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<DIV
style="FONT-SIZE: small; FONT-FAMILY: 'Calibri'; FONT-WEIGHT: normal; COLOR: #000000; FONT-STYLE: normal; TEXT-DECORATION: none; DISPLAY: inline"><B>From:</B>
<A title=mathieu.desnoyers@efficios.com
href="mailto:mathieu.desnoyers@efficios.com">Mathieu Desnoyers</A> </DIV>
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<DIV><B>Sent:</B> Tuesday, November 05, 2013 3:20 PM</DIV>
<DIV><B>To:</B> <A title=david.lindstrom@percepio.se
href="mailto:david.lindstrom@percepio.se">DavidLindström</A> </DIV>
<DIV><B>Cc:</B> <A title=lttng-dev@lists.lttng.org
href="mailto:lttng-dev@lists.lttng.org">lttng-dev@lists.lttng.org</A> </DIV>
<DIV><B>Subject:</B> Re: [lttng-dev] Tagging traces with arbitrary data (as in
custommetadata)</DIV></DIV></DIV>
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style="FONT-SIZE: small; FONT-FAMILY: 'Calibri'; FONT-WEIGHT: normal; COLOR: #000000; FONT-STYLE: normal; TEXT-DECORATION: none; DISPLAY: inline">
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<BLOCKQUOTE
style="FONT-SIZE: 12pt; FONT-FAMILY: helvetica,arial,sans-serif; FONT-WEIGHT: normal; COLOR: #000; FONT-STYLE: normal; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; TEXT-DECORATION: none; BORDER-LEFT: #1010ff 2px solid"><B>From:
</B>"David Lindström" <david.lindstrom@percepio.se><BR><B>To:
</B>lttng-dev@lists.lttng.org<BR><B>Sent: </B>Tuesday, November 5, 2013
9:15:14 AM<BR><B>Subject: </B>[lttng-dev] Tagging traces with arbitrary data
(as in custom metadata)<BR>
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<DIV style="FONT-SIZE: 12pt; FONT-FAMILY: 'Calibri'; COLOR: #000000">
<DIV>Hi, I was wondering if there’s a way to tag a trace with some
additional information. A general example would be to include a description
of the current experiment. One way to do this currently would be to create a
custom lttng-message application with some UST tracepoint and then just log
that to a separate channel, but that would be pretty ugly. It would be much
cleaner to insert extra fields into the metadata stream. Is something like
that possible in current versions of LTTng and/or would it be possible to
add it for a future version?</DIV></DIV></DIV></BLOCKQUOTE>
<DIV> </DIV>
<DIV>The CTF metadata has an environment (env {}) section that contains this
kind of information. LTTng already uses it to store the tracer version and
some info about the system. We could eventually add a feature like this, a
"tag", that would be added to the CTF environment information. I would guess
that users would provide this tag on the lttng command line for their session,
and it would be passed to the tracers by sessiond.<BR></DIV>
<DIV> </DIV>
<DIV>Thoughts ?<BR></DIV>
<DIV><FONT face=Calibri></FONT> </DIV></DIV></DIV></BLOCKQUOTE>
<DIV dir=ltr>I have no idea how this would be implemented, I’m only looking at
potential uses. A simple tag field in the env{} section should cover my initial
use cases. I have to wonder though, how much more complicated it would be to
allow multiple named tags? For example, tags.description = ”Some description”
instead of tag = “Some description”?</DIV>
<DIV dir=ltr> </DIV>
<DIV dir=ltr>Also, how would one specify this? As an option to the lttng create
command or as a separate command (lttng set-tag ...)?</DIV>
<DIV dir=ltr> </DIV>
<DIV dir=ltr>Mvh</DIV>
<DIV dir=ltr>David Lindström</DIV>
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<DIV
style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif; COLOR: #000000">Thanks,<BR></DIV>
<DIV
style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif; COLOR: #000000"> </DIV>
<DIV
style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif; COLOR: #000000">Mathieu<BR></DIV>
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style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif; COLOR: #000000"> </DIV>
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style="FONT-SIZE: 12pt; FONT-FAMILY: helvetica,arial,sans-serif; FONT-WEIGHT: normal; COLOR: #000; FONT-STYLE: normal; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; TEXT-DECORATION: none; BORDER-LEFT: #1010ff 2px solid">
<DIV dir=ltr>
<DIV style="FONT-SIZE: 12pt; FONT-FAMILY: 'Calibri'; COLOR: #000000">
<DIV
style="FONT-SIZE: 12pt; FONT-FAMILY: 'Calibri'; COLOR: #000000">Mvh<BR>David
Lindström</DIV></DIV></DIV><BR>_______________________________________________<BR>lttng-dev
mailing
list<BR>lttng-dev@lists.lttng.org<BR>http://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev<BR></BLOCKQUOTE>
<DIV
style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif; COLOR: #000000"><BR><BR></DIV>
<DIV
style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif; COLOR: #000000"> </DIV>
<DIV
style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif; COLOR: #000000">--
<BR></DIV>
<DIV
style="FONT-SIZE: 12pt; FONT-FAMILY: times new roman, new york, times, serif; COLOR: #000000"><SPAN
name="x"></SPAN>Mathieu Desnoyers<BR>EfficiOS
Inc.<BR>http://www.efficios.com<SPAN
name="x"></SPAN><BR></DIV></BLOCKQUOTE></DIV></DIV>
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