On 6/9/25 10:52 AM, Vlastimil Babka wrote: > On 6/9/25 10:31 AM, Ritesh Harjani (IBM) wrote: >> Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx> writes: >> >>> On 2025/6/9 15:35, Michal Hocko wrote: >>>> On Mon 09-06-25 10:57:41, Ritesh Harjani wrote: >>>>> >>>>> Any reason why we dropped the Fixes tag? I see there were a series of >>>>> discussion on v1 and it got concluded that the fix was correct, then why >>>>> drop the fixes tag? >>>> >>>> This seems more like an improvement than a bug fix. >>> >>> Yes. I don't have a strong opinion on this, but we (Alibaba) will >>> backport it manually, >>> >>> because some of user-space monitoring tools depend >>> on these statistics. >> >> That sounds like a regression then, isn't it? > > Hm if counters were accurate before f1a7941243c1 and not afterwards, and > this is making them accurate again, and some userspace depends on it, > then Fixes: and stable is probably warranted then. If this was just a > perf improvement, then not. But AFAIU f1a7941243c1 was the perf > improvement... Dang, should have re-read the commit log of f1a7941243c1 first. It seems like the error margin due to batching existed also before f1a7941243c1. " This patch converts the rss_stats into percpu_counter to convert the error margin from (nr_threads * 64) to approximately (nr_cpus ^ 2)." so if on some systems this means worse margin than before, the above "if" chain of thought might still hold. > >> -ritesh >
