Lines Matching refs:bandwidth
41 bandwidth in MBps
121 Memory bandwidth(MB) subdirectory contains the following files
125 The minimum memory bandwidth percentage which
129 The granularity in which the memory bandwidth
133 available bandwidth control steps are:
144 request different memory bandwidth percentages:
150 bandwidth percentages are directly applied to
364 Memory bandwidth Allocation and monitoring
367 For Memory bandwidth resource, by default the user controls the resource
368 by indicating the percentage of total memory bandwidth.
370 The minimum bandwidth percentage value for each cpu model is predefined
371 and can be looked up through "info/MB/min_bandwidth". The bandwidth
373 be looked up at "info/MB/bandwidth_gran". The available bandwidth
377 The bandwidth throttling is a core specific mechanism on some of Intel
378 SKUs. Using a high bandwidth and a low bandwidth setting on two threads
380 low bandwidth (see "thread_throttle_mode").
382 The fact that Memory bandwidth allocation(MBA) may be a core
383 specific mechanism where as memory bandwidth monitoring(MBM) is done at
385 via the MBA and then monitor the bandwidth to see if the controls are
388 1. User may *not* see increase in actual bandwidth when percentage
391 This can occur when aggregate L2 external bandwidth is more than L3
392 external bandwidth. Consider an SKL SKU with 24 cores on a package and
393 where L2 external is 10GBps (hence aggregate L2 external bandwidth is
394 240GBps) and L3 external bandwidth is 100GBps. Now a workload with '20
395 threads, having 50% bandwidth, each consuming 5GBps' consumes the max L3
396 bandwidth of 100GBps although the percentage value specified is only 50%
397 << 100%. Hence increasing the bandwidth percentage will not yield any
398 more bandwidth. This is because although the L2 external bandwidth still
399 has capacity, the L3 external bandwidth is fully used. Also note that
402 2. Same bandwidth percentage may mean different actual bandwidth
405 For the same SKU in #1, a 'single thread, with 10% bandwidth' and '4
406 thread, with 10% bandwidth' can consume upto 10GBps and 40GBps although
407 they have same percentage bandwidth of 10%. This is simply because as
408 threads start using more cores in an rdtgroup, the actual bandwidth may
409 increase or vary although user specified bandwidth percentage is same.
412 resctrl added support for specifying the bandwidth in MBps as well. The
414 Controller(mba_sc)" which reads the actual bandwidth using MBM counters
415 and adjust the memory bandwidth percentages to ensure::
417 "actual bandwidth < user specified bandwidth".
419 By default, the schemata would take the bandwidth percentage values
451 Memory bandwidth Allocation (default mode)
459 Memory bandwidth Allocation specified in MBps
462 Memory bandwidth domain is L3 cache.
669 for cache bit masks, minimum b/w of 10% with a memory bandwidth
774 50% of the L3 cache on socket 0, and 50% of memory bandwidth on socket 0
780 to the "top" 50% of the cache on socket 0 and 50% of memory bandwidth on
789 also get 50% of memory bandwidth assuming that the cores 4-7 are SMT