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Thanks, Steve.

For the initial implementation, I plan to add:

  /sys/kernel/tracing/trace_stats/total_memory_kb

The file would use an extensible key/value format. Initially it would<= /div>
report the ring-buffer data capacity:

  total:                &= nbsp;  395664
  ring_buffer:             395= 664
  ring_buffer_live:        395544
  ring_buffer_snapshot:       120

Here, ring_buffer is the sum of ring_buffer_live and
ring_buffer_snapshot. The values cover the global trace array and all<= /div>
tracing instances across all tracing CPUs.

Additional accounted categories, such as event memory, could be append= ed
later and included in total. Per-CPU statistics could be exposed
separately under trace_stats/per_cpu/cpuN/ to avoid mixing aggregate a= nd
per-CPU values in one file.

Userspace would parse fields by name and ignore unknown fields, so new=
categories can be added without changing the existing format.

Does this initial format look reasonable?

Thanks,
Xiang


=B7=A2=BC=FE=C8=CB: Steve= n Rostedt <rostedt@goodmis.org>
=B7=A2=CB=CD=CA=B1=BC=E4: 2026=C4=EA8=D4=C211=C8=D5 22:08:30
=CA=D5=BC=FE=C8=CB: Xiang Gao
=B3=AD=CB=CD: Masami Hiramatsu; Mathieu Desnoyers; Lorenzo Stoakes; = gao xu; =D3=A1=B4=B3; linux-trace-kernel@vger.kernel.org; linux-kernel@vger= .kernel.org; linux-mm@kvack.org; =B8=DF=CF=E8
=D6=F7=CC=E2: [External Mail]Re: [RFC] tracing: aggregate ring-buffe= r usage statistics
 
[=CD=E2=B2=BF=D3=CA=BC=FE] =B4=CB=D3=CA=BC=FE=C0= =B4=D4=B4=D3=DA=D0=A1=C3=D7=B9=AB=CB=BE=CD=E2=B2=BF=A3=AC=C7=EB=BD=F7=C9=F7= =B4=A6=C0=ED=A1=A3=C8=F4=B6=D4=D3=CA=BC=FE=B0=B2=C8=AB=D0=D4=B4=E6=D2=C9=A3= =AC=C7=EB=BD=AB=D3=CA=BC=FE=D7=AA=B7=A2=B8=F8misec@xiaomi.com=BD=F8=D0=D0= =B7=B4=C0=A1

On Tue, 11 Aug 2026 19:48:18 +0800
Xiang Gao <gxxa03070307@gmail.com> wrote:

> One possible interface would be under:
>
>   /sys/kernel/tracing/trace_stats/
>
> It could provide an aggregate buffer value together with a breakdown > for main and snapshot buffers. Per-CPU statistics could also be added<= br> > if useful.

As I previous said. I'm OK with adding a file there.

-- Steve
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