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Date: Tue, 6 Dec 2011 10:29:05 +0100
From: Robert Richter <robert.richter@amd.com>
To: Stephane Eranian <eranian@google.com>
CC: Frederic Weisbecker <fweisbec@gmail.com>,
        "acme@redhat.com" <acme@ghostprotocols.net>,
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Subject: Re: [PATCH] perf: make perf.data more self-descriptive (v8)
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On 05.12.11 11:24:05, Stephane Eranian wrote:
> The one thing I realized last week, is that all that header information, incl.
> the features bits do not seem to appear in the file perf.data file when you
> use the perf record pipe mode. We need to fix that otherwise, if you
> depend on information in those bits, it won't always be present. That's
> a major issue.

Yes, this is because pipes are not seakable, which is necessary to
write the features.

-Robert

-- 
Advanced Micro Devices, Inc.
Operating System Research Center