Thanks for point that out. But My point is creating session would fail as root, only after I failed enable kernel event as normal user.<br><br>
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<blockquote style="BORDER-LEFT:#ccc 1px solid;MARGIN:0px 0px 0px 0.8ex;PADDING-LEFT:1ex" class="gmail_quote">On Wed, Mar 19, 2014 at 1:11 AM, Jonathan Rajotte <span dir="ltr"><<a href="mailto:jonathan.r.julien@gmail.com" target="_blank">jonathan.r.julien@gmail.com</a>></span> wrote:<br>
<blockquote style="BORDER-LEFT:#ccc 1px solid;MARGIN:0px 0px 0px 0.8ex;PADDING-LEFT:1ex" class="gmail_quote">
<div dir="ltr">AFAIK if you want to use kernel tracing as a regular user you need:
<div>1) to be part of a tracing user group (default: tracing [1])</div>
<div>2) sessiond must be started by root</div>
<div><br></div>
<div>you can use "sudo lttng-sessiond -d" before doing any lttng related tasks and/or you can add sessiond to your boot sequence. </div>
<div><br></div>
<div>[1] you might need to create it, you can also use another group via lttng-sessiond -g <group_name></div></div>
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<div class="gmail_extra"><br><br></div></div></div></blockquote></blockquote>On Tue, Mar 18, 2014 at 12:53 PM, Lingyu Zhu <span dir="ltr"><<a href="mailto:lynuszhu@gmail.com" target="_blank">lynuszhu@gmail.com</a>></span> wrote:<br>
<blockquote style="BORDER-LEFT:#ccc 1px solid;MARGIN:0px 0px 0px 0.8ex;PADDING-LEFT:1ex" class="gmail_quote">
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<blockquote style="BORDER-LEFT:#ccc 1px solid;MARGIN:0px 0px 0px 0.8ex;PADDING-LEFT:1ex" class="gmail_quote"><br><br>
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<div>On Wed, Mar 19, 2014 at 12:35 AM, Jonathan Rajotte <span dir="ltr"><<a href="mailto:jonathan.r.julien@gmail.com" target="_blank">jonathan.r.julien@gmail.com</a>></span> wrote:<br></div>
<blockquote style="BORDER-LEFT:#ccc 1px solid;MARGIN:0px 0px 0px 0.8ex;PADDING-LEFT:1ex" class="gmail_quote">
<div dir="ltr">Hi Lingyu,
<div><br></div>
<div>
<div>
<blockquote style="BORDER-LEFT:#ccc 1px solid;MARGIN:0px 0px 0px 0.8ex;PADDING-LEFT:1ex" class="gmail_quote">
<div>Does a sessiond is created on boot ? </div>
<div>You can check via htop and filter for lttng or sessiond.</div></blockquote></div>No sessiond is created on boot before I do these operations.<br>what else info should I provide? </div>
<div><br></div></div>
<div>
<div>
<div class="gmail_extra"><br><br>
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<div>On Tue, Mar 18, 2014 at 12:31 PM, Lingyu Zhu <span dir="ltr"><<a href="mailto:lynuszhu@gmail.com" target="_blank">lynuszhu@gmail.com</a>></span> wrote:<br></div></div>
<blockquote style="BORDER-LEFT:#ccc 1px solid;MARGIN:0px 0px 0px 0.8ex;PADDING-LEFT:1ex" class="gmail_quote">
<div>
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<div dir="ltr">
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<div><span style="FONT-FAMILY:arial,sans-serif;FONT-SIZE:13px">Hello,</span>
<div style="FONT-FAMILY:arial,sans-serif;FONT-SIZE:13px">Sorry for being away a few days. My thesis opening proposal is hiting the deadline, which happens to be same date for GSoC. Now I can be fully devoted to lttng and compose my GSoC proposal.</div>
<div style="FONT-FAMILY:arial,sans-serif;FONT-SIZE:13px"><br></div>
<div style="FONT-FAMILY:arial,sans-serif;FONT-SIZE:13px">Anyway, I may have found a bug.I'm not very sure. Here is my log:</div>
<div style="FONT-FAMILY:arial,sans-serif;FONT-SIZE:13px"><br></div>
<div style="FONT-FAMILY:arial,sans-serif;FONT-SIZE:13px">===================================================</div>
<div style="FONT-FAMILY:arial,sans-serif;FONT-SIZE:13px">
<div>[lynus@slave1 ~]$lttng create</div>
<div>Spawning a session daemon</div>
<div>Session auto-20140319-081547 created.</div>
<div>Traces will be written in /home/lynus/lttng-traces/auto-20140319-081547</div>
<div>[lynus@slave1 ~]$ lttng enable-event page_block -k</div>
<div>Error: Event page_block: Tracing the kernel requires a root lttng-sessiond daemon, as well as "tracing" group membership or root user ID for the lttng client. (channel channel0, session auto-20140319-081547)</div>
<div>Warning: Some command(s) went wrong</div>
<div>[lynus@slave1 ~]$ lttng destroy</div>
<div>Session auto-20140319-081547 destroyed</div>
<div>[lynus@slave1 ~]$ sudo su -</div>
<div>[sudo] password for lynus: </div>
<div>root@slave1:~# lttng create</div>
<div>Spawning a session daemon</div>
<div>Warning: No tracing group detected</div>
<div>Session auto-20140319-081615 created.</div>
<div>Traces will be written in /root/lttng-traces/auto-20140319-081615</div>
<div>PERROR [4774/4882]: bind inet: Address already in use (in lttcomm_bind_inet_sock() at inet.c:109)</div>
<div>Warning: An other session daemon is using this JUL port. JUL support will be deactivated not interfering with the tracing.</div>
<div>root@slave1:~# lttng create</div>
<div>Session auto-20140319-081620 created.</div>
<div>Traces will be written in /root/lttng-traces/auto-20140319-081620</div>
<div>root@slave1:~# </div>
<div>[END] 2014/3/19 0:04:31</div></div>
<div style="FONT-FAMILY:arial,sans-serif;FONT-SIZE:13px">======================================================</div>
<div style="FONT-FAMILY:arial,sans-serif;FONT-SIZE:13px"><br></div></div></div>
<div style="FONT-FAMILY:arial,sans-serif;FONT-SIZE:13px">These command is issued right after my machine is booted. And it failed every time if I try to enable kernel event as non-root user first then switch to root to create session. If I directly switch to root and create a seesion, everything is normal. So I guess I may have come across a bug.</div>
<div style="FONT-FAMILY:arial,sans-serif;FONT-SIZE:13px">Any comment?</div></div><br></div></div>_______________________________________________<br>lttng-dev mailing list<br><a href="mailto:lttng-dev@lists.lttng.org" target="_blank">lttng-dev@lists.lttng.org</a><br>
<a href="http://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev" target="_blank">http://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev</a><br><br></blockquote></div><span><font color="#888888"><br><br clear="all">
<div><br></div>-- <br>
<div dir="ltr">Jonathan Rajotte Julien
<div>Chargé de laboratoire, INF1995<br>
<div>Polytechnique Montréal</div></div></div></font></span></div></div></div></blockquote></div><br></blockquote></div><br><br clear="all">
<div><br></div>-- <br>
<div dir="ltr">Jonathan Rajotte Julien
<div>Chargé de laboratoire, INF1995<br>
<div>Polytechnique Montréal</div></div></div></div></div></div></blockquote></div><br>