Hi Boris, On 12/6/24 8:31 AM, Tony Luck wrote: > Background > ---------- > > The resctrl filesystem supports a mount option that allows users to > specify a memory bandwidth limit in MiB/s for each domain of a CTRL_MON > group. The underlying implementation uses data collected from the local > memory bandwidth monitoring event for the CTRL_MON group and all of > its MON subgroups as input to a feedback loop that adjusts the memory > bandwidth allocation control percentage up or down to keep the group > within the limit set by the user. > > Problem statement > ----------------- > > Hard coding the local memory bandwidth monitoring event has the following > issues: > > 1) Some systems may support total memory bandwidth monitoring but > not local. The user cannot use this mount option on such systems. > > 2) For large workloads that span NUMA domains using local bandwidth > monitoring will not throttle jobs correctly. > > 3) Users may have a mix of large and small workloads and may want to > use different input events per CTRL_MON group. > > Solution > -------- > > A) Provide a new user interface to choose which event is used for each > CTRL_MON group. > > B) Allow systems that only support total memory bandwidth monitoring to > use total bandwidth event. > > Changes since v10: > Link: https://lore.kernel.org/all/20241122235832.27498-1-tony.luck@xxxxxxxxx/ > > Patch Change > ----- ------ > > 2 s/filesystm/filesystem/ > Reformat block comment above definition of mba_mbps_default_event using > more of 80 column width > > 3 s/Update_mba_bw()/update_mba_bw() > > Added Reinette's Reviewed-by tag to parts 2-8 Could you please consider this series for inclusion? > > N.B. v6.13-rc1 introduced a locking change in commit f1be1788a32e ("block: > model freeze & enter queue as lock for supporting lockdep") that throws > a lockdep splat when mounting the resctrl filesystem (with certain > CONFIG options). > > Proposed patches that fix this are here: > Link: https://lore.kernel.org/all/20241206111611.978870-2-ming.lei@xxxxxxxxxx/ > Link: https://lore.kernel.org/all/20241206111611.978870-3-ming.lei@xxxxxxxxxx/ > > This fix has been merged into v6.13-rc2. Thank you very much. Reinette
