On 2020/2/21 下午11:47, Peter Zijlstra wrote: > On Fri, Feb 21, 2020 at 02:20:10PM +0000, Mel Gorman wrote: >> I fully acknowledge that this may have value for sysadmins and may be a >> good enough reason to merge it for environments that typically build and >> configure their own kernels. I doubt that general distributions would >> enable it but that's a guess. > > OTOH, many sysadmins seem to 'rely' on BPF scripts and other such fancy > things these days. > > ( of course, we have the open question on what happens when we break > one of those BPF 'important' scripts ... ) > > My main reservation with this patch is that it exposes, to userspace, an > ABI that is very hard to interpret and subject to implementation > details. > > So while it can be disabled; people who have it enabled might suddenly > complain when we change the meaning/interpretation/whatever of these > magic numbers. > > Michael; you seem to have ignored the tracepoint / BPF angle earlier in > this discussion; that is not something that could/would work for you? At very beginning I think these fancy stuff may consume too much resources them selves, so just as you said, ignored the possibility :-P But now I understand there is a big gap here, which require a much more general way to evaluate the NUMA platform, I'll try to follow this way see if there are any practical approach instead~ Regards, Michael Wang >