From: Bing Niu <bing....@intel.com> This series is to introduce RDT memory bandwidth allocation support by extending current virresctrl implementation.
The Memory Bandwidth Allocation (MBA) feature provides indirect and approximate control over memory bandwidth available per-core. This feature provides a method to control applications which may be over-utilizing bandwidth relative to their priority in environments such as the data-center. The details can be found in Intel's SDM 17.19.7. Kernel supports MBA through resctrl file system same as CAT. Each resctrl group have a MB parameter to control how much memory bandwidth it can utilize in unit of percentage. In this series, MBA is enabled by enhancing existing virresctrl implementation. The policy employed for MBA is similar with CAT: The sum of each MBA group's bandwidth dose not exceed 100%. The enhancement of virresctrl include two parts: Part 1: Add two new structures virResctrlInfoMB and virResctrlAllocMB for collecting host system MBA capability and domain memory bandwidth allocation. Those two structures are the extension of existing virResctrlInfo and virResctrlAlloc. With them, virresctrl framework can support MBA and CAT concurrently. Each virResctrlAlloc represent a resource allocation including CAT, or MBA, or CAT&MBA. The policy of MBA is that: total memory bandwidth of each resctrl group, created by virresctrl, does not exceed to 100%. Part 2: On XML part, add new elements to host capabilities query and domain allocation to support memory bandwidth allocation. ---------------------------------------------------------------------------------------------- For host capabilities XML, new XML format like below example, <host> ..... <memory> <node id='0' cpus='0-19'> <control granularity='10' min ='10' maxAllocs='8'/> </node> </memory> </host> granularity --- memory bandwidth granularity min --- minimum memory bandwidth allowed maxAllocs --- maximum concurrent memory bandwidth allocation allowed. ---------------------------------------------------------------------------------------------- For domain XML, new format as below example <domain type='kvm' id='2'> ...... <cputune> ...... <shares>1024</shares> <memorytune vcpus='0-1'> <node id='0' bandwidth='20'/> </memorytune> </cputune> ...... </domain> id --- node where memory bandwidth allocation will happen bandwidth --- bandwidth allocated in percentage ---------------------------------------------------------------------------------------------- Changelog: v1->v2: Jano's comment: 1. put renaming parts into separated patches. 2. set the initial return value as -1. 3. using full name in structure definition. 4. do not use VIR_CACHE_TYPE_LAST for memory bandwidth allocation formatting. Pavel's comment: 1. add host capabilities XML for memory bandwidth allocation. 2. do not mix use cachetune section in XML for memory bandwidth allocation in domain XML. define a dedicated one for memory bandwidth allocation. Bing Niu (5): util: Rename and packing parts of virresctrl util: Add memory bandwidth support to resctrl conf: rename cachetune to restune conf: Introduce cputune/memorytune to support memory bandwidth allocation conf: add memory bandwidth allocation capability of host src/conf/capabilities.c | 112 +++++++++++ src/conf/capabilities.h | 11 ++ src/conf/domain_conf.c | 304 ++++++++++++++++++++++++++--- src/conf/domain_conf.h | 10 +- src/libvirt_private.syms | 4 +- src/qemu/qemu_process.c | 18 +- src/util/virresctrl.c | 496 ++++++++++++++++++++++++++++++++++++++++++++--- src/util/virresctrl.h | 35 +++- 8 files changed, 918 insertions(+), 72 deletions(-) -- 2.7.4 -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list