Subject: Re: [PATCH net-next v3] page_pool: Add page_pool_release_stalled tracepoint

From: Jakub Kicinski <[email-masked]>
Date: Mon, 19 Jan 2026 08:43:10 -0800

On Mon, 19 Jan 2026 10:54:13 +0100 Jesper Dangaard Brouer wrote:
> On 19/01/2026 09.49, Leon Hwang wrote:
> >> My input here is the least valuable (since one may expect the person
> >> who added the code uses it) - but FWIW yes, we do use the PP stats to
> >> monitor PP lifecycle issues at Meta. That said - we only monitor for
> >> accumulation of leaked memory from orphaned pages, as the whole reason
> >> for adding this code was that in practice the page may be sitting in
> >> a socket rx queue (or defer free queue etc.) IOW a PP which is not
> >> getting destroyed for a long time is not necessarily a kernel issue.
> >>  
> 
> What monitoring tool did production people add metrics to?
> 
> People at CF recommend that I/we add this to prometheus/node_exporter.
> Perhaps somebody else already added this to some other FOSS tool?
> 
> https://github.com/prometheus/node_exporter

We added it to this:

  https://github.com/facebookincubator/dynolog

But AFAICT it's missing from the open source version(?!)

Luckily ynltool now exists so one can just plug it into any monitoring
system that can hoover up JSON:

  ynltool -j page-pool stats