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Re: Unified tracing buffer
- From: "Martin Bligh" <mbligh at google dot com>
- To: "KOSAKI Motohiro" <kosaki dot motohiro at jp dot fujitsu dot com>
- Cc: "Masami Hiramatsu" <mhiramat at redhat dot com>, "Linux Kernel Mailing List" <linux-kernel at vger dot kernel dot org>, "Linus Torvalds" <torvalds at linux-foundation dot org>, "Thomas Gleixner" <tglx at linutronix dot de>, "Mathieu Desnoyers" <compudj at krystal dot dyndns dot org>, "Steven Rostedt" <rostedt at goodmis dot org>, od at novell dot com, "Frank Ch. Eigler" <fche at redhat dot com>, systemtap-ml <systemtap at sources dot redhat dot com>
- Date: Tue, 23 Sep 2008 11:28:17 -0700
- Subject: Re: Unified tracing buffer
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- References: <20080923232239.DC1E.KOSAKI.MOTOHIRO@jp.fujitsu.com> <48D90970.3060409@redhat.com> <20080924025457.DC24.KOSAKI.MOTOHIRO@jp.fujitsu.com>
>> I think the main reason of using single-channel mode is simplicity of
>> userspace reader. We can use 'cat' or 'tail' to read the buffer on-line.
>> I'm not sure how much overhead ftrace-like buffer merging routine has,
>> but if kernel provides an interface which gives us single-merged buffer
>> image(like ftrace buffer), we are grad to use it. :-)
>
> Yup, I also think it is better.
That was the plan, yes. Merge sort is cheap ;-)