of the Intel Resource Director
Technology (RDT). RDT helps monitor and share processor shared
resources. MBA helps enforce a limit on the memory bandwidth(b/w)
threads can use when they are scheduled. OS does the enforcement using
MSR(model specific register) interface and mapping the threads to
architecture specific CLOSids(class of service IDs).
The user interface is via the common resctrl fs for RDT features.
This can be used along with MBM (memory b/w monitoring) and cache
allocation to control and monitor the applications cache and memory
resources as per the QoS or other performance requirements. Use cases
could be large serverclusters, VM, clould and container based services
where the admin or orchestration tools can use this framework to
manage/allocate these processor shared resources like other memory/cpu
resources to provide QoS guarentees. Detailed use case examples are
documented in the 01/08 Documentation patch.
Patches are dependent on :
Thanks to Thomas for all the feed back and below are the changes as per
- Sent the RDT generic improvements patch series seperately
- Split the info file/validate apis as prep patches to MBA
- Fixed a lot of coding convention issues, variable initializations,
and removing unnecessary allocations etc.
- Changed the hotcpu handling for CLOS/RMID to zero the CLOSid/RMID when
cpu is offlined.
- Changed some naming conventions.
- Changed the interface to show the bandwidth percentage that can be
requested rather than showing h/w specific delay values which do not map
to a particular b/w percentage in non-linear scale
[PATCH 1/8] Documentation, x86: Documentation for Intel Mem b/w
[PATCH 2/8] x86/intel_rdt/mba: Generalize the naming to get ready for
[PATCH 3/8] x86/intel_rdt/mba: Memory b/w allocation feature detect
[PATCH 4/8] x86/intel_rct/mba: Add MBA structures and initialize MBA
[PATCH 5/8] x86/intel_rdt: info file support for MBA prepare
[PATCH 6/8] x86/intel_rdt/mba: Add info directory files for MBA
[PATCH 7/8] x86/intel_rdt: schemata file support for MBA prepare
[PATCH 8/8] x86/intel_rdt/mba: Add schemata file support for MBA