<div dir="ltr">No, I get the same problem with or w/o setting the size<div class="gmail_extra"><br clear="all"><div><div class="gmail_signature">Anders Wallin</div></div>
<br><div class="gmail_quote">On Thu, Nov 13, 2014 at 5:45 PM, Julien Desfossez <span dir="ltr"><<a href="mailto:jdesfossez@efficios.com" target="_blank">jdesfossez@efficios.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Ok, so if you don't limit the size of the snapshot (remove the -m 1G) it<br>
works as expected ?<br>
<br>
Julien<br>
<span class=""><br>
On 14-11-13 10:33 AM, Anders Wallin wrote:<br>
> bug is introduced in 68808f4e0bbb3adccff72ff9dab6ec9f3a9e6866<br>
><br>
> Regards<br>
><br>
> Anders<br>
><br>
> Anders Wallin<br>
><br>
> On Thu, Nov 13, 2014 at 10:39 AM, Anders Wallin <<a href="mailto:wallinux@gmail.com">wallinux@gmail.com</a><br>
</span><span class="">> <mailto:<a href="mailto:wallinux@gmail.com">wallinux@gmail.com</a>>> wrote:<br>
><br>
><br>
><br>
> Anders Wallin<br>
><br>
> On Thu, Nov 13, 2014 at 8:43 AM, Anders Wallin <<a href="mailto:wallinux@gmail.com">wallinux@gmail.com</a><br>
</span><span class="">> <mailto:<a href="mailto:wallinux@gmail.com">wallinux@gmail.com</a>>> wrote:<br>
><br>
> On Thu, Nov 13, 2014 at 12:11 AM, Julien Desfossez<br>
</span><span class="">> <<a href="mailto:jdesfossez@efficios.com">jdesfossez@efficios.com</a> <mailto:<a href="mailto:jdesfossez@efficios.com">jdesfossez@efficios.com</a>>> wrote:<br>
><br>
> Hi,<br>
><br>
> On 14-11-12 05:30 PM, Jérémie Galarneau wrote:<br>
> > On Wed, Nov 12, 2014 at 7:39 AM, Anders Wallin<br>
</span><div><div class="h5">> <<a href="mailto:wallinux@gmail.com">wallinux@gmail.com</a> <mailto:<a href="mailto:wallinux@gmail.com">wallinux@gmail.com</a>>> wrote:<br>
> >> Hi,<br>
> >><br>
> >> using userspace snapshot mode in 2.5 seems to broken.<br>
> >><br>
> >> I have small stupid application(tracetest) generating<br>
> 1000 events<br>
> >><br>
> >> Running the script (the below is simplified version of<br>
> the script)<br>
> >><br>
> ----------------------------------------------------------------------------------<br>
> >> #!/bin/bash<br>
> >> LTTNG='lttng -n'<br>
> >> lttng-sessiond --no-kernel &<br>
> ><br>
> > You should use the "-d" flag to launch the sessiond as a<br>
> daemon. Using<br>
> > "&" might cause the "create" command to launch a second<br>
> session daemon<br>
> > since the first one would not have had the time to open<br>
> create its<br>
> > command sockets.<br>
> ><br>
> >><br>
> >> $LTTNG create test --snapshot<br>
> >> $LTTNG enable-channel -u --subbuf-size 64k --num-subbuf<br>
> 16 --overwrite ch1<br>
> >> $LTTNG enable-event -u -c ch1 "*"<br>
> >> $LTTNG start<br>
> >> $LTTNG list ch1<br>
> >><br>
> >> mkdir -p snapshot/<br>
> >><br>
> >> for i in $(seq 1 $LOOPS); do<br>
> >> ./tracetest<br>
> >> $LTTNG snapshot record -m 1G<br>
> >><br>
> >> # print no of events and first and last event<br>
> >> last=$(ls -1drt $HOME/lttng-traces/$SESSION*/* | tail -1)<br>
</div></div>> >> babeltrace $last > snapshot/$<a href="http://i.bt" target="_blank">i.bt</a> <<a href="http://i.bt" target="_blank">http://i.bt</a>><br>
> >> cat snapshot/$<a href="http://i.bt" target="_blank">i.bt</a> <<a href="http://i.bt" target="_blank">http://i.bt</a>> | wc -l<br>
> >> cat snapshot/$<a href="http://i.bt" target="_blank">i.bt</a> <<a href="http://i.bt" target="_blank">http://i.bt</a>> | head -1<br>
> >> cat snapshot/$<a href="http://i.bt" target="_blank">i.bt</a> <<a href="http://i.bt" target="_blank">http://i.bt</a>> | tail -1<br>
<div><div class="h5">> >> done<br>
> >><br>
> >> $LTTNG stop<br>
> >> $LTTNG destroy $SESSION<br>
> >><br>
> ----------------------------------------------------------------------------------<br>
> >><br>
> >> The result of the run looks like this;<br>
> >> ./test.run<br>
> >> Error: consumer err socket second poll error<br>
> >> Error: Health error occurred in thread_manage_consumer<br>
> >> PERROR - 13:36:59.685167 [23772/23781]: bind inet:<br>
> Address already in use<br>
> >> (in lttcomm_bind_inet_sock() at inet.c:109)<br>
> >> Warning: Another session daemon is using this JUL port.<br>
> JUL support will be<br>
> >> deactivated to prevent interfering with the tracing.<br>
> >><br>
> ><br>
> > Is there a reason why you run two session daemons? I'm<br>
> guessing this<br>
> > is related to my "& vs -d" comment above.<br>
> ><br>
> >> lttng (LTTng Trace Control) 2.5.2 - Fumisterie<br>
> >> BabelTrace Trace Viewer and Converter 1.2.4<br>
> >> linux-vdso.so.1 => (0x00007fffba966000)<br>
> >> liblttng-ctl.so.0 =><br>
> /usr/lib/x86_64-linux-gnu/liblttng-ctl.so.0<br>
> >> (0x00007fbfe4b1d000)<br>
> >> librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1<br>
> (0x00007fbfe4915000)<br>
> >> libxml2.so.2 =><br>
> /usr/lib/x86_64-linux-gnu/libxml2.so.2<br>
> >> (0x00007fbfe45ae000)<br>
> >> libpopt.so.0 => /lib/x86_64-linux-gnu/libpopt.so.0<br>
> >> (0x00007fbfe43a2000)<br>
> >> libpthread.so.0 =><br>
> /lib/x86_64-linux-gnu/libpthread.so.0<br>
> >> (0x00007fbfe4184000)<br>
> >> libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6<br>
> (0x00007fbfe3dbd000)<br>
> >> /lib64/ld-linux-x86-64.so.2 (0x00007fbfe4fac000)<br>
> >> liburcu.so.2 =><br>
> /usr/lib/x86_64-linux-gnu/liburcu.so.2<br>
> >> (0x00007fbfe3bb6000)<br>
> >> libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2<br>
> (0x00007fbfe39b2000)<br>
> >> libz.so.1 => /lib/x86_64-linux-gnu/libz.so.1<br>
> (0x00007fbfe3798000)<br>
> >> liblzma.so.5 => /lib/x86_64-linux-gnu/liblzma.so.5<br>
> >> (0x00007fbfe3576000)<br>
> >> libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6<br>
> (0x00007fbfe3270000)<br>
> >><br>
> >> Session test created.<br>
> >> Default snapshot output set to:<br>
> >> /home/awallin/lttng-traces/test-20141112-133700<br>
> >> Snapshot mode set. Every channel enabled for that session<br>
> will be set in<br>
> >> overwrite mode and mmap output.<br>
> >> UST channel ch1 enabled for session test<br>
> >> UST event * created in channel ch1<br>
> >> Tracing started for session test<br>
> >> Tracing session test: [active snapshot]<br>
> >> Trace path:<br>
> >> Live timer interval (usec): 4294967295<br>
> >><br>
> >> === Domain: UST global ===<br>
> >><br>
> >> Channels:<br>
> >> -------------<br>
> >> - ch1: [enabled]<br>
> >><br>
> >> Attributes:<br>
> >> overwrite mode: 1<br>
> >> subbufers size: 4096<br>
> >> number of subbufers: 16<br>
> >> switch timer interval: 0<br>
> >> read timer interval: 0<br>
> >> trace file count: 0<br>
> >> trace file size (bytes): 0<br>
> >> output: mmap()<br>
> >><br>
> >> Events:<br>
> >> * (type: tracepoint) [enabled]<br>
> >><br>
> >> Snapshot recorded successfully for session test<br>
> >> 84<br>
> >> [13:37:00.852615950] (+?.?????????) arn-awallin-mint-l3<br>
> >> ust_baddr_statedump:soinfo: { cpu_id = 4 }, { baddr =<br>
> 0x7FFFC6BC7000, sopath<br>
> >> = "[vdso]", size = 0, mtime = -1 }<br>
> >> [13:37:00.853798949] (+0.000000805) arn-awallin-mint-l3<br>
> tracetest:first_tp:<br>
> >> { cpu_id = 6 }, { my_string_field = "test",<br>
> my_integer_field = 999 }<br>
> >> Snapshot recorded successfully for session test<br>
> >> 157<br>
> >> [13:37:00.853735195] (+?.?????????) arn-awallin-mint-l3<br>
> tracetest:first_tp:<br>
> >> { cpu_id = 6 }, { my_string_field = "test",<br>
> my_integer_field = 927 }<br>
> >> [13:37:00.894839116] (+0.000000299) arn-awallin-mint-l3<br>
> tracetest:first_tp:<br>
> >> { cpu_id = 5 }, { my_string_field = "test",<br>
> my_integer_field = 999 }<br>
> >> Snapshot recorded successfully for session test<br>
> >> 168<br>
> >> [13:37:00.853735195] (+?.?????????) arn-awallin-mint-l3<br>
> tracetest:first_tp:<br>
> >> { cpu_id = 6 }, { my_string_field = "test",<br>
> my_integer_field = 927 }<br>
> >> [13:37:00.929447330] (+0.000000305) arn-awallin-mint-l3<br>
> tracetest:first_tp:<br>
> >> { cpu_id = 5 }, { my_string_field = "test",<br>
> my_integer_field = 999 }<br>
> >> Snapshot recorded successfully for session test<br>
><br>
> Something is wrong from here:<br>
> >> 168<br>
> >> [13:37:00.894411117] (+?.?????????) arn-awallin-mint-l3<br>
> >> ust_baddr_statedump:soinfo: { cpu_id = 4 }, { baddr = 0x7FFF6BF81000, sopath<br>
> >> = "[vdso]", size = 0, mtime = -1 }<br>
> >> [13:37:00.972035546] (+0.000000597) arn-awallin-mint-l3 tracetest:first_tp:<br>
> >> { cpu_id = 6 }, { my_string_field = "test", my_integer_field = 999 }<br>
> >> Snapshot recorded successfully for session test<br>
> >> 168<br>
> >> [13:37:00.894411117] (+?.?????????) arn-awallin-mint-l3<br>
> >> ust_baddr_statedump:soinfo: { cpu_id = 4 }, { baddr = 0x7FFF6BF81000, sopath<br>
> >> = "[vdso]", size = 0, mtime = -1 }<br>
</div></div>> >> [13:37:01.<a href="tel:014060940" value="+4614060940">014060940</a> <tel:<a href="tel:014060940" value="+4614060940">014060940</a>>] (+0.000000341)<br>
<span class="">> arn-awallin-mint-l3 tracetest:first_tp:<br>
> >> { cpu_id = 7 }, { my_string_field = "test", my_integer_field = 999 }<br>
> >> Snapshot recorded successfully for session test<br>
> >> 168<br>
> >> [13:37:00.894411117] (+?.?????????) arn-awallin-mint-l3<br>
> >> ust_baddr_statedump:soinfo: { cpu_id = 4 }, { baddr = 0x7FFF6BF81000, sopath<br>
> >> = "[vdso]", size = 0, mtime = -1 }<br>
</span>> >> [13:37:01.<a href="tel:052555877" value="+4652555877">052555877</a> <tel:<a href="tel:052555877" value="+4652555877">052555877</a>>] (+0.000000872)<br>
<span class="">> arn-awallin-mint-l3 tracetest:first_tp:<br>
> >> { cpu_id = 6 }, { my_string_field = "test", my_integer_field = 999 }<br>
> ... to here.<br>
><br>
> The beginning timestamp is the same, the number of events is<br>
> the same,<br>
> but the end timestamp moves. We see also this pattern below.<br>
> I would be really interested to see the whole snapshots when<br>
> it happens.<br>
> It seems like we are not be overwriting the beginning of the<br>
> ring buffer<br>
> in some conditions. Could you send us your tracetest program<br>
> and the<br>
> script so we can try to reproduce the problem ?<br>
><br>
><br>
> I will append it including a run with debug turned on and all<br>
> the snapshot files created<br>
><br>
><br>
><br>
> >> Snapshot recorded successfully for session test<br>
> >> 168<br>
</span>> >> [13:37:01.<a href="tel:014035993" value="+4614035993">014035993</a> <tel:<a href="tel:014035993" value="+4614035993">014035993</a>>] (+?.?????????)<br>
<span class="">> arn-awallin-mint-l3 tracetest:first_tp:<br>
> >> { cpu_id = 7 }, { my_string_field = "test",<br>
> my_integer_field = 927 }<br>
> >> [13:37:01.098620808] (+0.000001404) arn-awallin-mint-l3<br>
> tracetest:first_tp:<br>
> >> { cpu_id = 4 }, { my_string_field = "test",<br>
> my_integer_field = 999 }<br>
> >> Snapshot recorded successfully for session test<br>
> >> 168<br>
</span>> >> [13:37:01.<a href="tel:097087388" value="+4697087388">097087388</a> <tel:<a href="tel:097087388" value="+4697087388">097087388</a>>] (+?.?????????)<br>
<span class="">> arn-awallin-mint-l3<br>
> >> ust_baddr_statedump:soinfo: { cpu_id = 6 }, { baddr =<br>
> 0x7FFF4BFFE000, sopath<br>
> >> = "[vdso]", size = 0, mtime = -1 }<br>
> >> [13:37:01.129839830] (+0.000000533) arn-awallin-mint-l3<br>
> tracetest:first_tp:<br>
> >> { cpu_id = 7 }, { my_string_field = "test",<br>
> my_integer_field = 999 }<br>
> >> Snapshot recorded successfully for session test<br>
> >> 168<br>
</span>> >> [13:37:01.<a href="tel:097087388" value="+4697087388">097087388</a> <tel:<a href="tel:097087388" value="+4697087388">097087388</a>>] (+?.?????????)<br>
<span class="">> arn-awallin-mint-l3<br>
> >> ust_baddr_statedump:soinfo: { cpu_id = 6 }, { baddr =<br>
> 0x7FFF4BFFE000, sopath<br>
> >> = "[vdso]", size = 0, mtime = -1 }<br>
> >> [13:37:01.129839830] (+0.000000533) arn-awallin-mint-l3<br>
> tracetest:first_tp:<br>
> >> { cpu_id = 7 }, { my_string_field = "test",<br>
> my_integer_field = 999 }<br>
> >> Snapshot recorded successfully for session test<br>
> >> 168<br>
</span>> >> [13:37:01.<a href="tel:097087388" value="+4697087388">097087388</a> <tel:<a href="tel:097087388" value="+4697087388">097087388</a>>] (+?.?????????)<br>
<div><div class="h5">> arn-awallin-mint-l3<br>
> >> ust_baddr_statedump:soinfo: { cpu_id = 6 }, { baddr =<br>
> 0x7FFF4BFFE000, sopath<br>
> >> = "[vdso]", size = 0, mtime = -1 }<br>
> >> [13:37:01.172829105] (+0.000000575) arn-awallin-mint-l3<br>
> tracetest:first_tp:<br>
> >> { cpu_id = 5 }, { my_string_field = "test",<br>
> my_integer_field = 999 }<br>
> >> Snapshot recorded successfully for session test<br>
> >> 168<br>
> >> [13:37:01.172021557] (+?.?????????) arn-awallin-mint-l3<br>
> >> ust_baddr_statedump:soinfo: { cpu_id = 7 }, { baddr =<br>
> 0x7FFF653FE000, sopath<br>
> >> = "[vdso]", size = 0, mtime = -1 }<br>
> >> [13:37:01.220074165] (+0.000000553) arn-awallin-mint-l3<br>
> tracetest:first_tp:<br>
> >> { cpu_id = 6 }, { my_string_field = "test",<br>
> my_integer_field = 999 }<br>
> >> Waiting for data availability<br>
> >> Tracing stopped for session test<br>
> >> Session test destroyed<br>
> >><br>
> >> the result from the run on older versions of lttng<br>
> creates bigger and bigger<br>
> >> event traces until reaching max size.<br>
> We see this pattern here and the max size seems to be 168<br>
> events, was it<br>
> similar in your previous tests ?<br>
><br>
> If I'm running the same test on 2.4 or 2.3 the max number of<br>
> events is much bigger, like ~10000<br>
> (I don't have the exact number right now, I will rebuild and run<br>
> the test again and get back<br>
> with traces from that run)<br>
><br>
> For 2.4.2 the log looks like this:<br>
> ./test.run ./tracetest<br>
><br>
> lttng (LTTng Trace Control) 2.4.2 - Époque Opaque<br>
> BabelTrace Trace Viewer and Converter 1.2.1<br>
> linux-vdso.so.1 => (0x00007fff775fe000)<br>
> liblttng-ctl.so.0 => /usr/local/lib/liblttng-ctl.so.0<br>
> (0x00002b2b016e4000)<br>
> libpopt.so.0 => /lib/x86_64-linux-gnu/libpopt.so.0 (0x00002b2b0190f000)<br>
> libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0<br>
> (0x00002b2b01b1b000)<br>
> libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00002b2b01d39000)<br>
> librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1 (0x00002b2b020ff000)<br>
> liburcu.so.3 => /usr/local/lib/liburcu.so.3 (0x00002b2b02307000)<br>
> /lib64/ld-linux-x86-64.so.2 (0x00002b2b014bf000)<br>
><br>
> Session test created.<br>
> Default snapshot output set to: //lttng-traces/test-20141113-093611<br>
> Snapshot mode set. Every channel enabled for that session will be<br>
> set in overwrite mode and mmap output.<br>
> UST channel ch1 enabled for session test<br>
> UST event * created in channel ch1<br>
> Tracing started for session test<br>
> Tracing session test: [active snapshot]<br>
> Trace path:<br>
><br>
> === Domain: UST global ===<br>
><br>
> Buffer type: per UID<br>
><br>
> Channels:<br>
> -------------<br>
> - ch1: [enabled]<br>
><br>
> Attributes:<br>
> overwrite mode: 1<br>
> subbufers size: 4096<br>
> number of subbufers: 16<br>
> switch timer interval: 0<br>
> read timer interval: 0<br>
> output: mmap()<br>
><br>
> Events:<br>
> * (type: tracepoint) [enabled]<br>
><br>
> Snapshot recorded successfully for session test<br>
> 1000<br>
> [09:36:11.985319272] (+?.?????????) 07f8cf84a38f tracetest:first_tp:<br>
> { cpu_id = 4 }, { my_string_field = "test", my_integer_field = 0 }<br>
> [09:36:11.985857254] (+0.000000501) 07f8cf84a38f tracetest:first_tp:<br>
> { cpu_id = 4 }, { my_string_field = "test", my_integer_field = 999 }<br>
> Snapshot recorded successfully for session test<br>
> 2000<br>
> [09:36:11.985319272] (+?.?????????) 07f8cf84a38f tracetest:first_tp:<br>
> { cpu_id = 4 }, { my_string_field = "test", my_integer_field = 0 }<br>
</div></div>> [09:36:12.033066130 <tel:033066130>] (+0.000001663) 07f8cf84a38f<br>
<span class="">> tracetest:first_tp: { cpu_id = 5 }, { my_string_field = "test",<br>
> my_integer_field = 999 }<br>
> Snapshot recorded successfully for session test<br>
> 3000<br>
> [09:36:11.985319272] (+?.?????????) 07f8cf84a38f tracetest:first_tp:<br>
> { cpu_id = 4 }, { my_string_field = "test", my_integer_field = 0 }<br>
</span>> [09:36:12.086888121 <tel:086888121>] (+0.000001273) 07f8cf84a38f<br>
<div class="HOEnZb"><div class="h5">> tracetest:first_tp: { cpu_id = 5 }, { my_string_field = "test",<br>
> my_integer_field = 999 }<br>
> Snapshot recorded successfully for session test<br>
> 4000<br>
> [09:36:11.985319272] (+?.?????????) 07f8cf84a38f tracetest:first_tp:<br>
> { cpu_id = 4 }, { my_string_field = "test", my_integer_field = 0 }<br>
> [09:36:12.147378251] (+0.000001257) 07f8cf84a38f tracetest:first_tp:<br>
> { cpu_id = 4 }, { my_string_field = "test", my_integer_field = 999 }<br>
> Snapshot recorded successfully for session test<br>
> 5000<br>
> [09:36:11.985319272] (+?.?????????) 07f8cf84a38f tracetest:first_tp:<br>
> { cpu_id = 4 }, { my_string_field = "test", my_integer_field = 0 }<br>
> [09:36:12.225584696] (+0.000000528) 07f8cf84a38f tracetest:first_tp:<br>
> { cpu_id = 4 }, { my_string_field = "test", my_integer_field = 999 }<br>
> Snapshot recorded successfully for session test<br>
> 6000<br>
> [09:36:11.985319272] (+?.?????????) 07f8cf84a38f tracetest:first_tp:<br>
> { cpu_id = 4 }, { my_string_field = "test", my_integer_field = 0 }<br>
> [09:36:12.288311172] (+0.000000571) 07f8cf84a38f tracetest:first_tp:<br>
> { cpu_id = 7 }, { my_string_field = "test", my_integer_field = 999 }<br>
> Snapshot recorded successfully for session test<br>
> 7000<br>
> [09:36:11.985319272] (+?.?????????) 07f8cf84a38f tracetest:first_tp:<br>
> { cpu_id = 4 }, { my_string_field = "test", my_integer_field = 0 }<br>
> [09:36:12.375789307] (+0.000001238) 07f8cf84a38f tracetest:first_tp:<br>
> { cpu_id = 4 }, { my_string_field = "test", my_integer_field = 999 }<br>
> Snapshot recorded successfully for session test<br>
> 7000<br>
> [09:36:12.032314084] (+?.?????????) 07f8cf84a38f tracetest:first_tp:<br>
> { cpu_id = 5 }, { my_string_field = "test", my_integer_field = 0 }<br>
> [09:36:12.460756779] (+0.000001248) 07f8cf84a38f tracetest:first_tp:<br>
> { cpu_id = 4 }, { my_string_field = "test", my_integer_field = 999 }<br>
> Snapshot recorded successfully for session test<br>
> 8000<br>
> [09:36:12.032314084] (+?.?????????) 07f8cf84a38f tracetest:first_tp:<br>
> { cpu_id = 5 }, { my_string_field = "test", my_integer_field = 0 }<br>
> [09:36:12.540464090] (+0.000001292) 07f8cf84a38f tracetest:first_tp:<br>
> { cpu_id = 7 }, { my_string_field = "test", my_integer_field = 999 }<br>
> Snapshot recorded successfully for session test<br>
> 9000<br>
> [09:36:12.032314084] (+?.?????????) 07f8cf84a38f tracetest:first_tp:<br>
> { cpu_id = 5 }, { my_string_field = "test", my_integer_field = 0 }<br>
> [09:36:12.621992931] (+0.000001298) 07f8cf84a38f tracetest:first_tp:<br>
> { cpu_id = 5 }, { my_string_field = "test", my_integer_field = 999 }<br>
> Waiting for data availability<br>
> Tracing stopped for session test<br>
> Session test destroyed<br>
><br>
><br>
><br>
> ><br>
> > Unless I'm mistaken, the behavior of the snapshot mode has changed<br>
> > between 2.4 and 2.5.<br>
> ><br>
> > In the 2.4 series, consecutive snapshots could overlap; that is,<br>
> > events could be present in multiple snapshots. As of 2.5, an event is<br>
> > guaranteed to only appear in one snapshot as the events are considered<br>
> > as having been "consumed" at that point.<br>
><br>
> Hum, no the behavior is still the same, consecutive<br>
> snapshots can overlap.<br>
><br>
> Could you tell us on which architecture you are experiencing<br>
> the problem<br>
> and the number of CPUs ?<br>
><br>
> The traces appended is from my laptop running Ubuntu 14.04 with<br>
> "8" cpu's<br>
> model name : Intel(R) Core(TM) i7-2760QM CPU @ 2.40GHz<br>
> I have also run this on ARM with 16 cores and a powerpc<br>
><br>
><br>
> Thanks,<br>
><br>
> Julien<br>
><br>
><br>
><br>
><br>
</div></div></blockquote></div><br></div></div>