On Fri, Feb 28, 2020 at 12:13:54PM -0800, Vishnu Rangayyan wrote:
Hi,
I still see high (upto 30%) ksoftirqd cpu use with 4.19.101+ after these 2 back ports went in for 4.19.101
(had all 4 backports applied earlier to our tree):
commit f6783319737f28e4436a69611853a5a098cbe974 sched/fair: Fix insertion in rq->leaf_cfs_rq_list
commit 5d299eabea5a251fbf66e8277704b874bbba92dc sched/fair: Add tmp_alone_branch assertion
perf shows for any given ksoftirqd, with 20k-30k processes on the system with high scheduler load:
58.88% ksoftirqd/0 [kernel.kallsyms] [k] update_blocked_averages
Can we backport these 2 also, confirmed that it fixes this behavior of ksoftirqd.
commit 039ae8bcf7a5f4476f4487e6bf816885fb3fb617 upstream
commit 31bc6aeaab1d1de8959b67edbed5c7a4b3cdbe7c upstream
Do we also need bef69dd87828 ("sched/cpufreq: Move the
cfs_rq_util_change() call to cpufreq_update_util()") then?
--
Thanks,
Sasha
