From: Steven Rostedt <rostedt@goodmis.org>
To: Daniel Bristot de Oliveira <bristot@redhat.com>
Cc: linux-kernel@vger.kernel.org, Phil Auld <pauld@redhat.com>,
Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
Kate Carcia <kcarcia@redhat.com>,
Jonathan Corbet <corbet@lwn.net>, Ingo Molnar <mingo@redhat.com>,
Peter Zijlstra <peterz@infradead.org>,
Thomas Gleixner <tglx@linutronix.de>,
Alexandre Chartre <alexandre.chartre@oracle.com>,
Clark Willaims <williams@redhat.com>,
John Kacur <jkacur@redhat.com>,
Juri Lelli <juri.lelli@redhat.com>,
linux-doc@vger.kernel.org
Subject: Re: [PATCH V3 9/9] tracing: Add timerlat tracer
Date: Sat, 12 Jun 2021 19:06:41 -0400 [thread overview]
Message-ID: <20210612190641.4dc6dce0@rorschach.local.home> (raw)
In-Reply-To: <6808245d-208c-c6d2-1c6e-7410df158992@redhat.com>
On Sat, 12 Jun 2021 11:41:41 +0200
Daniel Bristot de Oliveira <bristot@redhat.com> wrote:
> > I think the above may be easier to understand, especially if the trace
> > output that represents it is below.
>
> ok, I can try to capture a trace sample and represent it into the ASCII art
> format above.
Why capture it? Just fudge an example that fits the example ;-)
>
> > Also, I have to ask, shouldn't the "thread noise" really start at the
> > "External clock event"?
>
> To go in that direction, we need to track things that delayed the IRQ execution.
[snip long explanation of the obvious (to me at least) ;-) ]
> the overhead is acceptable because of the sound analysis of the scheduling bound
> (which is rooted in a formal specification & analysis of the system).
I meant, that it needs to be documented, what the real thread noise is
but due to what is available it may not be truly accurate.
-- Steve
next prev parent reply other threads:[~2021-06-12 23:06 UTC|newest]
Thread overview: 57+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-14 20:51 [PATCH V3 0/9] hwlat improvements and osnoise/timerlat tracers Daniel Bristot de Oliveira
2021-05-14 20:51 ` [PATCH V3 1/9] tracing/hwlat: Fix Clark's email Daniel Bristot de Oliveira
2021-05-14 20:51 ` [PATCH V3 2/9] tracing/hwlat: Implement the mode config option Daniel Bristot de Oliveira
2021-06-03 20:11 ` Steven Rostedt
2021-05-14 20:51 ` [PATCH V3 3/9] tracing/hwlat: Switch disable_migrate to mode none Daniel Bristot de Oliveira
2021-05-14 20:51 ` [PATCH V3 4/9] tracing/hwlat: Implement the per-cpu mode Daniel Bristot de Oliveira
2021-05-27 11:58 ` Juri Lelli
2021-05-27 12:29 ` Daniel Bristot de Oliveira
2021-06-03 21:17 ` Steven Rostedt
2021-06-04 15:31 ` Daniel Bristot de Oliveira
2021-05-14 20:51 ` [PATCH V3 5/9] tracing/trace: Add a generic function to read/write u64 values from tracefs Daniel Bristot de Oliveira
2021-06-03 21:22 ` Steven Rostedt
2021-06-04 16:05 ` Daniel Bristot de Oliveira
2021-06-04 16:18 ` Steven Rostedt
2021-06-04 16:34 ` Daniel Bristot de Oliveira
2021-05-14 20:51 ` [PATCH V3 6/9] trace/hwlat: Use the generic function to read/write width and window Daniel Bristot de Oliveira
2021-06-03 21:27 ` Steven Rostedt
2021-06-04 16:36 ` Daniel Bristot de Oliveira
2021-06-04 20:50 ` Steven Rostedt
2021-05-14 20:51 ` [PATCH V3 7/9] tracing: Add __print_ns_to_secs() and __print_ns_without_secs() helpers Daniel Bristot de Oliveira
2021-06-03 21:29 ` Steven Rostedt
2021-06-04 4:19 ` Joe Perches
2021-06-04 16:21 ` Steven Rostedt
2021-06-04 19:09 ` [PATCH] treewide: Add missing semicolons to __assign_str uses Joe Perches
2021-06-04 19:38 ` Joe Perches
2021-06-07 23:18 ` Jason Gunthorpe
2021-06-12 15:42 ` [PATCH V2] " Joe Perches
2021-06-12 23:11 ` Steven Rostedt
2021-06-30 11:28 ` Joe Perches
2021-06-30 12:22 ` Steven Rostedt
2021-06-04 16:07 ` [PATCH V3 7/9] tracing: Add __print_ns_to_secs() and __print_ns_without_secs() helpers Daniel Bristot de Oliveira
2021-05-14 20:51 ` [PATCH V3 8/9] tracing: Add osnoise tracer Daniel Bristot de Oliveira
2021-06-03 21:31 ` Steven Rostedt
2021-06-04 21:28 ` Steven Rostedt
2021-06-07 12:00 ` Daniel Bristot de Oliveira
2021-06-07 15:47 ` Steven Rostedt
2021-06-08 15:24 ` Daniel Bristot de Oliveira
2021-06-08 17:17 ` Daniel Bristot de Oliveira
2021-06-08 17:39 ` Steven Rostedt
2021-06-08 19:33 ` Daniel Bristot de Oliveira
2021-06-08 19:42 ` Steven Rostedt
2021-06-09 12:14 ` Daniel Bristot de Oliveira
2021-06-09 13:03 ` Steven Rostedt
2021-06-09 13:44 ` Daniel Bristot de Oliveira
2021-05-14 20:51 ` [PATCH V3 9/9] tracing: Add timerlat tracer Daniel Bristot de Oliveira
2021-06-08 1:36 ` Steven Rostedt
2021-06-11 12:59 ` Daniel Bristot de Oliveira
2021-06-11 20:03 ` Steven Rostedt
2021-06-12 9:41 ` Daniel Bristot de Oliveira
2021-06-12 23:06 ` Steven Rostedt [this message]
2021-06-11 14:13 ` Daniel Bristot de Oliveira
2021-06-11 20:48 ` Steven Rostedt
2021-06-12 8:47 ` Daniel Bristot de Oliveira
2021-06-12 23:09 ` Steven Rostedt
2021-06-15 8:18 ` Daniel Bristot de Oliveira
2021-05-27 12:07 ` [PATCH V3 0/9] hwlat improvements and osnoise/timerlat tracers Juri Lelli
2021-05-29 2:16 ` Steven Rostedt
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