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

Breno Leitao
2026-04-01T14:47:35Z

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 |
+--------------+----------+----------+