New mount option may be used to choose a specific memory bandwidth monitoring event to feed the MBA Software Controller(mba_sc) feedback loop. Signed-off-by: Tony Luck <tony.luck@xxxxxxxxx> --- Documentation/arch/x86/resctrl.rst | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/Documentation/arch/x86/resctrl.rst b/Documentation/arch/x86/resctrl.rst index a6279df64a9d..a0c521db6786 100644 --- a/Documentation/arch/x86/resctrl.rst +++ b/Documentation/arch/x86/resctrl.rst @@ -35,7 +35,8 @@ about the feature from resctrl's info directory. To use the feature mount the file system:: - # mount -t resctrl resctrl [-o cdp[,cdpl2][,mba_MBps][,debug]] /sys/fs/resctrl + # mount -t resctrl resctrl [-o cdp[,cdpl2][,mba_MBps] \ + [,mba_MBps_event=[mbm_local_bytes|mbm_total_bytes]][,debug]] /sys/fs/resctrl mount options are: @@ -45,7 +46,12 @@ mount options are: Enable code/data prioritization in L2 cache allocations. "mba_MBps": Enable the MBA Software Controller(mba_sc) to specify MBA - bandwidth in MBps + bandwidth in MBps. Defaults to using MBM local bandwidth, + but will use total bandwidth on systems that do not support + local bandwidth monitoring. +"mba_MBps_event=[mbm_local_bytes|mbm_total_bytes]": + Enable the MBA Software Controller(mba_sc) with a specific + MBM event as input to the feedback loop. "debug": Make debug files accessible. Available debug files are annotated with "Available only with debug option". @@ -538,6 +544,12 @@ where as user can switch to the "MBA software controller" mode using a mount option 'mba_MBps'. The schemata format is specified in the below sections. +By default the software feedback mechanism uses measurement of local +memory bandwidth to make adjustments to throttling levels. If a system +is running applications with poor NUMA locality users may want to use +the "mba_MBps_event=mbm_total_bytes" mount option which will use total +memory bandwidth measurements instead of local. + L3 schemata file details (code and data prioritization disabled) ---------------------------------------------------------------- With CDP disabled the L3 schemata format is:: -- 2.41.0
