Re: [PATCH] mm/vmstat: spread vmstat_update requeue across the stat interval

[Breno Leitao <leitao@debian.org>]

On Wed, Apr 01, 2026 at 06:57:50AM -0700, Breno Leitao wrote:
>   free_pcppages_bulk contention (KASAN):
>   +--------------+----------+----------+
>   | Metric       | No fix   | With fix |
>   +--------------+----------+----------+
>   | Contentions  |      872 |      117 |
>   | Total wait   | 199.43ms | 80.76ms  |
>   | Max wait     |   4.19ms | 35.76ms  |
>   +--------------+----------+----------+
> 
> Results without KASAN:
> 
>   free_pcppages_bulk contention (no KASAN):
>   +--------------+----------+----------+
>   | Metric       | No fix   | With fix |
>   +--------------+----------+----------+
>   | Contentions  |      240 |      133 |
>   | Total wait   |  34.01ms | 24.61ms  |
>   | Max wait     |   965us  |  1.35ms  |
>   +--------------+----------+----------+

Sorry, the Max wait time is inverted on both cases.

  free_pcppages_bulk contention (KASAN):
  +--------------+----------+----------+
  | Metric       | No fix   | With fix |
  +--------------+----------+----------+
  | Contentions  |      872 |      117 |
  | Total wait   | 199.43ms | 80.76ms  |
  | Max wait     |  35.76ms | 4.19ms   |
  +--------------+----------+----------+

Results without KASAN:

  free_pcppages_bulk contention (no KASAN):
  +--------------+----------+----------+
  | Metric       | No fix   | With fix |
  +--------------+----------+----------+
  | Contentions  |      240 |      133 |
  | Total wait   |  34.01ms | 24.61ms  |
  | Max wait     |   1.35ms |   965us  |
  +--------------+----------+----------+