RE: [PATCH] tracing: report buffer memory in /proc/meminfo

[gao xu]

> On Mon, 10 Aug 2026 12:22:43 +0100
> "Lorenzo Stoakes (ARM)" <ljs@xxxxxxxxxx> wrote:
> 
> > On Mon, Aug 10, 2026 at 12:52:38PM +0200, David Hildenbrand (Arm) wrote:
> > > On 8/10/26 11:40, Xiang Gao wrote:
> > > > Report the data capacity of all ftrace ring buffers through a new
> > > > Ftrace field in /proc/meminfo. Include the main and snapshot
> > > > buffers of the global trace array and all tracing instances, while
> > > > leaving ring-buffer metadata accounted for by Slab.
> > >
> > > why? :)
> > >
> > > To report a handful of KiB as in your example below? Doesn't sound
> > > super helpful TBH.
> >
> > Yeah I think we need to stop with all the proposed additions to
> > /proc/meminfo :)
> >
> > Also something like this where you are making a change in output that
> > it is just your opinion that it is useful should be an RFC to see what
> > the community thinks first.
> 
> Agreed. This doesn't belong in the meminfo. If you want memory statistics for
> tracing, I may be OK if you add a "total_memory_kb" file in the
> /sys/kernel/tracing/trace_stats/ directory.
Would it be possible to include this info in show_mem()?
This would be helpful for analyzing low-memory and OOM issues.
> 
> And break it up for memory used. Ring buffers, events, etc.
> 
> Perhaps even add one per CPU as well.
> 
> I'm always conscience about how much memory tracing is taking up in the
> system.
> 
> -- Steve