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Date: Tue, 30 Sep 2008 10:23:21 -0700
From: "Martin Bligh" <mbligh@google.com>
To: "Steven Rostedt" <rostedt@goodmis.org>
Subject: Re: [RFC PATCH] LTTng relay buffer allocation, read, write
Cc: "Mathieu Desnoyers" <mathieu.desnoyers@polymtl.ca>,
       "Peter Zijlstra" <a.p.zijlstra@chello.nl>, linux-kernel@vger.kernel.org,
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On Tue, Sep 30, 2008 at 10:22 AM, Martin Bligh <mbligh@google.com> wrote:
>> A 4 byte dataless payload is useless anyway.
>
> Not at all convinced that's true - we used it for lots of things.
> Start and end of irq event is one frequent example.
>
> Also, in a compact mode, we can record start and end of
> syscalls like this (without parameters).

Ah, sorry, maybe I misread this. No data with no event ids, etc
is fairly useless. 4 bytes data including space to record event ids is OK.