Removing cpu_load completely certainly makes things simpler, my worry is just how much was lost by doing it. I agree that cpu_load needs a cleanup, but I can't convince myself that just removing it completely and not having any longer term view of cpu load anymore is without any negative side-effects.
Hi Alex,
Have you followed this thread about load_idx and the interest of using them to use different average period ? https://lkml.org/lkml/2014/1/6/499
Yes, I hoped to use blocked load before. But I still can not figure out the correct usage of it. Or maybe we need more quick decay for blocked load? Or, maybe clean cpu_load is helpful to make room to reconsider this.
Vincent
{source, target}_load() are now instantaneous views of the cpu load, which means that they may change very frequently. That could potentially lead to more task migrations at all levels in the domain hierarchy as we no longer have the more conservative cpu_load[] indexes that were used at NUMA level.
Maybe some of the NUMA experts have an opinion about this?
In the discussions around V1 I think blocked load came up again as a potential replacement for the current cpu_load array. There are some issues that need to be solved around blocked_load first though.
Morten